Assembly diagram of the product. Drawing up technological schemes of assembly with a base part
The design documentation for any electrical equipment must include a wiring diagram. Let's consider how important this drawing is, that it allows the personnel servicing or operating the equipment to understand, that is, its direct purpose. Let's get acquainted with examples and the principle of construction.
Purpose
Let's start with the basics. For maintenance, repair, installation or adjustment of equipment, it is necessary to understand both the algorithm of its operation and the principle of operation. For this purpose, the accompanying product documentation includes diagrams, which are drawings that display the symbols of the components and components of the device, as well as the relationships existing between them.
The construction of schemes is carried out according to the ESKD standards, which are regulated by the corresponding GOST. These drawings are in demand at the stage of design, production, as well as during the operation of the equipment. Depending on the purpose, electrical circuits are usually classified by type. They are:
- Structural. Used to determine the main functional units of the device, display the existing relationships between them and for general purposes.
- functional. They contain a description of the processes occurring in the sections of the chain. At the development stage, it is possible to compile an analytical model of the device, which gives an idea of its functional purpose of a particular node. During operation, on the basis of such a scheme, the behavior of the equipment is justified, which greatly facilitates diagnostics, debugging and repair.
- Fundamental. They display the element base and the relationship of all components to each other. It is the circuit diagrams that are the basic basis for the process of developing electrical equipment. An example of such a circuit is shown below.
- Mounting. Specify the geometric position of all components of the node, and also display the connections between them, made by connecting elements. On the basis of schemes of this type, electrical equipment or its components are assembled. The figure below shows an example of a wiring diagram for starting an engine controlled by a reversible magnetic starter, which allows you to visualize the connection of a push-button post.
- Wiring diagrams, showing the connection of external devices.
- Location maps, unlike mounting ones, show only the position of the node elements without displaying links.
- General, this type of diagrams allows you to get a visual representation of the nodes and relationships between all elements, which makes it easier to understand the structure of a complex object.
To summarize, without the schemes listed above, it is not only impossible to create high-quality and reliable equipment, but it is also difficult to organize its qualified maintenance.
The procedure for developing a wiring diagram
There are several ways to develop circuits of this type, the choice of one or another of them depends both on the type of installation of elements and the functional purpose of the equipment. For example, address marking is used to describe the switching of a secondary circuit. Since this method is the most common, we will describe the procedure for its development.
First of all, the contour of the device is applied to the drawing, into which the elements used in the equipment are inscribed, for example, terminal blocks or rails with clamps. In this case, the scale may not be observed. At the top of the drawing (above the contour) the view is indicated, in the example below it is the inscription "Rear wall of the box".
Each element involved in the scheme receives a unique address. To display it, a circle is drawn (whose diameter is from 10 to 12 mm.), Divided horizontally in half. The component number is entered in the upper part of the divided circle, and the symbol in the lower part, in accordance with the element diagram. For example, for a terminal block consisting of 10 clamps, in the wiring diagram, each of them can be assigned a unique address.
Note that the elements that switch power circuits are assigned only a symbol, that is, without a component number.
The development of the scheme begins with the preparation of a blank, according to the rules described above. When it is ready, proceed to the designation of connections, while using addresses, not lines. This marking principle makes it easy to determine the direction of the wires, which greatly simplifies the installation process.
For a more detailed explanation of the principle of constructing wiring diagrams, consider a few examples.
Example: wiring diagram for a 1 room apartment.
The figure below shows a typical electrical wiring diagram. Looking at the graphic image, it becomes clear that it includes two branches. The first provides electricity to the hall and hallway, the second is for the bathroom, kitchen and bathroom. At the same time, both lines simultaneously feed both lighting and sockets for connecting electrical appliances.
Of course, such a connection principle is irrational, since in the event of a short circuit, the room will be completely de-energized. In addition, if it is planned to install such powerful consumers of electricity as an air conditioner, boiler or electric furnace, it is advisable to conduct a separate power line for each of them.
This diagram is provided as an example to clearly show how, having a graphic image of the project in front of you, determine its weaknesses.
An example of a wiring diagram for a warm water floor in an apartment.
The connection diagram can be used not only for electrical equipment, as can be seen from the figure below, it perfectly reflects the structure of a warm floor connected to the central heating circuit.
Legend:
- 1 - ball valve installed on the supply line;
- 2 - ball valve, at the outlet;
- 3 - cleaning filter;
- 4 - valve to the return line;
- 5 - three-way mixing valves;
- 6 - valve for restart;
- 7 - a pump that circulates the working fluid;
- 8 - a valve blocking the return manifold;
- 9 - shutoff valves blocking the entrance to the supply manifold;
- 10 - housing of the return collector;
- 11 - supply manifold;
- 12 - ball-type shut-off valves blocking the return;
- 13 - valves for shutting off the supply;
- 14 - valve for bleeding air;
- 15 - drainage valves;
- 16 - central heating battery.
This scheme is given as an example; such an organization should not be taken as a reference. If you want to make a water heated floor according to this principle, then first of all you need to coordinate your project with a company that provides central heating services.
And in conclusion, we will give an example of a well-designed wiring diagram of a heating system based on a convector with a thermostat.
To understand the circuits, it is necessary to know the conditional graphic images of the components, their alphanumeric designations. Understanding the principle of operation and the algorithm of the elements will significantly contribute to the assembly process and debugging. As a justification for such requirements, we will give as an example the wiring diagram of the base board of a shortwave transceiver.
As can be seen from the figure, an explanation is attached to the diagram, which contains the information necessary for installation. But it will be clearly not enough in the absence of basic knowledge, as a result, you can make a mistake with the polarity of electrolytic capacitors or diodes, and the assembled device will not function.
For the sake of justice, it should be noted that a specialist can also make such an oversight, which is why it is customary to apply the arrangement of elements and indicate their polarity on industrial circuit boards (see Fig. 9). This significantly reduces the chance of assembly errors.
Modern electrical equipment in its work uses numerous technological processes that proceed according to various algorithms. An employee involved in its operation, maintenance, installation, adjustment and repair must have reliable information about all their features.
Providing ongoing events in a graphical form with the designation of each element in a certain, standard way, greatly facilitates this process, allows you to transfer the ideas of developers to other specialists in an understandable form.
Purpose
Electrical circuits are created for electricians of all specialties, have different design features. Among the methods of their classification, division into:
fundamental;
mounting.
Both types of schemes are interconnected. They complement each other's information, are performed according to uniform standards that are understandable to all users, and have differences in purpose:
circuit diagrams are created to show the principles of operation and interaction of the constituent elements in the order of their operation. They demonstrate the logic inherent in the technology of the applied system;
wiring diagrams are made as drawings or sketches of parts of electrical equipment, according to which the assembly and installation of the electrical installation is carried out. They take into account the location, layout of the components and display all the electrical connections between them.
Wiring diagrams are created on the basis of the circuit diagrams and contain all the necessary information for the installation of an electrical installation, including the implementation of electrical connections. Without their use, it is impossible to create high-quality, reliable and understandable for all specialists electrical connections of modern equipment.
The protection panel shown in the photograph is connected by numerous cables to measuring current and voltage transformers, power executive equipment, hundreds of meters apart. It is possible to assemble it correctly only according to a well-prepared wiring diagram.
How wiring diagrams are created
First, the developer creates a circuit diagram that shows all the elements he uses and how to connect them with wires.
An example of a simple connection of a DC motor to a power circuit using a contactor K, and two buttons Kn1 and Kn2 demonstrates this method.
Powerful power normally open contacts of the contactor 1-2 and 3-4 allow you to control the operation of the electric motor M, and 5-6 is used to create a self-retaining circuit of the A-B winding energized after pressing and releasing the Kn1 "Start" button with a closing contact 1-3.
Button Kn2 "Stop" with its NC contact removes power from the winding of the contactor K.
The positive voltage potential “+” is supplied to the electric motor through the wire marked with the number “1” and “-” - “2”. The rest of the wires are marked with the numbers "5" and "6". The way they are marked may be different, for example, with the addition of letters and symbols.
In this way, all the contacts of the windings, switching devices and connecting wires are shown on the circuit diagram. Other information necessary for the work may also be indicated.
After the circuit diagram is created, a wiring diagram is developed for it. It depicts the elements that are involved in the work. Moreover, both all existing contacts of switching devices, buttons (example Kn1 and Kn2), contactors and relays, and only those used in the case under consideration (example of contactor K) can be shown to simplify perception.
All mounting units are numbered with an individual number assigned to each position. For example, our diagram shows:
01 - terminal block for connecting power circuits;
02 - motor contacts;
03 - contactor;
04 - button "Start";
05 - Stop button.
The contacts of buttons, relays, starters and all electrical elements of the circuit are numbered on the body of each device or indicated by a specific position in the technical documentation.
Images of wires are made with straight lines and marked in the same way as in the circuit diagram. In the considered version, they were assigned numbers 1, 2, 5, 6.
During the assembly of complex circuits, it is convenient to work immediately with wiring and circuit diagrams. They supplement general information that can be difficult to keep in memory.
At the same time, it should be understood that the ideas depicted on paper should be implemented on real equipment and just as well, clearly read, and be informative. For this purpose, any element is signed, marked, marked.
Designations of devices and devices
On the front side of the panels, control cabinets, inscriptions are made explaining to the operational personnel the purpose of each electrical device, and for switching devices - the position of the switching element corresponding to each mode.
Keys and buttons are signed according to the action, for example, "Start", "Stop", "Test". The signal lights indicate the nature of the acting signal, for example, "Blinker not up".
On the reverse side of the panel, against each element, there is a sticker (usually round) with a fraction indicating the mounting position according to the diagram above and a short designation according to the installation diagram below, for example, 019 / HL3 - for an alarm lamp.
Wire designations
When installing equipment, each end of the wire is put on tubing signed with light-resistant and indelible ink, indicating the accepted marking. They are connected to the indicated terminals. When only the numbers "0", "9" are found in the designation. “6”, then after them they put a dot, excluding the incorrect reading of the information when considering the inscription on the reverse side.
For simple equipment, this technique is sufficient.
On complex and branched systems add the return address of the end. It consists of two parts:
1. first, the numbering of the reference designation of the element connected on the reverse side is numbered;
For example, on terminal 2 of the Kn2 button, a wire with a cambric, signed 5-04-3, must be connected. This inscription is deciphered:
5 - wire marking according to the assembly and circuit diagram;
04 - the number of the mounting unit of the "Start" button;
3 - terminal No. Kn1.
The alternation sequence, as well as the use of brackets or other designation separators, may vary, but it is important to do it the same way in all sections of the electrical installation. Marking must be carried out in strict accordance with the working drawings and wiring diagram.
For information: earlier, the marking of the ends of the wires was performed:
putting on porcelain tips with the application of symbols with oil paints;
hanging aluminum tokens with minted information;
fixing cardboard tags with ink or pencil inscriptions;
in other available ways.
The wiring diagram can supplement or replace the wire connection table. She points out:
marking of each wire;
the beginning of its connection;
reverse end;
brand, type of metal, cross-sectional area;
other information.
Cable designations
A mandatory element of each electrical installation is a cable magazine created for each individual connection in complex areas or one common for several simple ones. It contains complete information about each cable connection.
For example, with sectioned power buses and switches that control the operation of 25 overhead power lines, a mounting connection is created for each overhead line. It is assigned an individual number, which is indicated in the documentation and on the equipment.
Line No. 19 from this outdoor switchgear is given an operational dispatching name for the main settlement of power supply and an installation designation, for example, 19-SL, which is affixed to all equipment, including the secondary cable networks of this overhead line at the substation.
In addition to the cable belonging to the line, in the cable magazine and on the equipment, its attribute is indicated by purpose, for example:
alarms;
blocking;
other secondary devices.
measuring circuits of current or voltage;
automation or control scheme;
When installing electrical circuits, cable lines of various lengths can be used. At the entrance to the panel or cabinet, their number can be quite large. All of them are marked at both ends, as well as at the transitions through the walls of the building and other building structures.
A tag is hung on the cable with information indicating its belonging, purpose, brand, composition of cores. When cutting it, each wire is marked. On the tips connected to the electrical circuit, information about the cable accessory, the number of the switched terminal on the terminal block and the designation of the chain is applied.
Free cable cores that are in reserve, as well as workers, must be called and marked. However, in practice this requirement is rarely implemented.
Features of the designation of individual elements on wiring diagrams
According to local conditions, they sometimes deviate from generally accepted rules, facilitate the drawing of diagrams and the installation of electrical circuits without compromising their reading from nature.
Most often this manifests itself when:
hinged mounting of parts directly on the contact outputs of relays and devices;
installation of short, clearly visible jumpers.
Hanging mounting
An example of installing diodes VD4 and VD5 in parallel with the terminals of the A-B windings of relays K3 and K4 is shown in a fragment of the wiring diagram.
In this situation, they are mounted directly, without marking and signatures.
Jumpers
The same fragment shows the installation of a jumper between the terminals of the same name A of the windings of the same relays.
The installation of electrical equipment is carried out according to the principle and wiring diagrams, created according to uniform rules. It must meet the requirements of visibility, accessibility, information content so that repairs and maintenance work are carried out quickly and efficiently.
The assembly diagram is a graphical representation of the composition and the sequence of connecting the elements and parts of the product in the form of symbols (Fig. 3). The diagram facilitates the development of a route technical process, giving a clear, visible idea of the product assembly sequence. The diagram shows all the parts, assembly units and basic materials included in the device. The scheme of the assembly composition is shown in the form of steps corresponding to the stages of assembly according to the principle "from simple to complex".
The selected rational assembly route is graphically designed as a flow chart with a base part. The scheme itself is presented in the graphic part of the course project.
The technological scheme of assembly with the base part shows in what sequence and by what processes it is necessary to attach to each other and fix the elements included in the product during its assembly. The stator with cover pos.2 was chosen as the base part
5. Technological assembly process um.
Check by external inspection the parts and assemblies entering the assembly at a magnification of 6-9 times for the absence of dirt, burrs, scuffs, sharp edges and mechanical damage. Check the availability of accompanying documentation for parts and assemblies.
Interoperational storage of parts: the stator, the cover with the stator, the housing and the rotor, as well as the assembled device, should be carried out in desiccators with an indicator desiccant.
Ultrasonic wash all fully machined parts, except for the stator with cover.
Re-preserve the sh / p according to the instructions specified in the technical specifications for ball bearings.
Store the sh/n parts at the workplace according to the instructions specified in the specifications for ball bearings.
Select pairs of ball bearings in terms of stiffness so that in terms of the displacement of the outer ring relative to the inner ring in the axial direction under a load of 1 kg, they do not differ from each other by more than 0.0005 mm.
In the socket of the cover, position 2, ensure the fit of the outer ring of the w/n with a force of 0.2 ... 1 kg. Before checking the seating force, the outer ring of the s/n must be installed in the seat of the cover so that the outer end of the ring coincides with the plane of the end of the cover.
Fasten the housing with the cover with 6 screws through the washers.
Install the screw pos.6 beforehand.
Fasten the flange pos.5 with 6 screws.
On the necks of the rotor pos. 1, ensuring a fit with a force of 5 ... 10 kg, press on the inner rings of the s/n. On the seating surfaces of the rotor, traces from the landing of ball bearings are allowed in the form of scratches with a purity of at least 7.
Install the nuts pos. 9 on the rotor necks and crimp them on the rotor Ø 3.5 into the groove.
Perform dynamic balancing of the rotor.
Preparatory.
Flushing.
Locksmith.
Control.
Assembly.
Assembly.
Assembly
Adjusting.
The centers of drilled holes (with a diameter and depth up to 2 mm) should be located at a distance of 2÷3 mm from the end face of the ring made of VNZh7-3 alloy (balancing plane).
Check dynamic balancing.
Wipe the rotor assembly with the inner rings of the s/n from grease, metal dust and other contaminants.
Control.
Permissible unbalance 0.01 gcm 2 .
In the socket of the housing, position 3, ensure the fit of the outer ring of the w/n with a force of 0.2 ... 1 kg. Before checking the seating force, the outer ring of the s/n must be installed in the seat of the housing so that the outer end of the ring coincides with the plane of the housing sleeve.
Control the fit of the outer ring of the s/n until it stops in the seat of the body pos.3 by sending it under an axial load of 15 kg. The case pos.3 is suitable for assembly if a force of 15 kg causes a relative movement of the microcator needle during 3-fold measurement by no more than 0.0004 mm.
Assembly.
Control.
If there is a greater displacement, it is allowed to remove the ring, additional grinding of the socket and re-measurement. Checking the delivery of the w / w to the body is carried out before each assembly.
Assemble the stator ball bearing with cover and housing according to the specifications for the ball bearing.
Lubricate ball bearings with grease VNII NP-228B OST 38 01438-87 at a dose of 20 ± 2 mg.
To ensure the non-parallelism of the body plate, pos. 3 with respect to the cover pos. 2 within the limits indicated on the drawing, it is allowed to finish the plastic before technological tests while maintaining the cleanliness and geometric shape of the surface.
Install clamp pos.4
Set the axial preload w / n. The value of the axial preload of the ball bearings is set according to the elastic deformation of the bottom (membrane) of the instrument housing. To determine the magnitude of elastic deformation of the membrane of the instrument housing, it is necessary to apply an axial load P to the membrane, the value of which is equal to the axial interference of the ball bearings according to the technical requirements for the instrument.
Tighten the screw pos.6 finally.
Lock the screw pos.6 through the flange pos.5 with clamps pos. 4.
Control.
Check axial tension.
Screws 7,8,11 put on enamel EP-275.
In two diametrically located slots of the screw pos. 6 and on the cylindrical surface of the part pos. 5 opposite the slots of the screw pos. 6 apply enamel EP-275.
Dry the device at a temperature of +80°C - 1.5 ÷ 2 hours.
Carry out technological tests according to specifications.
Put the device in a container.
Hand over to the warehouse of finished products.
Assembly.
Assembly.
Adjusting.
Assembly.
Thermal.
Control.
Transfer.
To determine the sequence of assembly of the product and its components, technological assembly schemes are developed. The assembly units of the product, depending on their design, can consist either of individual parts, or of assemblies and subassemblies and parts. There are subassemblies of the first, second and higher stages. The subassembly of the first stage is included directly in the composition of the node; the subassembly of the second stage is part of the first, etc. The subassembly of the last stage consists of only individual parts.
Technological schemes are compiled separately for the general assembly of the product and for the nodal assembly of each of its nodes (subassemblies). Consider the principle of drawing up technological assembly schemes. Fig. 20.1 shows an assembly unit with a worm wheel, and Fig. 20.2 shows the technological scheme of its assembly.
Fig.20.1 Assembly unit - shaft with worm wheel
Technological schemes are the first stage in the development of the assembly process. Schemes in a visual form reflect the assembly route of the product and its components. Technological assembly diagrams are based on assembly drawings of the product.
On the technological schemes, each element of the assembly is indicated by a rectangle divided into three parts. The upper part of the rectangle indicates the name of the part or assembly unit (assembly or subassembly), in the lower left part - the number assigned to the part or assembly unit in the assembly drawings of the product, in the lower right part - the number of elements to be assembled. Assembly units are denoted by the letters "Sb" (assembly). Base parts are called parts or assembly units from which the assembly begins. Each assembly unit is assigned the number of its base part. For example, “Sb.14” is an assembly unit with base part 14 (wheel hub).
On the left side of the diagram (Fig. 20.2) indicate the base part or base assembly unit. On the right side of the diagram indicate the assembled product assembly. These two rectangles are connected by a horizontal line. Above this line, rectangles indicate all parts that are directly included in the product, in the order corresponding to the assembly sequence. Below this line, rectangles indicate assembly units that are directly included in the product.
Schemes for assembling assembly units can be built both separately and directly on the general scheme, developing it at the bottom of the scheme.
The corresponding stage of the node is indicated by digital indices before the letter designation "Sat." For example, if in the designation the assembly has the index "1Sb.7", which means the first stage assembly with base part No. 7.
Technological assembly diagrams are accompanied by captions if they are not obvious from the diagram itself, for example, “Press”, “Weld”, “Check for runout”, etc.
Technological schemes for assembling the same product are multivariate. The optimal option is chosen from the condition of ensuring a given assembly quality, economy and productivity of the process at a given scale of product output. . The design of the product must allow the possibility of its assembly from pre-assembled units. The nodal composition of the product can be determined by analyzing the assembly drawing, mentally disassembling the product. Knots in the process of disassembly can be "removed" entirely.
Drawing up technological schemes is advisable when designing assembly processes for any type of production. Technological schemes simplify the development of assembly processes and facilitate the assessment of the product for manufacturability.
Practical work No. 1
Development of a technological scheme for disassembly and assembly of CE
Goal of the work
1. To study the concepts of the technology of disassembly and assembly of assembly units.
2. Learn to develop a technological scheme for disassembling and assembling the CE and arrange it in the form of a technological scheme.
Initial data
The initial data for the development of the technological scheme of assembly (disassembly) are:
Assembly drawing of the product with specification;
Specifications for assembly (disassembly) indicating fits of mating parts, test modes of the product, technological instructions for selection of parts, assembly, control and adjustment of interfaces or CE;
Repair program.
In addition to the documentation, it is desirable to have a sample of the product, on which it would be possible to perform trial disassembly or assembly according to the developed technological scheme.
1. Examine the assembly drawing and the assembly specifications attached to it.
2. Development of a structural-technological scheme for dismantling CE.
The development of CE as a whole is carried out in a certain sequence, which is determined by the design of the product, as well as the program of the repair enterprise and its homogeneity in relation to the types and brands of machines being repaired.
When developing a disassembly scheme, the task is to divide a given node into constituent elements in such a way that disassembly can be carried out
the largest number of these elements independently of one another (in parallel).
Such a division makes it possible, when organizing repair work, to reasonably assign certain repair work to specific performers.
The disassembly scheme is built so that the corresponding assembly units are presented in it in the order in which it is possible to remove these elements when disassembling the assembly. CE and parts are depicted in the diagram in the form of rectangles indicating the index, name and number of elements. For greater clarity, a rectangle depicting an assembly unit can be distinguished by marking its outline with a double line (Fig. 1).
In the diagram, the rectangles characterizing the assembly units are recommended to be placed on the left, and the details on the right along the line.
The beginning of the disassembly is the assembly unit, and the end is the base part. For example, consider the input shaft of a car gearbox (Fig. 2).
Figure 2. Vehicle gearbox input shaft assembly
1 - input shaft; 2 - nut; 3 - retaining ring; 4 - ball bearing
radial single row; 5 - retaining ring; 6 - roller 8x20.
The report gives a brief description of the disassembly. Disassembly of the node in question is carried out in the following sequence:
Unscrew the ball bearing nut 2, remove the circlip 3, remove the ball bearing 4, remove the circlip 5 and remove the rollers from the roller bearing 6.
An example of a disassembly flow chart is shown in Figure 3.
The number of jobs is determined by the program of a particular repair company and the complexity of performing the listed operations.
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Fig.3. Technological scheme of disassembly of the primary shaft assembly
Disassembly must be carried out in the strict sequence provided for by the technological regulations. The basic techniques and principles of disassembly are as follows:
Assembly units are disassembled directly at the place of general disassembly, as well as at the places of their repair and assembly in accordance with the technological scheme.
First, remove parts that can be easily damaged (injection tubes, rods, levers, rods, etc.). Then, separate assembly units are dismantled, which are disassembled at other workplaces.
When removing large parts fixed with a large number of bolts, in order to avoid the appearance of cracks, all bolts and nuts are first released half a turn and only after that they are unscrewed.
Rusted connections are moistened with kerosene before unscrewing.
After disassembly, fasteners are placed in mesh baskets for subsequent washing. It is not allowed to use a chisel and a hammer to loosen bolts, nuts, fittings, etc., as this may damage them. Shaped nuts and fittings are unscrewed with special keys.
Pressed parts are removed under pressure or with the help of pullers and fixtures. In some cases, fittings, bushings and axles can be pressed out with special punches with copper tips and hammers with copper bikes.
When the bearing is pressed out of the housing, the force is applied to the outer ring, and from the shaft to the inner one. It is forbidden to use a percussion instrument.
It is advisable to place the removed parts on racks and devices for transportation to the sink, so as not to damage the work surfaces.
It is impossible to disassemble parts that are processed as an assembly during manufacture (caps of main bearings with blocks, etc.). In addition, it is forbidden to remove parts subject to joint balancing, as well as run-in pairs of parts suitable for further work (bevel gears of the final drive, gears of oil pumps, etc.). Parts that are not subject to maintenance are marked, tied with wire - re-connected with bolts and placed in a separate container or kept complete in other ways.
3. Construction of a technological scheme for the assembly of CE.
The assembly flow diagram, as well as the disassembly flow diagram, is an auxiliary technological document (not included in the number of mandatory technical documentation documents, which graphically shows:
The sequence of connection of parts and assembly units included in the product;
The composition of the assembly units included in the product;
Performing operations not related to the attachment of parts and assembly units (control, adjustment, filling of oil or working fluids, painting, packaging, etc.)
The technological scheme of assembly is intended for:
Disclosure of the structure of the product and the possibility of using a nodal assembly;
Formalization and algorithmization of the development of the assembly process;
Evaluation of product design from a technological point of view.
For the design of the assembly process, the most acceptable form of the assembly flow chart is the scheme that provides the ranking of assembly units by levels and orders. When compiling such a technological assembly scheme, a number of formalization descriptions and designations are also used.
1. Assembly units (CE) included in the product have different orders, ranging from 0 to N. SEO - assembly unit of zero order, is
items that do not require assembly, These include parts, bearings, products that come to the assembly from the side (purchased or assembled in other departments).
2. The order of an assembly unit is always one more than the maximum order of its constituent elements.
When determining the order of an assembly unit, consider the following:
When connecting any next part to an assembly unit, the order of the assembly unit does not increase (Fig. 4a, b).
The assembly unit moves to the next level only after the assembly units of the same order are connected (Fig. 4c).
The rules for determining the order of assembly units in general can be written as:
Fig 4. Scheme of formation of the order of assembly units
To describe assembly units in a ranked technological assembly scheme, a rectangle is used, shown in Fig. 1.
3. The following formalization designations for actions related to the assembly of product elements are used in the assembly flow chart:
Attaching an assembly unit (Fig. 5a) is indicated by an arrow at a given assembly level with transition numbering;
Attaching an assembly unit with additional actions (Fig. 56);
Actions not related to attaching an assembly unit and providing for adjustment, measurement, testing, filling with working means, balancing, painting, packaging and others (Fig. 5c);
Intermediate disassembly when using adjustment with a fixed compensator (Fig. 5d).
General assembly line 7 8 9
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Rice. 6. Technological scheme of the assembly of the shaft of the primary gearbox
4. Drawing up a list of transitions of the nodal and general assembly.
The list of transitions must begin with the listing of transitions of the general assembly.
The list of transitions of the nodal assembly is expressed in the enumeration of assembly transitions in the sequence of installation of assembly units of the corresponding order on the general assembly with their disclosure up to the first order CE. 7.
Rice. 7. Structural diagram of compiling a list of transitions of the nodal and general assembly
General Assembly
1. _____________________________
2. _____________________________
Assembly CE2
Assembly CE11.
1. __________________________________________
2.______________________________________
Assembly CE12.
1.__________________________________________
2.______________________________________
The description of the route assembly technology is considered on the example of the primary gearbox shaft assembly technology.
General Assembly
1. Install the input shaft.
2. Lubricate the hole along the rollers with grease.
3. Install rollers.
4. Install retaining ring 5.
6. Install retaining ring.
7. Screw on and tighten the nut.
8. Punching the retaining ring.