Safety precautions during machining. Safety precautions when performing plumbing work
GOST 12.3.025-80
Group T58
INTERSTATE STANDARD
SYSTEM OF OCCUPATIONAL SAFETY STANDARDS
PROCESSING OF METALS BY CUTTING
Safety requirements
Occupational safety standards system.
Metal working by cutting. Safety requirements
Date of introduction 1982-07-01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the All-Union Central Council of Trade Unions
2. APPROVED AND ENTERED INTO EFFECT by Resolution of the USSR State Committee for Standards dated December 11, 1980 N 5771
3. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS
Item number |
|
GOST 3.1102-81 | |
GOST 3.1120-83 | |
GOST 9.085-78 | |
GOST 12.0.004-90 | |
GOST 12.1.004-91 | |
GOST 12.1.005-88 | 1.5, 3.6.1, 9.1 |
GOST 12.1.010-76 | |
GOST 12.1.012-90 | |
GOST 12.1.014-84 | |
GOST 12.1.016-79 | |
GOST 12.1.045-84 | |
GOST 12.1.050-86 | |
GOST 12.2.003-91 | |
GOST 12.2.009-99 | |
GOST 12.2.022-80 | |
GOST 12.2.029-88 | |
GOST 12.2.032-78 | |
GOST 12.2.033-78 | |
GOST 12.3.009-76 | |
GOST 12.3.010-82 | |
GOST 12.3.020-80 | |
GOST 12.3.028-82 | |
GOST 12.4.009-83 | |
GOST 12.4.011-89 | |
GOST 12.4.012-83 | |
GOST 12.4.026-76 | |
GOST 12.4.068-79 | |
GOST 12.4.124-83 | |
GOST 1510-84 | |
GOST 14861-86 | |
GOST 19822-88 | |
GOST 24940-81 | |
SN 3223-85 |
4. Tested in 1989
5. EDITION (March 2001) with Amendment No. 1, approved in March 1989 (ICS No. 6-89)
This standard establishes safety requirements for the development and implementation of processes for mechanical processing of metals by cutting (hereinafter referred to as cutting) on metal-cutting machines.
1. GENERAL PROVISIONS
1. GENERAL PROVISIONS
1.1. The development of technological documentation, organization and implementation of technological cutting processes must comply with the requirements of GOST 3.1102 and this standard.
1.2. Production equipment used for cutting must comply with the requirements of GOST 12.2.003 and GOST 12.2.009.
1.3. Devices for cutting must comply with the requirements of GOST 12.2.029.
1.4. Conveyors intended for interoperational movement of goods during cutting processing must comply with the requirements of GOST 12.2.022.
1.5. Maximum permissible concentrations of substances formed during cutting processing should not exceed the values established by GOST 12.1.005 and regulatory documents of the USSR Ministry of Health.
2. REQUIREMENTS FOR TECHNOLOGICAL PROCESSES
2.1. Safety requirements for cutting processes must be set out in technological documents (MK, CE, TI, VO, KTP, KTTP, OK, OKT, VOP, VTP AND VTO) according to GOST 3.1120.
Safety requirements must be met throughout the entire technological process, including technical control operations, movement (transportation), interoperational storage (warehousing) of processing facilities and removal of industrial waste.
2.2. The technological documentation for cutting processing must indicate the means of protection for workers.
2.3. Technological processes, including operations with the danger of explosion and fire, must be carried out in compliance with the requirements of GOST 12.1.010, GOST 12.1.004 and the “Standard Fire Safety Rules” approved by the Main Directorate for Fire Safety of the USSR Ministry of Internal Affairs.
2.4. Cutting processing of beryllium and its alloys must be carried out in accordance with SN N 993, approved by the USSR Ministry of Health.
2.5. Installation of workpieces to be processed and removal of finished parts during operation of the equipment is allowed outside the processing area, using special positioning devices (for example, rotary tables) that ensure the safety of workers.
2.6. When cutting workpieces that extend beyond the equipment, portable fences and safety signs must be installed in accordance with GOST 12.4.026.
2.7. To prevent the hands of machine operators from coming into contact with moving devices and tools when installing workpieces and removing parts, there must be automatic devices (mechanical arms, revolving devices, hoppers, etc.).
2.8. When grinding, titanium dust slurry should be removed while wet and dried in a specially designated area. Titanium waste in a finely divided state, coated with oil, must be degreased.
(Changed edition, Amendment No. 1).
2.9. Cutting of parts made of magnesium alloys should be carried out with a tool that eliminates the possibility of high friction and fire of the metal, without the use of cutting fluid (coolant).
If necessary, it is allowed to use mineral oil, free from acids and moisture.
2.10. Coolants used during cutting must comply with the requirements of the Sanitary Rules for working with cutting fluids and process lubricants, approved by the USSR Ministry of Health.
The basic range of coolants used in industry is given in reference Appendix 1.
Examples of the design of nozzles for supplying and spraying coolant are given in reference appendix 2.
2.11. When circulating in the cooling zone, coolant must be cleaned of mechanical impurities.
2.12. The coolant circulation system must have devices for dosed (for example, a pump) and directed supply of process fluids to the metal processing zone with automatic blocking of the coolant supply when the equipment stops operating.
2.13. Depending on the type of chips, the means for removing them should be selected in accordance with Table 1.
Table 1
Type of chips | Removal products |
Without coolant |
|
Fine crushed | Single screw conveyors |
Steel loach | Twin screw conveyors |
Loose | Vibrating conveyors |
Elemental | Pneumatic conveyor |
Any kind of shavings | Plate conveyor |
Using coolant |
|
Elemental cast iron | Scraper conveyors |
Elemental steel | Scraper and single screw conveyors |
Elemental and loach non-ferrous metals | Plate conveyors, hydraulic conveyor |
Steel loach | Twin screw and apron conveyors |
2.14. Workplaces must be cleaned of chips and dust in a manner that prevents the appearance of chips, dust and aerosols in the air of the work area.
2.10-2.14. (Changed edition, Amendment No. 1).
2.15. Chips and waste of titanium alloys must be collected in special metal containers (boxes, containers, etc.) labeled “Titanium waste.” As they accumulate and at the end of the shift, they should be removed.
2.16. Chips and waste of magnesium alloys should be collected in special containers installed at a distance of 3-4 m from metal-cutting machines and labeled “magnesium waste”.
Cleaning of chips and waste of magnesium alloys at workplaces must be carried out according to a schedule approved by the administration of the enterprise.
2.17. If it is necessary to control the dimensions of processed workpieces during operation of the equipment, special devices must be provided that allow measurements to be taken automatically, without removing parts.
Inspection on machines and removal of parts for inspection should be carried out only with the mechanisms for rotating or moving workpieces, tools and devices turned off.
(Changed edition, Amendment No. 1).
3. REQUIREMENTS FOR PRODUCTION PREMISES
3.1. Production facilities in which cutting processes are carried out must comply with the requirements of building sanitary standards and design rules for industrial buildings of industrial enterprises, approved by the USSR State Construction Committee, as well as norms and rules approved by state supervisory authorities.
Domestic premises must comply with the design standards for administrative buildings and premises of industrial enterprises, approved by the USSR State Construction Committee.
3.2. Areas for cutting cobalt, vanadium, molybdenum, titanium, zirconium must be separated from other rooms not related to this technology by insulating partitions and equipped with supply and exhaust ventilation and safety signs in accordance with GOST 12.4.026.
3.1, 3.2. (Changed edition, Amendment No. 1).
3.3. Shops, sections and cutting processing departments must be equipped with fire extinguishing means in accordance with GOST 12.4.009.
3.4. Openings in the walls of production premises, workshops and cutting areas intended for transporting materials, blanks and semi-finished products, finished parts and production waste must be equipped with devices and devices (corridors, vestibules, curtains, etc.) that exclude drafts, and also the possibility of fire spreading (automatic closing doors, latches, dampers, etc.).
3.5. Cutting processing of magnesium alloys should be carried out in specially designated rooms. It is permitted to place, in agreement with the state fire and sanitary inspection authorities, separate processing areas for magnesium alloys in general machining shops (except for polishing and grinding areas).
3.6. Ventilation requirements
3.6.1. To localize harmful substances (dust, small chips, aerosols of coolant, products of thermal-oxidative destruction) formed during cutting in the air of the working area and exceeding the maximum permissible concentration in accordance with GOST 12.1.005, machines and production equipment must provide for the possibility of suction from the processing area of contaminated air in accordance with Sanitary rules when working with cutting fluids and process lubricants.
To protect those working on the machine and people near the machine from flying chips and coolant, it is necessary to equip machines with protective devices that protect the processing area or part of it in which the cutting process is carried out.
The rooms in which coolant concentrates are stored and working solutions of process fluids are prepared must have supply and exhaust ventilation.
(Changed edition, Amendment No. 1).
3.6.2. Air ducts for removing dust from titanium and magnesium alloys must have smooth internal surfaces without pockets and recesses, eliminating the accumulation of dust, the shortest length and number of kinks. Curvature radii must be at least three diameters.
Air ducts of installations for suction of magnesium dust must be equipped with safety valves that open outward outside the explosive area.
3.6.3. The air removed by local suction devices when processing magnesium alloys on polishing and grinding machines must be cleaned in oil filters before it enters the fan. Filters and fans must be isolated from the cutting area.
To eliminate the danger of swirling and the formation of an explosive mixture of magnesium dust with air, it is not allowed to use dry centrifugal cyclones and cloth filters for cleaning.
3.6.4. To remove static electricity, dust collectors and air ducts of ventilation units must be grounded.
3.6.5. Air ducts from local suction and general ventilation must be cleaned according to a schedule approved in accordance with the internal documentation approval form adopted at the enterprise.
3.6.6. Gates, doors and technological openings must be equipped with air and air-heat curtains in accordance with the design standards for heating, ventilation and air conditioning approved by the USSR State Construction Committee.
3.6.5, 3.6.6. (Changed edition, Amendment No. 1).
3.7. Lighting requirements
3.7.1. Natural and artificial lighting of industrial premises must comply with the design standards for natural and artificial lighting approved by the USSR State Construction Committee.
3.7.2. The coefficient of natural illumination (NLC) on working surfaces must correspond to that indicated in Table 2.
It is allowed to reduce the KEO value in accordance with design standards for combined lighting. In this case, the illumination from the general artificial lighting system (as well as general in the combined system) should be increased by a step on the illumination scale.
table 2
with side lighting |
||||
Type of lighting | with top or top and side lighting | in an area with stable snow cover | in the rest of the USSR |
|
Procurement | Natural | |||
Combined | ||||
Mechanical, instrumental | Natural | |||
Combined | ||||
Note: Table 2 shows the standardized KEO values for buildings located in the III light climate zone of the USSR. For other light climate zones of the USSR, the standardized KEO values should be taken in accordance with the design standards for natural and artificial lighting approved by the USSR State Construction Committee.
3.7.3. In rooms with insufficient natural light and without natural light, artificial ultraviolet irradiation installations should be used in accordance with the Sanitary Standards for the Design of Industrial Enterprises and the Guidelines for the Design of Artificial Ultraviolet Irradiation Installations at Industrial Enterprises, approved by the USSR Ministry of Health.
3.7.4. With artificial lighting in procurement shops, the standardized illumination value of 150 lux must be provided by a general lighting system.
In mechanical, temperature-controlled and tool shops, a combined lighting system (general and local) should be used, in which the general lighting should be at least 300 lux.
The illumination of the working surface on manually operated machines must correspond to the values indicated in Table 3.
Table 3
Name of equipment, operations, workplaces | Illumination, lux |
1. Metal cutting machines: | |
turning, turning-backing, thread turning, jig boring, thread grinding, grinding, gear cutting, thread rolling; | |
turning-turret, turning-screw-cutting, surface grinding, cylindrical grinding, internal grinding; | |
milling | |
rotary turning | 1500; 1000** |
longitudinal planing | |
cross-planing | |
loboturning, drilling | |
slotting, broaching, cutting | |
2. Metalwork and patterning works, marking plates | |
_________
* Table dimensions more than 400x1600 mm
** Diameter of the workpiece is more than 2500 mm
On semi-automatic machines, automatic machines and CNC machines, the illumination indicated in Table 3 should be lowered by a step on the illumination scale in accordance with the Design Standards for natural and artificial lighting approved by the USSR State Construction Committee.
Illumination of 1500 lux must be provided in the working area of the OC and GPM. It is allowed to reduce illumination to 1000 lux when carrying out grinding and to 750 lux when carrying out drilling work.
When setting up, repairing and troubleshooting CNC, OC and GPM machines, the illumination should be 2500 lux.
3.7.5. For general lighting of a room, the ratio of maximum to minimum illumination should not exceed 1.3.
The pulsation coefficient should not exceed 20% of the total illumination.
3.7.6. When designing lighting installations for general lighting, it is necessary to take into account the safety factor: in mechanical and tool shops with fluorescent lamps with a power of 65 and 80 W and high-pressure discharge lamps - 1.5, with fluorescent lamps with a power of 40 W - 1.4, with incandescent lamps - 1 ,3; in thermoconstant lamps with discharge lamps - 1.3, with incandescent lamps - 1.15; in procurement shops with discharge lamps - 1.6, with incandescent lamps - 1.4.
When using fluorescent lighting on machines, the possibility of a stroboscopic effect must be excluded.
3.7.7. Cleaning of glass, window openings and skylights should be done at least 2 times a year.
Cleaning of lamps and lighting fixtures should be carried out: in mechanical shops of machine-tool factories, in temperature-constant and procurement shops at least 4 times a year; in machine shops of tool factories and tool shops - at least 2 times a year.
3.7.1-3.7.7. (Changed edition, Amendment No. 1).
3.8. Permissible noise levels at workplaces are no more than those specified in SN 3223.
4. REQUIREMENTS FOR STARTING MATERIALS
4.1. The mass fraction of chemical compounds included in working solutions of lubricant-cooling technological agents (LCTS) must comply with the technical conditions (TU) for the industrial production of cutting fluids, approved by the USSR Ministry of Health.
4.2. Antimicrobial protection of coolant should be carried out by adding biocidal additives (see reference Appendix 3) or periodic heat treatment or aeration of working solutions.
4.3. Thermal treatment of working coolant solutions should be carried out by heating to 75-80 °C, short-term holding and subsequent cooling in a regenerator or cooler to operating temperature.
Coolant aeration is carried out by mixing it with compressed air under a pressure of 0.2-0.3 MPa for 2-3 hours once a day.
4.4. The duration of use and frequency of coolant replacement are established based on the results of current monitoring of technological, physicochemical and microbiological indicators of the coolant, depending on the composition of the liquid, the material being processed, the type of technological operations, machine load and the number of work shifts per day.
It is recommended to replace emulsions used in metal blade processing operations for machines with an individual cooling system once a month, and in the summer - once every two weeks; when processing ferrous metals - at least once every two weeks; when processing alloys containing aluminum - once a week.
Oil coolants can be used for 3 months or more, subject to constant monitoring of the quality of the coolant, provided that the machine is systematically cleaned of chips and the filter is operating normally, as well as in the absence of intermittent work with ferrous metals.
4.5. Spent coolant and wash water must be collected in special containers.
The aqueous and oil phases can be used as components for the preparation of emulsions. The oil phase of emulsions can be supplied for regeneration or disposed of.
It is prohibited to discharge spent COTS into the general sewerage system and water bodies of reservoirs without first cleaning them from oil products.
4.1-4.5. (Changed edition, Amendment No. 1).
5. REQUIREMENTS FOR LOCATION OF PRODUCTION EQUIPMENT AND ORGANIZATION OF WORKPLACES
5.1. For workers involved in the technological process of cutting, comfortable workplaces must be provided that do not hamper their actions while performing work. At workplaces, an area must be provided on which racks, containers, tables and other devices are located for placing equipment, materials, blanks, semi-finished products, finished parts and production waste.
To work while sitting, the operator's workplace must have a chair (chair, seat) with adjustable backrest and seat height.
Ergonomic requirements when performing work while sitting and standing are in accordance with GOST 12.2.032, GOST 12.2.033.
At each workplace near the machine, there must be wooden ladders on the floor for the entire length of the working area, and a width of at least 0.6 m from the protruding parts of the machine.
5.2. The placement and rearrangement of existing technological equipment in workshops must be reflected in the technological layout, approved by the administration in consultation with the chief specialists and the labor protection service. Technological layouts for designed and newly built workshops, sections and cutting processing departments must be agreed upon with the territorial authorities of state sanitary and fire supervision.
5.3. Technological plans must indicate:
building elements (walls, columns, partitions, doorways, window openings, gates, basements, tunnels, main channels, mezzanines, galleries, hatches, wells, ladders, etc.), auxiliary premises, warehouses, storerooms, transformer substations, ventilation chambers , as well as utility rooms and other devices located in the area of the workshop, site or department;
the main dimensions of the building as a whole (width, length, span width, column spacing) and internal dimensions of isolated rooms;
technological and auxiliary equipment, lifting and transport devices (indicating load capacity), location of workplaces;
symbols of the necessary energy carriers (steam, gas, water, coolant, electrical voltage, etc.) and the place of their supply to each unit of metal-cutting equipment or equipment specification workplace with numbers according to the plan;
aisles, driveways, interoperational storage areas and indications of floor-standing vehicles acceptable in this case;
location of fire extinguishing equipment.
5.4. The width of workshop aisles and passages, the distance between metal-cutting machines and building elements must be established depending on the equipment used, vehicles, workpieces and materials being processed and must comply with the “Technological Design Standards”.
5.5. Passages and passages in workshops and areas must be marked with white demarcation lines at least 100 mm wide.
On the territory of a workshop or site, passages, driveways, and well hatches must be free and not cluttered with materials, blanks, semi-finished products, parts, production waste and containers. Installation of metal-cutting machines on well hatches is not allowed.
5.6. Released containers and packaging materials must be promptly removed from workplaces to places specially designated for this purpose.
6. REQUIREMENTS FOR STORAGE AND TRANSPORTATION OF STARTING MATERIALS, BLANKETS, SEMI-FINISHED PRODUCTS, coolant, FINISHED PARTS, PRODUCTION WASTE AND TOOLS
6.1. Safety requirements for transportation, storage and operation of abrasive and CBN tools are in accordance with GOST 12.3.028.
(Changed edition, Amendment No. 1).
6.2. Containers for transportation and storage of parts, workpieces and production waste - in accordance with GOST 14861, GOST 19822 and GOST 12.3.010. Operation of containers - in accordance with GOST 12.3.010. The container must be designed for the required load capacity, have inscriptions indicating the maximum permissible load, and be periodically inspected. The sling angle should not exceed 90°.
6.3. Loading and unloading of goods - in accordance with GOST 12.3.009, movement of goods - in accordance with GOST 12.3.020.
6.4. Storage and transportation of coolant should be carried out in accordance with GOST 1510 in clean steel tanks, tanks, barrels, cans and cans, as well as in containers made of tinplate, galvanized sheet or plastic.
Coolant fluids must be stored in premises that comply with the design standards for oil and petroleum products warehouses approved by the USSR State Construction Committee. The temperature of storage and transportation of coolant must be within the limits specified in the relevant standards for these products. In cases where they are not given, the recommended temperature for storage and transportation of coolant is from minus 10 to plus 40 ° C.
When transporting, filling and regenerating oil coolants, measures must be taken to prevent the ingress of water.
6.3, 6.4. (Changed edition, Amendment No. 1).
6.5. Waste titanium alloys should be stored in sealed containers in a specially designated dry room.
Oily small chips and dust of titanium alloys, as they accumulate, should be burned or buried in a specially designated area.
6.6. Chips and dust of magnesium alloys should be stored in closed metal containers. If special premises are available, chips and dust of magnesium alloys can be stored in open containers (except for magnesium-lithium alloys).
6.7. Where titanium and magnesium alloys are stored, there must be fire extinguishing means: dry sand, dolomite dust, powder flux, fire extinguishers charged with powder substances.
6.8. Wiping material (tips, rags, etc.) is stored in a special, tightly closed metal container in specially designated areas. As used cleaning materials accumulate, but at least once per shift, the containers must be cleaned.
7. REQUIREMENTS FOR PERSONNEL ALLOWED TO PARTICIPATE IN THE PRODUCTION PROCESS
7.1. Persons of the appropriate profession, specialty and qualifications who have undergone instruction and training are allowed to carry out technological processes of cutting.
Organization of training and instruction for workers, engineering and technical workers and labor safety employees - in accordance with GOST 12.0.004.
7.2. Persons entering work related to the processing of hazardous metals and their alloys using cutting fluids are subject to mandatory preliminary and periodic medical examination in accordance with the order of the USSR Ministry of Health.
7.3. Persons with a predisposition to skin diseases, suffering from eczema or other allergic diseases, as well as other contraindications provided for by the relevant lists of the USSR Ministry of Health, are not allowed to work with cutting fluids.
7.4. Workers who, due to the nature of their work, need to deal with the movement of goods by cranes and lifting devices, must undergo training as a slinger in accordance with the “Rules for the design and safe operation of load-lifting cranes”, approved by the State Mining and Technical Supervision of the USSR, at least once every 12 months. certification and have a certificate for the right to carry out these works.
7.5. Engineering and technical workers responsible for carrying out cutting processes (masters, technologists, senior foremen, deputy heads of workshops and heads of workshops), when appointed to a position, must undergo testing of knowledge of rules, norms and standards, the fundamentals of technological processes, safety requirements, devices and safe operation of metal-cutting, hoisting and transport, load-lifting and other equipment used, performance of loading and unloading operations, fire safety and industrial sanitation in accordance with their job responsibilities.
8. REQUIREMENTS FOR THE USE OF PROTECTIVE MEANS FOR WORKERS
8.1. To protect against the effects of dangerous and harmful production factors, workers and employees of workshops and cutting processing areas must be provided with special clothing, safety shoes and safety devices in accordance with Standard Industry Standards approved in the prescribed manner.
Personal protective equipment used during cutting must comply with the requirements of GOST 12.4.011.
8.2. The work clothes of those working in workshops and cutting processing areas should be periodically washed (dry cleaned) and stored separately from outer clothing. Dry cleaning and washing of work clothes should be centralized as they become dirty, but at least twice a month.
8.3. The overalls of those working in the processing of magnesium alloys must be systematically cleaned of settled magnesium dust, ventilated, stored in metal cabinets and washed at least once a week, followed by impregnation with fire-retardant compounds.
8.4. To protect the skin from exposure to coolants and toxic metal dust, dermatological protective agents (preventive pastes, ointments, biological gloves) should be used in accordance with GOST 12.4.068.
It is allowed to use other preventive pastes and ointments according to the recommendations of the State Sanitary Inspection authorities.
8.5. When preparing solutions of powdered and granular detergents for flushing cooling systems, workers must use masks and respirators.
8.6. To protect against static electricity, protective equipment must be provided in accordance with GOST 12.4.124.
8.5, 8.6. (Changed edition, Amendment No. 1).
8.7. Personal protective equipment specified in the technological documentation must be subject to periodic control inspections and tests in the manner and within the time limits established by the regulatory and technical documentation for them.
immediately after their preparation and during operation every 5 days. Frequency of monitoring coolant used on automatic lines: oil-based - at least once a month; emulsions - at least once a week; synthetic and semi-synthetic fluids - at least once every two weeks.
Additionally, control of the coolant can be carried out if its sanitary and hygienic properties deteriorate.
(Changed edition, Amendment No. 1).
9.3. Monitoring noise parameters at workplaces - in accordance with GOST 12.1.050.
9.4. The method for determining mechanical vibrations must be established in standards and technical specifications. Carrying out measurements - according to GOST 12.1.012.
Vibration parameters monitoring - according to GOST 12.4.012.
9.5. Illumination measurements should be carried out in accordance with GOST 24940. The illumination values in the room and in the treatment area must comply with clause 3.7, taking into account the measurement error of the device.
(Changed edition, Amendment No. 1).
9.6. Control of the level of electrostatic field strength - according to GOST 12.1.045.
(Introduced additionally, Amendment No. 1).
APPENDIX 1 (for reference). LIST OF THE BASIC RANGE OF TECHNOLOGICAL FLUIDS USED AS COOLANTS IN THE CUTTING OF METALS
ANNEX 1
Information
Synthetic and semi-synthetic coolants*
_____________
Aquol-1 (3-5)
Aquol-5 (2-3; 3-5)
Akvol-10M (2-5)
Aquol-10 (2-5; 5-10)
Aquol-11 (3-5; 5-10)
Aquol-12 (1.5-3)
Aquol-4 (1-3; 3-5; 5-10; 10-15)
Aquol-15 (3-5)
Aquapol-1 (3-15)
Sinho-2; 2M (3-5)
Sinho-6 (3-5)
Carbamol S-1 (1-3)
Carbamol P-1 (3-5)
MXO-62 (1-3)
Emulsions*
_____________
* The concentration of coolant in working solutions is indicated in parentheses, as a percentage.
Aquol-2 (1-10)
Aquol-6 (1.5-10)
NGL-205 (2-10)
RZ SOZH-8 (3-10)
VNII NP-117 T (1-3)
VNII NP-117 T (1-3)
IHP-45 E (5-10)
Ukrinol-1 (3-5)
Ukrinol-3P (up to 15)
SDMU-2 (3-10)
E-2 (3-10)
ET-2 (3-5)
EGT-(3-10)
EMUS (5-10)
Sintal-2 (3-5)
Carbamol E-1 (3-10)
LZ-EM/ZOT (3-10)
MXO (episode 60; 64) (3-5)
Ukrinol-1M (3-10)
Ukrinol-211 M (2-8)
Ukrinol-50 U (15)
Oil coolants
MP-1y; 2у; 2; 3; 4; 5u; 6; 7; 8; 9; 10; 99. Used as supplied MP-5u and 99. Can be used in the form of solutions in industrial oils from 5 to 100%
RZh-3
LZ-SOZH 1T
LZ-SOZH 1MO
LV-SOZH 2MO
LZ-SOZH 2MIO
LZ-SOZH 1MO
LZ-SOZH 1MIO
SEL-1
OSM-1; 2 (2k); 3; 4; 5
Ukrinol-14
APPENDIX 2 (for reference). EXAMPLES OF DESIGN OF NOZZLES FOR SUPPLYING COOLANT TO THE CUTTING ZONE
APPENDIX 2
Information
Single-channel nozzle for coolant supply using jet-pressure out-of-zone method
Multi-channel nozzle for supplying coolant using a jet-pressure out-of-zone method
Nozzles for coolant supply by hydro-aerodynamic method
a - with a foam plate; b - with a hard visor; c - with a rigid gear damper
Typical Coolant Spray Nozzle
1 - nozzles; 2 - distributor; 3 - tube; 4 - fitting
Nozzle for wide cutting area
1 - body;
2 - first distributor; 3 - second distributor; 4 - nozzles
APPENDIX 3 (for reference). LIST OF BIOCIDAL ADDITIVES TO COOLANTS
APPENDIX 3
Information
Azine - oxazolidine derivative (0.2-0.3)
Azine-1 derivative of oxazacycloalkanes (0.2-0.3)
Vasin - thiazine derivative (0.3)
Hexachorophene (0.01-0.2)
Kamtsid-1 (0.3)
Kamtsid-2 (0.15-0.25)
Catapin (0.15-1.0)
Merthiolate (0.0001-0.001)
Nitrocid-1 (0.06-0.15)
Nitrocid-2 (0.06-0.15)
Sodium orthophenylphenolate (0.6-1.25)
Sulfocide-4 is a product of the interaction of alkanolamine with formaldehyde, modified with a carbamic acid derivative (0.1-0.2)
Sulfocid-5 - composition based on a derivative of carbamic acid and alkanolamine (0.1-0.2)
Tetracide is a condensation product of formaldehyde with alkanolamine and alcohol (0.3)
Ukacid-2 - a triazine derivative activated by a nitroamine derivative of phenol (0.2)
Fermacid-10 (0.03-0.012)
Fermacid-12 (0.03-0.012)
Fermacid-13 (0.03-0.25)
Furacilin GF-10 (0.01)
Fomacid-13 - condensation product of formaldehyde with ketone (0.3)
Note. The recommended concentration of biocidal additives in the working coolant solution as a percentage is indicated in parentheses.
(Introduced additionally, Amendment No. 1).
The text of the document is verified according to:
official publication
"System of occupational safety standards." Sat. GOST -
M.: IPK Standards Publishing House, 2001
Labor protection is a system of legislative acts of socio-economic, technical, hygienic, therapeutic and preventive measures and means that ensure safety, preservation of human health and performance during the work process.
The state of safety and working conditions have an impact on the period of professional activity of workers, labor productivity, losses associated with injuries and illnesses at work, costs of benefits and compensation for working conditions. The Constitution of the Republic of Belarus (Article 2) proclaims that a person, his rights, freedoms and guarantees for their implementation are the highest value and goal of society and the state. In this regard, the main principle in the field of ore protection is the priority of the life and health of workers in relation to the results of work, establishing the responsibility of employers for labor safety, improving legal relations and management in this area. Currently, work is underway to develop a system of measures to ensure the implementation of state policy in the field of labor protection.
There are psychological and biological harmful production factors. The first includes physical overload during installation, fastening and removal of large parts, strained vision, monotony of work; the second factor includes pathogens and bacteria that appear when working with coolants.
Hazardous industrial factors include factors the impact of which can lead to injury. These include: unprotected moving and rotating parts and mechanisms of machine tools, moving products, chips of workpieces, high voltage in the electrical network.
The effect of harmful substances in the conditions of machine-building plants in most cases is aggravated by various associated environmental factors (high air temperature, noise, vibration, etc.)
At the production site, various harmful substances enter the air environment. The content of harmful substances in the air is regulated by GOST 12.1.005-88. The content of harmful substances in the air at the site does not exceed the maximum permissible concentrations. The dust content in the air does not exceed 6 mg/m2, and the concentration of oil mist aerosol is less than 5 mg/m2, which corresponds to the standards established by the above documents.
To protect workers and employees of workshops and areas from the effects of dangerous and harmful production factors, they are provided with special clothing, special footwear and safety devices in accordance with approved standards.
Measures to eliminate the causes of fire include preventive maintenance of electrical equipment and periodic removal of oily rags to a disposal point.
To evacuate people from the workshop premises, emergency exits are provided in the fireproof sides of the building.
Electric welding works.
At motor transport enterprises, when repairing parts, various welding methods are used: manual arc welding, semi-automatic and automatic welding, conventional or tubular electrode surfacing, and electric pulse surfacing.
Safety regulations provide for the performance of electric welding work in special booths. They are usually arranged against a dark wall with dimensions from 1.5x1.5 to 2.5x2.5 m. The height of the cabin walls is 1.8 m, for ventilation the walls are not 25 cm below the floor, the floors in the cabins must be made of brick or concrete. The walls of the cabin are painted on the outside with dark paint, and on the inside with matte paint containing zinc oxide (zinc white). This paint scatters light and at the same time intensively absorbs ultraviolet rays. The electric welder's table is covered with a steel or cast iron plate.
The distance between the electric welders' table and the cabin wall must be at least 0.8 m. They try to place the welding generator as close as possible to the welder's table, usually at a distance of 150 -200 mm.
For electric arc welding, alternating and direct currents are used. For welding metal with direct current, generators are used, in which the voltage automatically drops during short circuits.
When designing and organizing a welding room, passages and driveways with a width of 1.0~1.5 m and 2.5 m, respectively, must be provided. The height of the welding room is chosen to be 4.5-6.0 m.
To create healthy working conditions for welders, general exchange supply and exhaust and local exhaust ventilation must be provided. The temperature in the welding department room should not be lower than 12-15°C.
Often an electric welder has to work outdoors. In this case, tents, umbrellas or awnings made of fabrics impregnated with a fire-resistant composition must be provided for protection from precipitation, wind and sun, and for protection against radiation from the welding arc, it is necessary to install screens with a height of at least 1.2 m.
When performing electric welding work, invisible ultraviolet rays are emitted, which have a harmful effect on the retina and cornea of the eyes. If you look at the arc light with unprotected eyes, you will experience severe pain in the eyes, spasms of the eyelids, lacrimation, photophobia, and inflammation of the eyes. In such cases, it is recommended to consult a doctor immediately. First aid consists of ensuring complete rest for the eyes, applying cold lotions, and staying in a darkened room. Infrared (invisible) rays emitted by an electric arc cause more serious eye diseases with prolonged exposure.
To protect the welder's eyes from the rays of the electric arc, shields and helmets with protective glasses are used. They are made from matte black fiber. You should not use random colored glasses, as they cannot protect your eyes well from the invisible rays of the welding arc, which cause chronic eye disease.
Protective glasses (light filters) have different transparency. The darkest glass grade Z<::-500 применяют при сварке током 500 А, средней прочности марки ЗС-300 - 300 А и светлое ЗС-I00 - 100 А и менее.
When welding, dust is also generated from the oxidation of metal vapors. It has been established that near the welding arc torch the amount of dust can reach 100 mg per 1 m3 of air. The maximum permissible dust concentration in welding rooms is 3 mg per 1 m3. In addition to nitrogen oxides, welding produces carbon monoxide, the content of which, according to sanitary standards, should not exceed 10-20 mg per 1 m3 of air.
To remove harmful gases (oxides of copper, manganese, fluoride compounds, etc.) and dust above permanent welding areas, it is necessary to arrange local suction with the installation of ventilation hoods.
The maximum no-load voltage during welding should not exceed 70 V. Electric shock is especially dangerous when welding inside tanks, where the welder comes into contact with metal surfaces that are energized in relation to the electrical holder. Live parts must be well insulated, and their housings must be grounded. The welder must sit inside the tank on a rubber mat and wear a rubber helmet on his head.
Persons at least 18 years of age who have passed the appropriate tests and received a certificate from the qualification commission are allowed to perform welding work.
It is prohibited to carry out welding work at a distance of less than 5 m from flammable and flammable materials (gasoline, kerosene, tow, shavings, etc.).
If an electric welder works together with a gas welder, then in order to avoid an explosion of the acetylene-air mixture, electric welding work can be performed at a distance of at least 10 m from the acetylene generator.
The quality of manual electric welding depends on the qualifications of the welder, which is its main disadvantage. Recently, automatic and semi-automatic welding has been widely used in motor transport enterprises.
In semi-automatic welding, one of the operations is usually mechanized, and when welding with a metal electrode, the supply of electrode wire into the arc zone is mechanized.
Automatic submerged arc welding was developed in 1939-1940.
An electric arc burns between the metal of the part and the bare electrode wire, which is fed into the arc zone by the welding head. The arc can be powered by alternating current from a welding transformer or direct current from a welding generator. The electrode moves using a self-propelled drive of the stand along the part. Arc. burns under a layer of granular flux, which is poured from a hopper in front of the arc. Flux almost completely isolates the arc from the influence of air. During welding, part of the flux melts and, when cooled, forms a crust 6 that evenly covers the welding seam.
Automatic welding provides high quality, increases labor productivity and greatly facilitates the work of the welder.
During automatic electric arc welding, the metal melts under a layer of flux without causing any harmful effects on the eyes of the welder and surrounding workers. At the same time, dust emission is reduced; the use of uncoated bare electrodes eliminates the risk of poisoning. However, even with this method, there are cases of arc breakthrough through the flux layer with splashing of the molten electrode and hot slag, therefore, to protect against burns, the welder must work in special clothing and safety glasses.
Electrical pulse surfacing consists of applying an electrode wire to the deposited surface of a rotating part, which constantly vibrates and, touching the surface of the part, melts under the influence of an electric current. The molten metal of the electrode is transferred to the surface of the part. Cooling liquid, shielding gas or flux are supplied to the melting zone of the electrode and to the surface of the welded part. Metal melting and electrical discharge occur in a submerged liquid or protective gas environment.
The basic safety rules for electric pulse surfacing are as follows.
The lathe, control cabinet, feed motor, and generator motor or rectifier must be grounded. You must have a wooden grate or rubber mat near the installation. It is not allowed to touch switches and circuit breakers with wet hands.
During operation, a signal lamp must be lit on the panel and a general switch must be installed to turn off all electrical parts of the installation. It is not allowed to install parts on the machine or remove them from the machine while the switch is on.
To protect the eyes from the rays of the welding arc, the welder is required to use a shield or goggles with protective glasses (light filters) of ES of varying transparency. To protect against metal splashes and liquids, a removable or opening cover must be installed on the machine support.
Wiping ends, paper and flammable materials are not allowed on the machine.
FITTING WORKS.
When performing plumbing work, special attention should be paid to the organization of work, the condition of the tools and compliance with work safety rules.
Workbenches for metalwork must have a rigid and durable structure. To protect people nearby from possible injuries from flying pieces of the material being processed, workbenches should be equipped with safety nets with a height of at least 750 mm. Tools should be stored in workbench drawers, and workers should be given a portable toolbox or bag to carry them. To store used cleaning material, metal boxes with tight lids are provided. Hand tools must be in good condition. They discard it in the same way as devices, at least once a month in accordance with the established schedule.
Hammers and sledgehammers must meet the following requirements:
the strikers must have a smooth, slightly convex, not slanted or knocked down surface, without chips, gouges or cracks; wooden handles should be smooth and made of hard and tough wood (oak, birch, dogwood, beech, hornbeam, rowan), oval in cross-section and somewhat thicker towards the free end for self-jamming in the hand during swings and blows; the tool must be securely seated on the handle and wedged behind rough metal wedges; the axis of the handle should be located at right angles to the longitudinal axis of the tool; The length of the handle of a plumber's hammer should be 300-400 mm, and that of a sledgehammer 450-900 mm, depending on the weight of the tool.
Chisels, crosspieces, bits, cores, and notches must have a length of at least 150 mm and must not have beveled or knocked-off heads, cracks, burrs, dents, gouges, or hardening. When working with chisels, cross-cutters and other impact tools used for chopping metal and riveting frames, workers must be provided with safety glasses with safety glasses or with a protective mesh.
Hacksaws, screwdrivers, files, scrapers and other tools with pointed shanks must have wooden handles firmly attached to the shanks with a smooth and even surface. The length of the handles must be at least 150 mm. The handle is tightened with metal bandage rings.
Wrenches are strictly selected according to the size of the nuts and bolts. They should not have any wear on the throat, cracks, nicks or burrs, or non-parallelism of the jaws. It is prohibited to unscrew nuts using large wrenches with metal plates placed between the edges of the nut and the jaws of the wrench, or to EXTEND the handles of the wrenches by attaching another wrench or pipe. Sliding keys must not have any play in the moving parts.
Needle-nose pliers and pliers should not have chipped handles, cracks or burrs. The jaws of the needle-nose pliers must be sharp, without damage, and the jaws of the pliers must have an unfinished notch. A bench vise must have a working clamping screw and jaws with unmachined notches.
Before starting to work with pneumatic hand tools, you should check the reliability of the connection of the hoses to the tool, the serviceability of the hoses and the working element. No air should pass through the hose connection points. Hoses must be attached to fittings and nipples using tie rods and clamps, but not with wire. Immediately before connecting, the hose should be purged to remove contaminants. In this case, the air stream is directed upward. Air supply is allowed only after the tool has been installed in the working position. Idle operation of the tool is permitted only for testing it before starting work and during its repair. Hoses can only be connected or disconnected after turning off the air supply. When working, it is prohibited to: direct a stream of compressed air at people; fracture, tangling and intersection of hoses with electric welding wires and gas welding hoses, with ropes, as well as wrapping people and equipment with hoses. During breaks in work in the event of a hose break or in the event of any malfunction, you should immediately turn off the tool by closing the valve on the air line. Pneumatic tools (riveting and chipping hammers, drilling and grinding machines) must be equipped with noise suppressors and compressed air release." "Persons working with pneumatic tools; must be provided with vibration-proof gloves and special shoes.
Power tools (nuts and pin drivers, grinders and polishers, thread cutters) must be stored in the tool room and issued to the worker only after a preliminary check, together with protective devices (rubber gloves, mats, dielectric galoshes). Only power tools with proper insulation of live parts may be used. Electric tools with a metal casing must be equipped with a grounding device. In premises with working conditions without increased danger, it is permitted to use power tools with a voltage of no higher than 220 V. In premises with working conditions with increased danger and outdoors, power tools with a voltage no higher than 42 V should be used. If the power of a 42 V power tool is insufficient, you can work with a power tool with voltage up to 220 V inclusive, providing a protective disconnecting device or reliable grounding of the power tool body with the mandatory use of protective equipment. In particularly dangerous working conditions (inside metal tanks, boilers), it is allowed to use power tools only with voltage up to 42 V inclusive, with the mandatory use of protective equipment. When using a power tool with double insulation (the housing is made of dielectric materials), grounding or grounding is prohibited, and the use of protective equipment is not necessary. The power tool must only be connected to the electrical network using plug connections. A specially designated person with a safety qualification group of at least III checks the condition of the wire insulation and protective grounding of the power tool at least once every 6 months.
When working with a power tool, it is prohibited to: hold it by the wire or working part; insert or remove the working element until the engine stops completely; work at height from a portable ladder; connect to the network by twisting wires; remove protective covers; work outdoors in the rain or snow. During operation, ensure that the connecting wires do not touch hot, wet or oily surfaces. During breaks and when turning off the current in the power supply network, the power tool must be disconnected from the network. The use of power tools is permitted to persons who have undergone training and are familiar with the rules for handling them.
Conclusion
While taking an automotive practice course at JSC Spetsavtopredpriyatiye, I became familiar with the production and organizational activities of this enterprise, with the purpose of the main departments, sections, workshops and other areas.
I studied the structure of the enterprise, departments, workshops, management methods in such industries and methods of their implementation using the example of Spetsavtopredpriyatie OJSC. I got acquainted with their equipment, with technologies for restoring parts, and understood the specifics and nature of the work of employees of motor transport enterprises. In addition, I became familiar with the tools, measuring instruments, equipment used (stands, lifts, etc.) I understood the structure of the technical service of the enterprise and the relationships between its individual divisions and services.
While doing an internship at the OJSC Spetsavtopredpriyatiye enterprise, I understood the significance, difficulties and achievements of enterprises of this kind and purpose, with their extremely important role in the economic activities of a modern city.
As a result of the development of the technological process for the driven clutch disk of the ZIL-130 car, work was carried out to restore the part in accordance with modern technical requirements. All technology for repairing the part has been followed, which ensures the durability and wear resistance of the part for the entire service life of the unit.
Bibliography
1. Metal-cutting machines: Textbook for mechanical engineering universities. Ed. V.P. Pusha. – M.: Mashinostroenie, 1985. – 256 p.
2. Labor protection in mechanical engineering. Ed. E.Ya. Yudina. – M.: Mashinostroenie, 1983.
3. Design of technological processes of mechanical processing in mechanical engineering. Textbook allowance. V.V. Babuk et al. Ed. V.V. Grandma. – Mn.: Vysh.shk, 1987. – 255 p.
4.Metal-cutting machines: Textbook for technical schools. N.N. Chernov. – M.: Mashinostroenie, 1988. – 416 p.
In order to avoid injury and create safe working conditions for the turner, in addition to the general rules, specific rules must be observed, which are determined by the characteristics of the turning group machines. They are as follows:
Before turning on the machine:
· first make sure that launching it does not threaten anyone
danger;
· the machine must be grounded and protected by a protective shield;
· the worker - machine operator must be dressed in special clothes (robe, overalls), and have a beret on his head; To protect your eyes from chips and COTS, you must use safety glasses;
· check the presence and serviceability of:
Grounding devices;
Guarding of drives, gears, live parts;
Chip protection devices;
Cutting, measuring, fastening tools and
devices;
· when using devices equipped with pneumatic, hydraulic or electromagnetic drives, carefully check the condition of air and liquid supply communications, electrical wiring; it is necessary to thoroughly clean the spindle from dirt and thoroughly wipe it;
· check the oil level using the control eyes in the gearboxes, feed boxes and in the apron; pour into all oilers where manual lubrication is provided (according to the machine’s passport);
· check the condition of the guides, clean them of dirt and lubricate them;
While the machine is running:
· install and remove cartridges, faceplates and other devices using a lifting device; securely and rigidly fasten the part to the machine;
· do not use worn-out technological equipment (chucks, centers, adapter bushings, etc.).
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· when securing a workpiece in a chuck or faceplate, grab the part with cams for as long as possible; the protruding part of the workpiece should have a length of no more than 2-3 diameters; if larger, use a tailstock.
· it is prohibited for the jaws, after securing the part, to protrude beyond the outer diameter of the chuck or faceplate by more than 1/3 of the length of the jaws;
· when fixing the part in the centers:
Check the serviceability of the centers and their coincidence along the center line,
Make sure that the part rests on the center,
Fasten the tailstock securely so that the part can rotate in the centers without much effort, and do not allow the quill to overhang;
· when processing in centers, use safe drive chucks and clamps or install a guard on the drive chuck, do not allow the fingers of the drive chuck to protrude beyond the rim of the clamp;
· when processing workpieces with a length of more than 12 diameters, as well as with high-speed and power turning of workpieces with a length of more than 8 diameters, it is necessary to use steady rests;
· install cutters that are properly sharpened and in good working order (no cracks, breaks, solid fastening of carbide plates, etc.);
· for the correct installation of the cutters relative to the center axis and the reliability of their fastening in the caliper, use special measuring spacers equal in length and width to the cutter surface.
· cutters should be secured with the minimum possible overhang from the tool holder (no more than 1.5 times the height of the cutter holder) and with at least two bolts;
· do not leave tools in the tailstock that are not used when processing this workpiece;
· monitor the serviceability of the tool, promptly change dull tools;
· ensure the correct supply of COTS to the cutting zone: it should be supplied to the cutting zone in a uniform stream that prevents splashing
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Use correct work practices:
Bring the cutting tool to the rotating workpiece, and turn off its rotation after retracting the tool,
Do not support the part of the workpiece being cut with your hand.
When performing manual operations, move the caliper and tailstock to a safe distance,
When polishing, use pressure pads;
· do not take or pass any objects through a working machine, do not tighten bolts and other connecting parts of the machine while moving;
· do not slow down the rotating spindle by pressing your hand on the machine tool or workpiece;
· measure the workpiece only after turning off the clutch, retracting the caliper and tailstock to a safe distance;
· do not lean on the machine and do not place workpieces, tools and other objects on the guides of the machine;
· remove chips from the machine only with a special hook, brush or scraper;
If vibration occurs, stop the machine and take measures to eliminate it: check the fastening of the tool and parts, reduce the tailstock overhang, check the centers, change the cutting modes.
After finishing work:
· turn off the machine;
· tidy up the workplace;
· clean and lubricate the machine;
· Carefully fold the blanks and finished parts.
In emergency situations
Stop the machine immediately:
· if voltage is detected on the metal parts of the machine
· the electric motor operates in two phases (hums),
· the grounding wire is broken,
· during a power outage,
when vibration occurs,
· when the fastening of a part or cutting tool is loosened.
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1.9 SOTS and methods of approaching the cutting zone.
Lubricating and cooling technological means (LCTS) are widely used in machining to improve the machinability of materials and are used in the form of liquids, gases, greases and solid lubricants. Of these, the most widely used are liquid coolants, which are commonly called cutting fluids (coolants).
COTS are intended for lubrication of friction surfaces, cooling of the cutting tool and the workpiece, facilitating the process of metal deformation, timely removal of chips and tool wear products from the cutting zone, as well as for temporary protection of products and equipment from corrosion. Thanks to this, COTS largely determine the efficiency and reliability of operation of numerous and varied metal processing equipment, namely: they increase the durability of cutting tools, improve the quality of products, reduce cutting forces and power requirements.
In mechanical engineering practice, coolant is most often supplied to the cutting zone by irrigation in the form of a freely falling jet. In Fig. Figure 1 shows an example of the practical implementation of a coolant supply circuit on a lathe (rear view)
Figure 14. Coolant system on a lathe
The lubricant and cooling liquid from the container in the left cabinet of the machine is supplied by a pump through a flexible hose into the pipeline with a sample
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The amount of coolant supplied to the cutting zone is regulated using a plug valve. The used coolant flows into a trough and is discharged into a container to the pump. The fluid pressure in the supply line must be sufficient to lift the fluid to the level of the nozzle nozzle position. Typically it is in the range from 0.02 to 0.05 MPa and is provided by a pump. The amount of coolant supplied to the cutting zone depends on the type of coolant (water or oil), the type of operation being performed and the intensity of the cutting mode. On universal machines weighing up to 10 tons, liquid is supplied in quantities from 2 to 20 l/min. In some cases of machining (on multi-spindle automatic machines, gear-processing machines and others), the coolant flow is used simultaneously to carry away chips. The amount of coolant for these cases is calculated using experimental and statistical formulas.
Figure 15. Nozzle attachments for flood coolant supply
At various technological operations, depending on the type, size and design of the tool used and the desired width of coverage of the cutting zone by the coolant jet, nozzle attachments of various types are used. Features of their designs are shown in Fig. 2. The nozzles of the coolant supply system on lathes are a metal tube with a tapered end
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If more intensive cooling of cutting tools is necessary, their internal cooling is used, which consists of passing coolant through internal channels in the body of the tool. Most often, internal cooling is used in axial tools such as drills, countersinks, reamers, broaches, taps and other similar tools, but can be used in any other tools. In Fig. Figure 3 shows cutters with internal cooling. In the body of the cutter 1 there is a cavity, the surface of which is covered with a porous material (Fig. 3, a) moistened with coolant.
Figure 16. Cutters with internal cooling
When cutting, the liquid in the cutting part of the cutter evaporates and condenses in the “cold” clamping part of the cutter. Through the porous material 2 it again flows to the cutting part. Cutters can have closed (Fig. 3, b) and flow-through (Fig. 3, c) cavities.
Chapter 2. Practical part
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2.1 Development of a drawing of the “Saddle” part in a graphic editor
"Compass" is a family of computer-aided design systems with the ability to prepare design and construction documentation in accordance with the standards of the ESKD and SPDS series.
Developed by the Russian company Askon. The name of the line is an acronym for the phrase “complex of automated systems.” Trademarks are written in capital letters: “COMPASS”. The first release of Compass (version 1.0) took place in 1989. The first version for Windows, Compass 5.0, was released in 1997.
Programs of this family automatically generate associative views of three-dimensional models (including sections, sections, local sections, local views, arrow views, views with a break). All of them are associated with a model: changes in the model lead to changes in the image in the drawing.
Standard views are automatically built in a projection relationship. The data in the title block of the drawing (designation, name, weight) is synchronized with the data from the three-dimensional model. It is possible to link three-dimensional models and drawings with specifications, that is, with “proper” design, the specification can be obtained automatically; in addition, changes in the drawing or model will be transferred to the specification, and vice versa.
Compass-3D Home"
Released in 2011, the free Compass-3D Home system is intended for use at home and for educational purposes. As of 2013, the system included over 50 applications for mechanical engineering, instrument making and construction. The “Compass-3D Home” system comes with a built-in interactive textbook “ABC COMPASS” with lessons on mastering 3D technology.
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2.2 Manufacturing the part according to the route map
For cutting metals and parts, turning, milling, planing, drilling machines, as well as roughing and grinding, sharpening, etc. are used.
Injuries are associated with impacts from poorly secured workpieces, both on lathes and on drilling machines, etc. When drilling, a part that is not secured in a vice is often torn out of the hands (at the exit of the drill) and, if this part is large enough and has sharp edges, the problem may end not only with hand injury, but also with serious abdominal injury.
Chips often cause eye injuries (when working without safety glasses), cuts to hands (when cleaning them), and sometimes twisted shavings that fall on a rotating part can cause deep wounds to the face and neck. There are frequent impacts from a key forgotten in the chuck of a lathe, from the end of the bar being processed protruding beyond the spindle, from a collapsing cutting tool (cutter, drill, etc.). Hands get wrapped around the spindle or chuck of a drilling machine when trying to slow it down when working with gloves on; wrapping dangling ends of workwear and hair on rotating parts (often with severe and fatal consequences).
It is dangerous to work on abrasive grinding machines without guards or with abrasive wheels that have not been tested for strength: both on stationary machines and on hand tools with a flexible shaft. There are many examples of circle breaks and worker injuries. Thus, the personal driver of the director of the enterprise, while waiting for a long time for a trip, went into a repair shop, took a portable grinder with a flexible shaft and began to grind the welds of a metal box for a hunting rifle, which he was making for personal purposes. The protective cover on the grinder was missing. Suddenly the circle split, one of the fragments hit the driver in the neck, cutting through an artery. Death occurred within seconds. There were a lot of violations here, both organizationally and technically (access to equipment without instructions, a faulty grinder, in addition, as it turned out during the investigation, the entire batch of abrasive wheels of this type did not have a mark indicating that they had passed a strength test, etc.) .
In accordance with "POT RM-006-97. Interindustry rules for labor protection during cold processing of metals", approved by Decree of the Ministry of Labor of Russia dated October 27, 1997 No. 55, at each machine operator’s workplace there must be a bedside table for storing tools, a rack for placing parts, above the machines for processing heavy parts there are lifting and rotating lifting mechanisms, under the feet at the workplace there are wooden gratings.
Before starting work, work clothes are fastened so that there are no hanging ends, hair is tucked under the headdress (the danger of wrapping around the spindle, workpiece, drill). For the same reason, you cannot work in mittens.
Chips from machines are removed with brushes, hooks, scoops, scrapers, but not with bare hands (danger of cutting) and not by blowing them off with compressed air (danger of getting into eyes).
The machine room should have general lighting, preferably white fluorescent lamps. The processing area is illuminated with local lighting lamps (built-in, attached) with a supply voltage of no more than 24 V (for incandescent lamps). In the area where parts are processed, illumination should be created without sharp shadows, eliminating the appearance of a stroboscopic effect with illumination for lathes, grinding, sharpening machines - 2000 lux, drilling machines - 1000 lux, milling machines - from 1500 to 2000 lux.
Lathes To protect against parts accidentally flying out of the chuck or chips, they are equipped with protective opening screens (transparent from the worker’s side). To prevent the winding of protective clothing around the lead screw and shaft, they are also protected.
The ends of the processed bar metal protruding beyond the spindle of the machine are protected along the entire length by circular casings - pipes mounted on supports. There is a great danger here that the protruding end of the rod will bend and hit the worker. We recently investigated a similar fatal accident.
During operation, the workpiece should be securely fastened in the chuck. When machining viscous material, very dangerous twisted chips can form. If it is long enough it can overwhelm and seriously injure a worker. To crush such chips, cutters with special sharpening or with chip breakers are used. To protect against finely crushed chips (processing light alloys, plastics), dust collectors are used. The cutters are installed strictly in the center of the workpiece with as little protrusion from the tool holder as possible (the vibration of the machine and the likelihood of the cutter chipping are reduced - the risk of eye injury).
When operating the machine, it is prohibited to: use chucks with worn working surfaces of the cams, with a non-rotating center of the tailstock; slow down the rotation of the spindle by hand, measure the workpiece (with a clamp, gauge, micrometer, etc.) until the machine stops and the support is retracted to a safe distance.
The braking time of the spindle of a universal lathe after turning it off should not exceed 5 s (when processing parts with a diameter of up to 500 mm) and 10 s (up to 630 mm).
Drilling machines must have: a device that prevents spontaneous lowering of the traverse, trunk, bracket; as well as a vice, firmly attached to the machine table, into which the workpiece should be clamped.
When drilling, holding the part with your hands is prohibited (risk of jamming the drill at the exit, turning the part and injuring your hands). The processing area in drilling machines is fenced off. Remove chips from drilled holes only after the machine has completely stopped and the tool has been removed. Do not use drills, countersinks, reamers, etc. with worn shanks, you cannot work with gloves or stop the rotating chuck with your hands.
On milling machines The processing area is fenced off with screens. Do not use disc cutters with cracks or broken teeth. After installing the cutter, its radial and axial runout should not exceed 0.1 mm. When changing the workpiece or measuring it, the machine should be turned off. The chips are removed from the rotating cutter using brushes with a handle length of at least 250 mm.
Planing machines installed so that there is a distance of at least 0.7 m between the wall and the movable table at the moment of its greatest extension. These machines have feed mechanisms, maximum table travel and reversing mechanisms.
Grinding and abrasive grinding machines, including manual, portable with a flexible shaft, are equipped with protective covers covering the abrasive wheel and inspection screens interlocked with the start-up system (it is impossible to start the machine without installing the protective screen in place), as well as a local ventilation suction.
The protective casing is made of sheet carbon structural steel (must withstand the load from the collapsing abrasive wheel when it breaks). It should cover the abrasive wheel on all sides, leaving only a sector for processing the part. The angle of this sector (the opening angle of the protective casing) should not exceed 90°, and no more than 65° of this sector should be located above the axis of the circle. For hand-held portable sanders with a flexible shaft, the opening angle of the casing is allowed up to 180°.
A protective (transparent) screen with a thickness of at least 3 mm protects the worker from abrasive chips.
When installing, a new abrasive wheel is checked for cracks by lightly tapping it with a wooden hammer. If the sound of the impact is clear and ringing, then the circle is without cracks, but if it is rattling, then it has cracks and cannot be installed. If two wheels are installed on the machine, then their diameters should not differ by more than 10%. During installation, cardboard gaskets 0.5-1.0 mm thick are placed between the abrasive wheel and the flanges.
The machine tool rest is installed so that the gap between its edge and the abrasive wheel is no more than 3 mm and the product touches the wheel at the level of its center or higher, but not more than 10 mm.
On grinding and cutting wheels with a diameter of 250 mm or more, as well as on grinding wheels of hand-held grinding machines, colored stripes must be applied: yellow - on wheels with a working speed of 60 m/s, red - 80 m/s, green - 100 m/s , green and blue – 120 m/s. The specified speeds must not be exceeded (destruction of the circle may result in injuries, including fatal ones).
All abrasive grinding wheels are tested for mechanical strength on test benches, setting them to a test speed 1.5 times higher than the working speed, with holding in this mode for 5 minutes - for wheels with a diameter of 150 mm or more, and 3 minutes - for wheels with a diameter of less than 150 mm.
Grinding wheels that do not have test marks cannot be installed on the machine. Before starting work, the circles are checked at idle speed: circles with a diameter of up to 150 mm - for 1 minute, 150–400 mm - 2 minutes, with a diameter of more than 400 mm - 3 minutes.
Grinding wheels with a diameter of more than 250 mm at any rotation speed, as well as with a diameter of more than 125 mm with an operating speed of over 50 m/s, must be balanced together with the faceplate before installation on the machine.
It is prohibited to work on the side (end) surfaces of the circle unless it is specifically designed for this purpose. During operation, the residual diameter of the grinding wheel must be at least 10 mm larger than the diameter of the flange. Do not slow down the circle by pressing on it with any object (risk of breaking the circle).
Metal cutting carried out with hand scissors, sawing machines, guillotine shears and other mechanisms.
Hand lever scissors are securely mounted on special racks or workbenches, tables, stands.
Mechanical scissors are equipped with safety devices on the workplace side to prevent fingers from getting under the knife and the clamps. It is forbidden to use scissors if there are dents, gouges, cracks in any part of the knife, if the cutting edge is dull or if the gap between the cutting edges increases above the standard.
In circular saw machines, saw blades are covered with casings, the opening angle of which on the cutting side is adjusted depending on the size and profile of the metal being cut. It is not allowed to use circular saws with cracks, broken teeth or fallen blades.
For band saws, the entire non-working part of the saw is also protected. When processing small objects on circular and band saws, special feeding and fixing devices are used to prevent the presence of fingers there.
Guillotine shears (for cutting sheet metal) are equipped with mechanized stops to limit the supply of the sheet being cut, controlled from the workplace; mechanical or hydraulic clamps for fixing the metal being cut; safety devices that prevent fingers from getting caught under clamps or knives (must be interlocked with the trigger mechanism, which does not allow the trigger to be activated when behind the hand guard).
- See: "GOST 12.2.009-99. Interstate standard. Metalworking machines. General safety requirements", put into effect by Decree of the State Standard of Russia dated 02/11/2000 No. 34-st.
By order of the Ministry of August 25, 1982 No. 087-16
the introduction period is set from 01.01-1984.
This standard establishes general safety requirements for the development and implementation of processes for mechanical processing of metals by cutting (hereinafter referred to as cutting) on metal-cutting machines and automatic lines.
I. GENERAL PROVISIONS
1.1. The development of technological documentation, organization and implementation of technological processes of cutting processing must meet the requirements of the “Sanitary Rules for the Organization of Technological Processes and Hygienic Requirements for Production Equipment” approved by the USSR Ministry of Health, as well as this standard.
1.2. In technological processes of machining by cutting, the following dangerous and harmful production factors may affect workers:
moving parts of production equipment and moving workpieces, parts and materials;
increased noise level in the workplace;
increased content of dust, harmful vapors and aerosols in the air of the working area;
increased voltage values in an electrical circuit, the closure of which can occur through the human body;
increased level of vibration;
sharp edges, burrs and roughness on the surface of workpieces and parts;
increased level of static electricity;
toxic, irritant and other effects on the human body depending on the material used;
location of workplaces at a significant height relative to the floor surface;
fire and explosion hazard.
1.3. The concentration of harmful substances formed in the air of the working area during cutting should not exceed the standards specified in GOST 12.1.005-76. Noise levels at workplaces should not exceed the values established by GOST 12.1.003-76.
1.4. The optimal and permissible values of temperature, relative humidity and air velocity in the working area of the production premises of the workshop must comply with the requirements of GOST 12.1.005-76, section I and “Sanitary standards for the design of industrial enterprises” approved by the USSR State Construction Committee *
1.5. Conveyors used for interoperational movement of goods (workpieces, parts, etc.) during cutting must meet the requirements.
1.6. Machine tools used for cutting must comply with the requirements of GOST 12.2.029-77.
1.7. The tool used for cutting must meet the requirements of GOSTs, specifications and technological documentation.
1.8. Permissible values of vibration parameters that are transmitted from operating machines and other equipment to workplaces and to the hands of workers must not exceed the standards established in GOST 12.1.012-78, "Sanitary standards for the design of industrial enterprises", approved by the USSR State Construction Committee and "Sanitary standards and rules for working with pneumatic tools, mechanisms and equipment that create vibrations transmitted to the hands of workers,” approved by the USSR Ministry of Health.
1.9. Workshops and areas for cutting must be equipped with fire extinguishing means in accordance with the requirements of GOST 12.4.009-75, industry “Fire Safety Rules” and the guidance material “Categories and classes of production for explosion, explosion-fire and fire hazards and fire protection equipment”, approved Ministry.
110. Based on this standard, taking into account the specifics of work in associations, enterprises and organizations in the industry, occupational safety instructions must be developed, and existing instructions must be brought into compliance with the requirements of this standard.
2. SAFETY REQUIREMENTS FOR TECHNOLOGICAL PROCESSES
2.1. General requirements.
2.I.I. Safety requirements for cutting processes must be set out in the technological documentation in accordance with the requirements, section 2.
2.1.2. The presentation of safety requirements in technological documentation should be carried out in accordance with RD50-134-78 "Methodological instructions for monitoring the completeness of statements of occupational safety requirements in design and technological documentation", approved by the Resolution of the USSR State Committee for Standards.
2.1.3. Before installation on the machine and automatic lines, the workpieces (parts) and fixtures being processed must be cleaned of chips and oil, especially the contacting base and fastening surfaces necessary to ensure reliable fastening.
2.1.4. The fastening of workpieces (parts) and tools to the machine must be strong and reliable, regardless of their size and weight.
If the fastening of the tool, workpiece (part) is loosened, or if the cutting tool jams during operation, work on the machine must be stopped.
2.1.5. Installation of tools, workpieces (parts) and devices on the machine and their removal from the machine should be done after disconnecting and stopping the rotating and moving parts of the machine.
2.1.6. Installation and removal of workpieces, parts weighing more than 8 kg, as well as tools and devices weighing more than 20 kg on universal and specialized machines must be carried out using lifting devices, in accordance with the requirements, section I,
2.1.7. Tools should be changed using devices specially designed for this purpose, specified in the technological documentation. To remove the tool, it is necessary to use wrenches, hammers and drifts made of material that prevents the separation of particles upon impact.
2.1.8. When processing brittle metals (cast iron, bronze, etc.), which produce loose and finely crushed chips, as well as when crushing steel chips, it is necessary to use protective devices (for example, chip evacuation devices, transparent screens or individual protective shields, etc.) for protection of workers from flying particles.
2.1.9. When processing tough metals that produce steel or non-ferrous shavings, it is necessary to use cutters with special chip-breaking devices.
2.1.10. If it is impossible to use chipbreakers on the machines, it is allowed to remove chips from the cutting zone and remove them from the machine using the appropriate devices specified in the technological documentation.
2.1.11. The placement of the hoses through which the cutting fluid (coolant) is supplied to the cutting zone must be done in such a way that the possibility of their contact with the cutting tool and moving parts of the machine is excluded.
2.1.12. When cutting using coolant and oils, protective devices must be used to prevent splashing of coolant and oils outside the machine.
2.1.13. Tanks and other containers intended for collecting coolant should be cleaned of sediment (dust, chips, sludge, etc.) as necessary” within the time limits specified in the instructions.
2.1.14. Blowing compressed air onto the surfaces of workpieces, parts and machines is not allowed.
2.1.15. When cutting metals with abundant release of harmful substances (dust, aerosols, gases, vapors), the release points should be equipped with local suction,
2.1.16. While the machine is operating, braking the rotating parts by hand pressure is not allowed. Braking of the rotating parts of the machine must be carried out only by braking devices.
2.1.17. When removing cutters, overthrows and other cutting tools from the spindle, it is necessary to place an elastic gasket or other device in place of a possible fall.
2.1.18. The removal of chips from machines and areas must be mechanized (conveyor or auger mechanisms, etc.). From the workplace of machines that do not have mechanical devices for removing chips, it is allowed to remove chips using easily movable and convenient hand carts.
2.1.19. When working on large-sized machines, if it is not possible to observe the processing of the workpiece (part) and service the machine directly from the workshop floor, it is necessary to use stable and durable stands specially designed for this purpose or special platforms with fences, in accordance with the requirements.
2.1.20. When preparing a machine or automatic lines for operation, it is necessary to remove all foreign materials (finished products, production waste, etc.), and also check the reliability of the fastening of the workpieces (parts) and tools.
2.1.21. Changing tools and removing workpieces (parts) from machines and automatic lines should be carried out in accordance with the requirements specified in the technological documentation.
2.1.22. All protruding rotating, moving parts of machines and automatic lines, as well as tools and workpieces (parts) that may pose a danger during operation, must be protected by casings or other protective devices.
2.1.23. It is not allowed to work on a machine with the protective devices removed, or to keep the protective devices open while the machine or automatic line is running.
2.1.24. Cutting tools with soldered plates should be used only after checking the quality of soldering by technical control (QC) in accordance with the requirements specified in the technological documentation.
2.1.25. Pipes supplied to machines, hoses used for laying electrical wiring, supplying air and liquid (used to secure workpieces, parts in pneumatic, hydraulic and electromagnetic devices), laid in places where mechanical damage is possible, must be fenced*
2.1.26. For storing small workpieces in accordance with the technological documentation, special containers must be used that allow convenient transportation and safe slinging when transported by crane. The shooting range must be durable and designed for the required load capacity*
2.1.27. When installing workpieces (parts) using lifting devices on the machine, workers are not allowed to be between the machine and the workpiece (part).
2.2. Safety requirements for turning
2.2.1. When securing a workpiece (part), the jaws should not protrude from the chuck or faceplate beyond the outer diameter.
If the jaws protrude, the chuck must be replaced or a special guard installed.
2.2.2. When processing in the centers of workpieces (parts) with a length equal to 10-12 diameters or more, as well as when high-speed and power cutting of workpieces with a length equal to 8 diameters or more, it is necessary to use additional supports (rests),
2.2.3. When installing and securing the part in the centers, it is necessary to use safe clamps or driving chucks, and also check the fastening of the tailstock and quill. The use of centers with worn cones is not allowed.
2.2.4. Securing workpieces (parts) with worn-out or clogged centers is not allowed.
2.2.5. (screwing in a chuck or faceplate by sudden braking of the spindle (by reversing) with the use of random objects, etc. is not allowed. When screwing in a chuck or faceplate, it is necessary to use a safety mandrel.
2.6. During the operation of rotary machines, rotating faceplates and workpieces (parts) processed on them must be protected along the circumference by sliding or descending casings, shields or other protective devices.
2.2.7. It is not allowed to work on a lathe without devices that prevent self-unscrewing of the chuck and faceplate during reverse.
2.2.8. Installation and fastening of threaded nuts in a chuck or fixture on a thread lathe must be done in such a way that the possibility of the tool flying out or breaking is excluded.
2.2.9. When cutting bar material, the uncut end of the bar protruding from the spindle must be placed in
a special fence that covers it completely. The design of the fence must reduce noise when the rod rotates to the permissible noise level in the workplace in accordance with the requirements of GOST 12.1,003-76.
2.2.10. When working on multi-spindle semi-automatic lathes and aggregate machines operating in an automatic cycle, installation and removal of workpieces (parts) should be done only at the loading position.
2.2.11. To install the cutter on the machine, it is necessary to use only special spacers equal in length to the entire supporting plane of the cutter. The attachment of the cutter must be strong and reliable. If necessary, the cutter overhang should be indicated in the technological documentation.
2.2.12. For stripping, filing and other finishing operations on machines, it is necessary to use special devices (pliers, holders, etc.) to ensure the safe performance of these operations. The use of such devices must be indicated in the technological documentation. The use of a scraper when removing burrs is not allowed.
2.3. Safety requirements for drilling and boring processing
2.3.1. Checking the correct installation of the workpiece (part) on the boring machine should be done using instruments (thicknesser, indicator, etc.) specified in the technological documentation.
2.3.2. It is not allowed to leave the slide protruding beyond the circumference of the support on a horizontal boring machine."
2.3.3. When installing and removing boring heads, it is necessary to place pads (wooden, textolite, plastic or made of soft metals) under them on the machine table.
2.3.4. When installing and aligning workpieces (parts) on a boring machine, alignment of the workpiece (part) should be done using the devices specified in the technological documentation.
2.3.5. The wedge securing the tool shank should be selected so that its ends are flush, i.e. did not protrude from the spindle.