Screwing in screw piles with your own hands. How to tighten screw piles with a drill? Technological aspects of the screwing process
Construction has always been and remains a responsible business. The durability of the structure depends on the quality of work. The foundation is considered an important part of any building. In modern construction, screw piles are often used. This technology helps to significantly reduce financial costs and construction time.
Screw piles are screwed into the ground using special equipment, but few people know that this can be done with their own hands. The article describes in detail how to install piles manually. But before considering the installation process, let's learn more about this modern technology.
Application
Screw piles are used as supports in difficult soil: uneven terrain, swampy or frozen soils. Initially, the technology came from military craft, where it was necessary to quickly build and dismantle special-purpose objects. Now this method is actively used in civil engineering.
Used for the construction of the following structures:
- frame and modular buildings, low-rise buildings;
- light structures, fences, advertising boards;
- supports for high-voltage lines and pipelines;
- bridges, piers.
Installation is carried out hydraulically or manually. The piles are screwed into the ground like a self-tapping screw. If the soil is very frozen, a leader well is made. Their calculated load-bearing capacity depends on the correct installation of supports.
Advantages and disadvantages of a screw foundation
- are erected faster than a concrete foundation;
- used in swampy, unstable and icy soils;
- ready for full load after screwing;
- can be installed at any time of the year;
- no need to level the landscape;
- are cheaper than concrete foundations.
Flaws
- limited service life;
- cannot be used on rocky ground;
- It is difficult to make good anti-corrosion protection.
This is hard work, so small diameter piles are used because they are easier to screw in. Screwing in the supports manually occurs in order to save money or when it cannot be done by machine. The manual method allows you to build small buildings, for example, a bathhouse, a gazebo or a fence. To work, you will need simple tools and several assistants.
Possible obstacles
Manual installation becomes more difficult if there is a lot of debris or stones in the ground. Make sure that it does not contain large objects: crushed stone, iron, bricks, etc. Small fragments will not cause any harm, but large stones will cause the support axis to deviate or the blades will be bent.
Sometimes there are concrete blocks or slabs in the ground, which cannot be removed without seriously digging up the area. This problem can stop the entire installation process or make significant adjustments to the foundation layout.
Try to find an area where there are no thickets within a radius of 20 m. The root system, especially of large trees, is well developed. Even a rotten stump located nearby will significantly complicate the screwing of piles.
To manually screw in the pile, it is necessary to use long levers. If there is a building, fence or pole next to the planned construction, they will interfere with the installation of supports.
Preparatory work
- Installation of screw supports begins with searching and inspecting the construction site. Examine the soil carefully. The choice of piles of a certain diameter depends on its condition. It is difficult to screw in large supports in soil that is too dry or clayey.
- Having chosen suitable piles, calculate how many pieces you will need for the work. The distance between them during installation depends on their number.
- To ensure that screw piles serve properly for many decades, anti-corrosion treatment is performed. Apply several layers of protective coating.
There are several processing options:
- primer for metal – standard coating;
- bitumen mastic – protects the surface of the pile from contact with moisture;
- cold galvanizing - zinc, interacting with the metal surface of the pile, creates a weak electric current that prevents corrosion;
- cold galvanizing and bitumen mastic - combined processing;
- cold galvanizing, bitumen mastic and polymer film - the first two layers of protection are covered with shrink film, this provides maximum protection.
Tools for installing screw piles
- Shovel - for leveling screwing points.
- Magnetic level - will help control the position of the pile.
- Drill – should be smaller in diameter than screw piles.
- Tape measure – necessary for taking measurements.
- Hydraulic level – used to set horizontal marks.
- A crowbar and two pipes 2 m long - these will make levers.
- Hammer – will be needed to hammer in the peg.
- Grinder – for cutting piles.
- Thin rope - for marking the foundation.
- Knife, gloves, pencil.
Foundation marking
Accuracy and accuracy in calculations is required. To work you will need rope and pegs. If the foundation is rectangular, first determine the corner support points. Hammer the pegs and connect them with rope. Try to make the rectangle shape even. On each side, determine equidistant points for the remaining piles. Once all the marks have been placed, you can begin installing the supports.
Screw pile installation technique
The supports must be installed in the corners first. To do this, drill guide holes. The depth should be equal to 1/3 of the length of the pile, and the size should be less than the diameter of the pile. Once you begin the installation process, try to control the evenness of the vertical position of the support. A magnetic level will help you.
The piles are screwed in using levers, in our case this is an ordinary crowbar. When the twisting becomes tight, the arms are extended with additional pipes. This process must take place evenly and on command so as not to displace the support.
If the pile stops turning, this means that you have reached a layer of soil whose density is sufficient to support the weight of the structure. In this case, you should not continue screwing. After the corner piles are installed, connect them with rope at the bottom and top. This will help align the remaining supports evenly – vertically and heightwise.
When the foundation is ready around the perimeter, place marks inside. To do this, columns of parallel sides are connected with a rope. At the crossing points, it is necessary to drill holes for the installation of internal foundation piles.
The manual method does not allow for smooth installation. Even if you screw in smoothly and slowly, the support will gradually move to the side. Therefore, it is periodically necessary to check the degree of deviation with a magnetic level. If the displacement is significant, then move the pile until it is level and make several turns.
The displacement is affected by stones stored in the ground. In this case, it is difficult to align the supports. There are two solutions: first, rotate the pile deeper than the stone and loosen it so that it can be placed evenly and make several turns. Second, pull out the support, use a drill to go through a difficult section of soil, and then continue installation.
Trimming
Not all piles can be screwed in to the required level. Therefore, they are shortened with a grinder, leveling them in height. It is recommended to trim below the arm insert hole. It is convenient to draw marks using a hydraulic level - a long, thin hose filled with water and working on the principle of communicating vessels.
Concreting
After trimming, the screw piles are filled with a mixture of concrete and sand. The solution should not be too thick or liquid. This procedure makes the supports stronger and more resistant to stress. Some builders add reinforcement to the pipe to provide additional rigidity.
Concrete protects the inner surface from oxygen and moisture and extends the life of the foundation. If the installation of piles takes place in the cold season, winter additives are added to the solution. They will make concrete resistant to low temperatures.
When the solution dries, the pipe is sealed with caps for subsequent piping. Welding seams are treated with an anti-corrosion agent.
Screw piles are a practical technology for the construction of any structures. Inexpensive cost and fast installation speed have made this type of foundation in demand. Screw pile technology is now available to everyone. You can apply it yourself or use the services of construction companies.
Video: tightening screw piles with your own hands
This article is for those who have decided to independently install a foundation on screw piles, so it will be more like a practical guide, where I not only share my accumulated experience, but also give detailed recommendations for action.
Soil is a very sensitive issue for many land owners and, perhaps, the most important one. True, in my practice there have never been cases when it was impossible to tighten screw piles - it always worked. But sometimes foreign objects (most often stones) that appeared on the way of screwing in the pile still made their own adjustments to the pile field - some piles went out of line. No one is immune from this - there is a factor of uncertainty in any business. For screw piles, such factors are stones, tree roots and other unidentified objects that are located underground. A header is capable of correcting the location of a pile that has fallen out of order - its platform compensates for the departure from the center of the line and will allow, at least partially, to capture the frame for the future structure.
The success of screwing depends on the soil, information about which can be obtained by test drilling (or screwing). The owner’s knowledge, as a rule, is limited to information about the presence of stones on the site and their locations. When there are a lot of stones, then most likely it will not be possible to install a pile foundation. If you come across stones periodically - not in continuous deposits - then you can try to install piles and, most likely, the result will be successful. In general, all types of soils, except rocky ones, are suitable for screw piles.
Determining the composition of the soil by drilling, in my opinion, is much more effective than the screwing method because when drilling we see and feel the soil, we can make markings and prepare holes of smaller diameter, so that we can then quickly tighten the piles according to the existing markings. And screwing is a “chance” check - whether the pile will work or not. In addition, you will most likely have to purchase a used pile from a contractor for these purposes. This method is unprofitable and ineffective. Only drilling or a simple soil analysis will help determine by 90% whether it is possible to screw the piles. So, if screw piles are suitable for your site, then move on to choosing the piles themselves...
Selecting the diameter and length of the pile
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Today, the diameter of screw piles from different manufacturers varies from 47 to 108 mm; there are piles with a larger diameter, but this is on special order. Small diameter piles: from 47 to 76 mm, are mainly used in the construction of fences or fortifications. An 89 mm pile can be used in the construction of frame houses or light structures. But these piles, most often, are used as auxiliary ones.
Let's focus our attention on the 108 mm screw pile. It can withstand loads of up to 3500 kg! This means that on such a foundation you can build all types of houses, except stone ones, and have no doubt about its strength - the foundation will serve faithfully for many years. You only need to correctly calculate the number of piles. This is not difficult to do. It is necessary that the bearing capacity of the foundation has a safety margin of 30% of the weight of the structure, taking into account additional loads. The length of the pile can also be taken with a reserve, because it is easier to cut it than to weld an additional pipe to the pile, but you should still count on at least the fact that the pile will go at least to the depth of soil freezing - 1.5 m. The most popular piles 2 –2.5 m. After you have calculated everything, order screw piles from the manufacturer and take them to your site.
Screwing tools
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The tool plays an important role in the process of screwing screw piles. One might even say dominant, since the final result directly depends on it. Here is a simple set of tools without “special tools” that can be easily assembled at hardware stores. So:
- shovel - useful for leveling the surface under the place where the pile is screwed;
Level 30 cm, on a magnet - attached directly to the pile during screwing to control the vertical level;
A hydraulic level of at least 15 m is necessary for setting a horizontal mark;
A tape measure of at least 20 m is used to take measurements;
Nine rods of A12 reinforcement, 1 m each, are used to mark the pile field; twine is wound around the entire perimeter of them. As an alternative to reinforcement, you can also use ordinary pegs, but then they should be as even as possible;
A metal scrap is threaded through a pile, and pipe-levers are strung on it;
Two pipes with a diameter of 50 mm, 2.5 m each, are put on the scrap on both sides and serve as levers for screwing in the pile;
Hammer or small sledgehammer - useful for driving reinforcement or pegs into the ground;
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- garden drill - the drill must have a diameter smaller than the piles you will be screwing. Its role in the screwing process is to drill guide holes or probe the soil under the pile field. The depth of the hole must be an order of magnitude shorter so that the screw pile can independently travel a certain path and become compacted in the ground;
- twine 180 m long - serves for marking, and also as beacons for visual control of the displacement of screw piles (if it remains, it will never be superfluous);
Grinder and cutting wheels - for cutting screw piles at one level;
Extension;
A special marker or a construction pencil - one of two things. They will be useful for making marks;
A sheet of thin cardboard is necessary for “outlining” an even circle on a screw pile when the process has come to leveling at one level. The pile is cut at this mark. To make the line even, you need to wrap the pile with a sheet of cardboard and align the ends at the mark, then draw an even circle;
Travel knife - useful for cutting twine, etc.;
Gloves - so you don't have to work with bare hands.
Two workers are required to screw the piles. The ideal option is two installers and one more person who will control from the side the vertical level of the screw pile, row line, etc.
Since piles most often have to be cut, you cannot do without electricity, and if you don’t have it, you will need a generator.
Making the markings
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The markings are done meticulously, down to the millimeter. It uses reinforcement and twine. In most cases, the foundation is shaped like a square or rectangle. If you have the same one, then first you will need to set the outer perimeter and screw the piles into the four corners - it is from them that the entire foundation is built. We take a tape measure, a drawing, eight bars of reinforcement (two for each corner), twine and get started...
The first thing we need is a reference to the site, or the so-called “starting point”. Therefore, it is necessary to draw the first line of any side of the foundation; it must be unshakable, because the geometry of the entire foundation is built from it (all other sides can be moved to set the desired size). We measure so that this side is parallel to the fence, road, etc., and stretch the twine, tying it to two reinforcements driven into the ground. The marking line should be stretched so that it is longer than the future foundation. In general, each subsequent line of the foundation is taken out of its dimensions, as a result, all marking angles are criss-crossed. This is necessary so that the reinforcement does not interfere, and the “flexible” angles obtained with the help of twine can control the screwing of the pile. See Photo 2.
Drilling holes
The holes are drilled with any drill: a garden drill, a homemade drill, a motor drill, but the holes must have a smaller diameter than the pile. This is necessary in order to direct the pile along the trajectory we need, to give it a direction of movement. The depth can be any, but it must be slightly shorter than the pile itself. When twisting a pile without “guides” it is difficult to achieve the accuracy of its required location. In some cases, without a “guide” the pile does not go into the ground at all (going either to the left or to the right). You can try both options and see for yourself. You need to drill holes in the center of the corner so that when you place the pile, it fits neatly into the corner, without moving away from the twine or squeezing it. As shown in Photo 3. Once you have drilled the first four corners, you can start screwing.
Screwing and aligning
We put the pile in the corner. We attach a magnetic level to it and thread a crowbar through it. To begin with, levers are not needed, since at the initial stage much effort is not required.
We begin screwing and monitor the displacement of the pile to the sides. Throughout the entire process, the pile must be clearly in the corner; this is extremely difficult to achieve - it will move to the side, deviating from the vertical position. I'll tell you how to level it a little later. In the meantime, we need to screw four piles into four corners. As the resistance of the pile to twisting increases, we put on levers. You need to twist with equal effort from all participants.
Uneven impact on the levers will lead to even greater displacement of the pile. When two people are spinning, one is constantly looking at the vertical level in order, if necessary, to immediately make adjustments to the work process.
If the soil is passable, you can immediately set four piles at the hydraulic level, this will allow you to subsequently control all the lines and align the remaining piles at this level. After you have screwed in the first four piles, remove the markings and wrap the twine around the piles themselves, because we still need lines to install the remaining piles. If they stand at different heights, then the level can be set using twine and subsequently guided by it. Look at Photo 4.
Please note that all the corner piles are screwed in and level, and there is also twine wound around them, also level, but about 60 cm below the screw piles themselves, so that it is convenient to walk. We need twine in order to further screw in the piles around the perimeter. This is done simply: we take the reinforcement and make transverse markings for the next line of screw piles. We drill holes and fit side piles into the resulting corners. We don’t touch the internal ones for now, we rotate the piles along the entire outer perimeter, then all the internal ones.
The web grows, and we tie twine to each opposite pile. Subsequently, all internal intersections of the twine automatically provide places for screwing in the new screw piles we need. All that remains is to drill and screw. Walking is becoming more and more difficult and you must always be on guard so as not to disrupt or disturb the beacons. This, of course, is not very convenient, but all the inconvenience is more than compensated by the result - all the piles stand together in a row, no matter which way you look at it.
The technique I invented increases the time of work, but allows you to control the displacement of the pile, which cannot be done by relying only on your “diamond eye”. However, I dare to disappoint you - it will never work out perfectly. Still, nuances arise. Look at some moments of screwing in Photos 5, 6, 7. Now let's move on to analyzing and correcting the nuances that arise.
There are nuances
The pile itself will never go straight - it needs to be guided. As soon as you start screwing, the pile begins to shift due to its screw device. It is not difficult to level it and there is only one trick: you need to tilt the top of the pile as much as possible in the direction of displacement and twist it in this position for a certain time, then level it again and see the result. If it falls into place, continue to screw it evenly; if it doesn’t, then tilt it again and continue screwing it at an angle until you achieve the desired result. They also use special devices to forcibly fix the pile and prevent it from moving from the center, but we are considering simple screwing. See what the alignment looks like in Photos 8, 9.
Obstacle on the way
There are several options here and there can be no statistics here, each case is individual. What can be done? Try to pass this place with the screw pile itself using a good force on the levers - with a grinding noise. Sometimes it helps. It happens that even the blades bend, but it’s still worth a try. You can also unscrew the pile back and try to remove the obstacle from the hole. If the obstacle is large, then it can no longer be pulled out. What then? Then, if the pile is not angular and goes more or less deep into the ground, say, a meter, it makes sense to leave it in place. I understand that it did not reach the freezing depth... But if you have driven twenty-one piles, shouldn’t you stop at the last one - the twenty-second? There is still another option: move the foundation. This can be safely done if you encounter similar obstacles even at the stage of driving corner piles. If the corner supports fit well, then you can deal with the rest. This is why corner piles are screwed in first.
The pile may screw in a little and not go any further. This may well happen if a layer of hard clay is near the surface. You can try to drill further, but as practice shows, hard layers are practically not drilled, especially if there is a rubble slab there (or you need special equipment, but it is expensive). There is only one way out: in the case when the pile extends less than a meter, you risk that the structure may simply slide on its side. If it is more or a meter, then you can cut the piles to the lowest possible level, then the house will stand, but again, the screw piles are located above the freezing depth. This is not criminal, but it does indicate that a different foundation had to be built here.
Concreting
It doesn’t have to be done because screw piles are quite capable of supporting any wooden structure without concreting, but they will not withstand a stone building even with concreting under any conditions. So, in my opinion, these are just unnecessary costs. Although minor.
Strapping. What's the best thing to do?
The strapping is made from different materials and in different ways: with timber, a multi-layer board, a corner, a channel are welded, or even tied together with a T-beam. Is it necessary? A wooden structure always has its own strapping or first crown, which can be laid directly on the headrests (after all, there are holes in them for a reason). Therefore, think carefully before tying, because compared to concreting, it is not such a cheap pleasure. Take at least the cost of one channel or timber 150x150.
Conclusion
Screw piles are a well-proven technology today. It has already gone through its own path of development and formation, and it cannot be called new, because it is an old military technique that not so long ago began to be used in industrial construction, and then in civilian construction. A screw foundation also guarantees enormous economic benefits, because its cost is 2–2.5 times lower than the same strip or monolithic slab. And practicality is an order of magnitude higher! In order to install a foundation on screw piles, desire alone is not enough; a lot of practical experience is required, so it is better to entrust this matter to professionals, and you already know how to control this process!
Text and photo: Konstantin Gusev, individual entrepreneur, suburban construction contractor
“Country construction” No. 2–3 (54), 2010
Is it possible to tighten screw piles without the use of special equipment? This is a question that requires detailed consideration. The literature provides step-by-step instructions for carrying out such work, but one can also come across an opinion about the insufficient reliability of supports installed independently.
Having analyzed all the arguments, it is advisable to make a compromise decision: it is better to entrust long piles with large diameters, intended for significant loads, to powerful equipment. This will increase the speed of work and ensure safety. When independently constructing light utility or domestic buildings or fencing structures, you can avoid spending money on renting special equipment and screw in the supports yourself. Piles for such structures are smaller in size, so their installation can be done by a friendly team.
Important: to install screw supports yourself, you will need help. It is almost impossible to cope with the work alone, even with the use of auxiliary tools.
Materials and tools
To mark a pile field with your own hands you will need:
- roulette,
- leg-split,
- metal rods (reinforcement).
Regardless of the method by which screwing will be carried out, it is recommended to choose ready-made piles from a well-known manufacturer. Making supports with your own hands is labor-intensive (with the exception of installing small-sized structures, quite a lot of supports will be required), requires the use of expensive equipment (welding machine) and certain skills. Buying cheap products from an unknown manufacturer or seller reduces the degree of reliability. In addition, supports made of low-quality alloys can become deformed or break during installation.
Important: When choosing piles, you should remember that their length must be sufficient to immerse below the freezing depth and to perform tying on the top of the supports.
To tighten the piles using only your own strength, you will need:
- two pipes acting as levers.
In addition to manual twisting, self-construction also uses a mechanized method, which will require:
- drill,
- geared impact wrench, which is commonly called a “meat grinder”,
- channel (can be used to strengthen the structure and prevent deformation).
Pile field marking
To mark a pile field with your own hands, you should determine the required number of piles. The total load is not difficult to determine, knowing the dimensions and material (its specific gravity) of the future structure. The load-bearing capacity of standard piles is known, indicated during marking, and, if necessary, it can be found in reference materials. Dividing the first value by the second and rounding the result up for insurance, we obtain the required number of supports.
If there are a large number of piles, it is easier to first draw their location schematically, adjusting the sketch if necessary, and then transfer the markings to the site.
When designing a pile field, it is taken into account that:
- The distance between adjacent supports in any direction should not be less than 3 m (otherwise sagging of the harness will be observed).
- Piles must be installed at the corners of the structure and along its perimeter.
On the ground, markings are made by installing reinforcement in place of the supports and connecting them with twine (to prevent sagging). During the process, the distance is controlled with a tape measure and the position of the marking elements using a level.
Installing piles manually
To install a pile with your own hands, you will need to make a significant effort. A lever design that can be assembled in several steps will help simplify the work.
- A crowbar is inserted into the holes in the pile.
- Pipes are put on the ends of the crowbar to increase the length of the lever.
Do-it-yourself screwing is best done with at least three people. Two rotate the screw support using levers, the third constantly monitors the position of the pile using a magnetic level. To ensure vertical installation, checks are carried out before starting screwing and then after each 360° rotation.
Installation using improvised tools
For mechanized installation of piles with your own hands, use a drill (with a power of 1.5 kW) and a geared impact wrench.
Elements of this design are connected using bolts. You should choose durable fasteners; for example, hardware sold in car dealerships will do. To prevent the pipe from deforming from the applied forces, you can increase the rigidity by laying a channel.
Since the gearboxes increase the torque from the drill, the pile enters the ground more easily. In this case, screwing the supports yourself is faster.
We should not forget about the need to control the position by level.
Support depth
A pile will serve as a reliable support only if it itself transfers the load to a dense layer of soil and does not sag under the weight of the structure. Therefore, screwing with your own hands, regardless of the choice of installation method, is carried out “all the way,” that is, until the moment when the soil, compacted during rotation, reaches such a degree of density that it does not allow further immersion. If the pile can still be screwed in, work cannot be stopped.
The main mistakes when installing a pile foundation yourself
- Leader drilling (making a shallow hole using a drill to ease the installation of a pile) or digging holes at the site of pile installation is a violation of technology. Such work disrupts the process of soil compaction during screwing, which leads to a decrease in the reliability of the foundation.
- Often, when screwing in with your own hands, the pile stops sinking into the ground before reaching the calculated depth. This means that the support collided with a stone or piece of rock. Such a pile should be left as is (later you will trim it to the general level) and an additional support should be screwed in instead of it next to it. Unscrewing and attempting to re-install is impossible due to loosening and reducing the bearing capacity of the soil around the support. Do the same if the pile deviates from the vertical during installation. To avoid overuse of supports, it is recommended to constantly monitor the position, as mentioned above.
Installation of a pile foundation after installation of supports
After you have installed all the piles with your own hands, the supports are leveled in height using a level. Thus, the upper parts of the supports should form a flat horizontal plane.
Having trimmed the screw piles, they will be filled with concrete mortar, which, depending on the required volume, can be prepared manually or using a concrete mixer. When filling piles with concrete, make sure that there are no voids left. The subsequent stages are started immediately, without waiting for the solution to gain strength.
Heads are welded onto the piles.
Mount the harness from a channel or timber.
Alternative options
It is often recommended to use more powerful equipment when installing a pile foundation with your own hands. The so-called pile drivers are transported in the trunk of a car, but have significant power. Purchasing such equipment at a price of about 150 thousand rubles for private housing construction is unprofitable, especially if you yourself plan to install supports only for fences and light buildings.
If it is possible to rent such equipment, it is worth considering the option as an alternative to installing supports manually.
How to tighten screw piles with your own hands? updated: February 26, 2018 by: zoomfund
Installing screw supports is a rather labor-intensive process. Screwing in screw piles with a “meat grinder” is an affordable alternative to expensive mechanization (and easier than manually).
There are several ways to install screw supports. The main difference between these methods is the degree of mechanization. We will mention them at the beginning in order to better understand the pros and cons of tightening screw piles with a meat grinder.
Assembling the “meat grinder”
So, screwing methods:
- Completely manual method;
- Manual electric or hydraulic pile driver;
- Special machines for driving piles, often on a truck chassis or as detachable equipment on an excavator.
Design and options of “meat grinders”
“Meat grinders” are a hand-held tool consisting of an electric or hydraulic drive mounted on the head of a pile and a lever system for fixing the tool and transmitting torque to the pile.
The name comes from the torque amplifier (TMA) for the wheel wrench of the truck, nicknamed the “meat grinder”
Torque booster (TCA)
Drive requirements
It is rational to choose a drill of sufficient power as a drive. In the absence of electricity on site, a mobile generator will be required.
- The power of the drill must be at least 2 kW;
- It is also important to have reverse and change the rotation speed.
Of course, you can use a hydraulic motor. But it’s easier to buy a drill, and easier to replace if it breaks. And the portable hydraulic unit needed to operate the engine will hardly be useful to you anywhere else.
Motor drill - can also be used in this design
If you decide to use other motors instead of a drill, they should be no worse.
Gearbox requirements
A gearbox is needed in the design to increase the moment on the pile head and reduce the speed:
- The gearbox must withstand a torque of at least 4500 Nm;
- The gear ratio should be greater 1:60 .
When choosing RCM, give preference to designs with bearings.
Also pay attention to the ease of changing lubricant. It is recommended to change the lubricant after installing 20 piles.
After purchasing, fill the gearbox well with new lubricant (there won’t be enough of it). It is recommended to replace the lubricant with a more suitable one: for example, grease for CV joints.
Adapter
The adapter looks like 2 adapter mounts (for a drill and a gearbox) and a frame connecting them together. As picture:
Purpose: so that the gearbox does not rotate relative to the drill. Otherwise, you will have to hold both the drill and the gearbox while working.
Nozzle, levers, etc.
Our pile driver will transmit torque to the pile through the nozzle. The forces on the head are significant and the pile may collapse. And this is marriage.
There are two nozzle options: internal and external. They differ only in that the nozzle is inserted or put on the pile.
The nozzle should have a hole where the finger will be inserted. It's good to make this hole oval.
In order for the pile to rotate in the ground and the pile to be twisted, a lever must be attached to the frame. The lever may have a hinge that allows it to swing up and down, but not left and right. This is necessary for the convenience of driving high piles and controlling them from the ground without platforms.
Features of screwing screw piles with a “meat grinder”
We will not now dwell on such important issues as those discussed in other articles, such as the selection of piles, calculation of the pile field, site marking, etc.
To reduce the effort for screwing the pile, you can pre-drill a hole with a diameter slightly smaller than the diameter of the pile spindle.
It is convenient to do the work of screwing in piles with three people.
You need to start by installing corner piles.
Sequence of actions:
- Place the pile next to the installation site;
- Connect the “meat grinder”, including the lever;
- Install the pile vertically according to the markings (pile driver at the top, hold the lever so as not to interfere);
- One holds the lever, the rest hold the pile so that it does not deviate from the vertical;
- Turn on the “meat grinder”, control the vertical position of the pile, continue until the pile is immersed to the desired depth.
Details of screwing piles with a “meat grinder” can be seen in the video:
- Priming. Is it possible to make such a foundation on your site?
This is a very sore point for many and perhaps the most important one. Experience shows that there have never been cases when screw piles could not be tightened. It always worked out, but foreign objects that appeared along the route still made their own adjustments to the pile field - some piles went out of line. No one is immune from this and we must always be prepared for it. There is an unknown factor in any business. For screw piles, such factors are stones, tree roots and other unidentified objects that are located underground. The only savior for a pile that is out of order is the cap; its platform compensates for the departure from the center of the line and will allow, at least partially, to capture the frame for the future structure. There are two ways to determine the success of screwing: knowing your soil and test drilling (or screwing). Knowledge of the soil is mainly limited to the presence of stones in it - if there are a lot of them there, then most likely it will not work out. If they exist and come across periodically but not in continuous deposits, then you can try and most likely screwing will be successful. In general, all types of soils, except rocky ones, are suitable for screw piles. The second method is drilling or screwing. In our opinion, drilling is much more effective than screwing because when drilling we see and probe the soil, we can make markings and prepare holes of a smaller diameter, so that we can then bring screw piles and quickly screw them into the existing markings. And screwing is just a banal poking of the pile in different places at random... It won’t work. This method is unprofitable and ineffective. We have never done this and will not do this. Only drilling or simple soil analysis will help determine by 90% the possibility of screwing piles. So, you have determined that the screw piles on your site will be screwed in and we move on to choosing the piles themselves...
- Select the diameter and length of the pile.
Today, the diameter of screw piles from different manufacturers varies from 47 to 108 mm; piles of larger diameter are possible, but this is on special order. Small diameter piles, from 47 to 76 mm, are mainly used in the construction of fences or fortifications. The “89” mm pile can be used in the construction of frame houses or light structures, but we will not consider all these piles, because they always come as auxiliaries. Let's focus our attention on the 108 mm screw pile. Such a pile can withstand a load of up to 3500 kg! This means that on such a foundation you can build all types of houses except stone ones and have no doubt about its strength - the foundation will serve faithfully for many years. You just need to calculate the quantity correctly. It's not difficult to do this. It is necessary to calculate so that the bearing capacity of the foundation is 30% greater than the weight of the structure, taking into account additional loads, i.e. there was a margin of safety. The length of the pile can also be taken with a reserve, because it is easier to cut it than to weld an additional pipe to the pile, but still count on at least the fact that the pile goes to at least a freezing depth of 1.5 m, or better yet, penetrates half a meter of clay. The most popular piles are 2-2.5 m. After you have calculated everything correctly, you order screw piles from the factory and take them to your site.
- Screwing tool.
The tool plays a very important role in the process of screwing screw piles. One might even say dominant, because The result of screwing directly depends on it. I would like to list a simple set of tools, without “special devices”, which can be easily assembled in hardware stores. So, let's begin...
1) Shovel - useful for leveling the surface where the pile will be screwed.
- Level 30 cm, on a magnet - attached directly to the pile during screwing to control the vertical level of the pile.
- A hydraulic level of at least 15 m is necessary to set the horizontal level of the piles.
- A tape measure of at least 20 m is necessary for taking measurements.
- Nine rods of reinforcement A12, 1 m each, are necessary to mark the pile field; twine is wound around the entire perimeter of them. As an alternative to reinforcement, you can also use ordinary pegs, but then they should be as even as possible.
- The scrap metal is threaded through the pile and then pipe-levers are put on it on both sides.
- Two “50” pipes, 2.5 m each - they are put on the scrap on both sides and serve as levers for screwing in the pile.
- A hammer or small sledgehammer is useful for driving rebar or pegs into the ground.
- Garden drill - the drill must be smaller than the diameter of the piles that you will screw in. Its role in the screwing process is to drill guide holes or probe the soil under the pile field. The depth of the hole must be an order of magnitude shorter so that the screw pile can independently travel a certain path and become compacted in the ground.
- Twine with a total length of 180 m - it serves for marking, as well as beacons for visual monitoring of the displacement of the screw pile. If it remains, it will never be redundant.
- Grinder and cutting wheels - for cutting screw piles one level at a time.
- Extension
- A special marker or a construction pencil - one of two things. They will be useful for marking
14) A sheet of thin cardboard - necessary for “outlining” an even circle on
screw pile when the process has come to leveling at one level. At this mark
and cut off the pile. To make the line even, you need to wrap the pile with a sheet
cardboard and align the ends at the mark, then draw a straight line
circle.
- "Tourist" knife - useful for cutting twine, etc.
- Gloves - so you don't have to work with bare hands.
- At least two assistants for screwing is not an unimportant point. The ideal option is two installers and one person who will look from the side at the vertical level of the screw pile, at the row line, etc.
You also need to have electricity, and if you don’t have it, then a generator. It is rare that there are cases where piles are not trimmed.
4. Make markings.
The markings must be calculated very carefully, down to the millimeter. It is made from two components - reinforcement and twine. In most cases, the foundation has the shape of a square or rectangle. If yours is the same, then first we need to set the outer perimeter and screw the piles into the four corners. It is from them that the entire foundation is built. We take a tape measure, a drawing, eight bars of reinforcement (two for each corner),
twine and let's start... The first thing we need is a connection to the site, or the so-called “starting point”. In our case, you know perfectly well where the foundation should be, so we need to draw the first line of any side of the foundation; it must be unshakable and cannot be touched because the geometry of the entire foundation is built from it. You can move all other sides to set the desired size. We measure so that this side is parallel to the fence, road, etc. and stretch the twine, tying it to two reinforcement bars driven into the ground. The line should be stretched more than the future size of the foundation. In general, each future line of the foundation is made according to its dimensions; as a result, all marking angles turn out to be criss-cross. This is necessary so that the reinforcement does not interfere with screwing, and the resulting “flexible” corners, with the help of twine, can control the screwing of the pile. Pay attention to the photos: 
After you have pulled the twine on four sides and done it so that the dimensions of all sides converge at the intersections of the twine, and the diagonals of your rectangle are equal, you can start drilling. Attention!!! It is important!!! If you make the foundation along the “centers”, along the edges or in some other way, you need to make the size of the twine larger, because each pile needs to be fit into the corner of your marking; accordingly, the “center” size will be slightly smaller than the “lace” size. You will understand what I want to say when you read everything to the end or apply it in practice from your own experience.
5. We drill holes. 
The holes are drilled with any drill - garden, homemade, motorized drill, etc., but the holes must be smaller in diameter than the piles themselves. All this is necessary in order to direct the pile along the trajectory we need, to give it a direction of movement. The depth can be any, but slightly shorter than the pile itself. If you try to tighten the pile without “guides”, it will crawl along the ground to the right or left and you are unlikely to get the required size. In some cases, without a guide, the pile does not go into the ground at all. Try both options and see for yourself. You need to drill holes in the center of the corner so that when you place the pile, the pile fits clearly into the corner, without moving away from the twine or squeezing it. In moderation. As shown in the photo above. Once you've drilled through the first four corners, you can start screwing.
6. Screw and level: along the lines, horizontally and vertically.
We put the pile in the corner. We attach a magnetic level to it and thread a crowbar through it. To begin with, levers are not needed because... At the initial stage, much effort is not required. 
We begin screwing and monitor the displacement of the pile to the sides. Throughout the entire process, the pile must be clearly in the corner, this is extremely difficult to do, it will move to the side and move away. We will tell you how to level it in step 7. In the meantime, we need to screw four piles into four corners. As the resistance of the pile increases, we put on the levers. You need to twist with equal effort from all participants. Uneven force on the levers will lead to even greater displacement of the pile, so you need to try. Two rotate, one constantly looks at the vertical level on both sides and the displacement of the pile, immediately correcting if necessary. If the soil is passable, you can immediately set four piles at the hydraulic level, this will allow you to subsequently control all the lines and align the remaining piles at this level. After you have screwed in the first four piles, remove the markings and wrap the twine around the piles themselves, because we still need lines to line up the remaining piles. If the piles are at different heights, then the level can be given through the twine and subsequently be oriented using it. Look at the photos...
Please note that all the corner piles are screwed in and level, and there is also twine wound around them and also level, but about sixty centimeters below the screw piles themselves in order to make it convenient to walk. We need twine in order to further screw in the piles around the perimeter. It's easy to do. We take the reinforcement and make transverse markings for the next line of screw piles. We drill holes and fit side piles into the resulting corners. We don’t touch the internal ones for now, we rotate the piles along the entire outer perimeter, then all the internal ones...
The web grows and we tie twine to each opposite pile. Subsequently, all internal intersections of the twine automatically provide places for screwing in the new screw piles we need. All that remains is to drill and screw. Walking is becoming more and more difficult and you must always be on guard so as not to rip or disturb the beacons in the form of twine. This, of course, is not very convenient, but all the inconvenience is more than compensated by the result - all the piles stand together in a row no matter which way you look. This technique also increases the time of work, but also allows you to control the displacement of the pile, which cannot be done by “stupidly” screwing them into the ground, relying on your “diamond eye.” Only this method can achieve the most accurate dimensions and decent results. However, I dare to disappoint you - it will never work out perfectly. Still, nuances arise on the way to completing the work. Look at some moments of screwing in the photographs, after which we will move on to analyzing and correcting any nuances that arise. 
7. There are nuances:
- what to do if the pile goes to the side?
The pile itself will never go straight; it needs to be guided. As soon as you start to twist, the pile will begin to shift due to its screw device. Leveling the pile is not difficult and there is only one trick: you need to tilt its top as much as possible in the direction of displacement and twist it in this position for a certain time, then level it again and see the result. If it is in place, continue to screw it evenly; if it is not there, then tilt it again and continue to screw it at an angle until it is in place. This is the same as screwing a screw into wood. Experiment. They also use special devices to forcibly fix the pile and prevent it from moving from the center, but we are considering simple screwing. Look how the alignment looks in the photo... 
In this photo, the pile went into a corner and crushed the twine. In order to return it back,
we tilted it in the direction in which it had shifted, twisted it a little, aligned it and looked at the result - it stood in the place we needed, clearly at the corner of intersection
twine. In this way, the movement of the screw pile can be easily manipulated. When all the centers are aligned, the tops of the piles still do not meet. Leveling the top of the piles is also simple: you need to pull the twine over the top of the piles from one extreme to the other extreme screw pile in a row and, with the usual physical force of two or three people, swing it and bring it to the line. The result is exactly: 
- what to do if you come across a stone or other object?
There are several options here and there can be no statistics here, each case is individual. What can be done? 1) Try to pass this place with the screw pile itself using a good force on the levers. With a grinding sound. Sometimes it helps. It happens that even the blades bend, but it’s still worth trying this option first. 2) Unscrew the pile back and try to remove the obstacle from the hole. If the obstacle is large, then it can no longer be pulled out. What then? 3) Then, if the pile is not angular and goes more or less decently into the ground, well, let’s say a meter... You can leave it in place. I understand that it did not reach the freezing depth... But imagine if you screwed in twenty-one piles and stood on the last, twenty-second?)) The last option remains... 4) Move the foundation. This can be safely done if you encounter similar obstacles at the first stage, when you are tightening the corner piles. If the corners fit well, you can force it with the rest. This is why corner piles rotate first.
- what to do if the pile goes shallow and doesn’t go any further?
This may well happen if a layer of hard clay is near the surface. You can try to drill further, but as practice shows, hard layers are practically not drilled, especially if there is a rubble slab there. Or you need special equipment, but it is expensive. There is only one way out. If the pile extends less than a meter, then you risk that the structure may simply slide onto its side. If it is more or a meter, then you can cut the piles to the lowest possible level, then the house will stand, but again, the screw piles are located above the freezing depth. This is not criminal, but rather indicates that a different foundation had to be made here...
8. Additionally:
- concreting. Should I or should I not?
It can not be done because screw piles are quite capable of supporting any wooden structure without concreting, but they will not withstand any stone structure even with concreting under any conditions. So, in our opinion, these are just unnecessary costs. Although not significant.
- harness. What's the best thing to do? Or not to do it at all?
They are made from different materials and in different ways: with timber, a multi-layer board, a corner is welded, a channel is welded, or even connected with a T-beam... Is it necessary to do this? Speaking about the fact that screw piles can only support wooden buildings, we know that each of such buildings always has its own strapping or first crown, which can be made directly onto the headrests (after all, there are holes in the headrests for a reason), so think carefully , before doing the strapping, because compared to concreting, this is not such a cheap pleasure. Take at least the cost of one channel or timber 150x150?
Conclusion.
In conclusion, we can say that screw piles today are a well-proven technology. It has already gone through its own path of development and formation, and it cannot be called new at all, because it is an old military technology that not so long ago began to be used in industrial construction, and then in civilian construction. In addition, there is also a colossal economic benefit - after all, the cost of such a foundation is 2-2.5 times lower than the same strip or monolithic slab. And practicality is an order of magnitude higher! Well, to tell the truth, if you are going to and still decide someday to screw in such a foundation yourself, then we can tell you that this requires serious experience of a specialist who has worked a lot on such foundations. Therefore, it is better to entrust this matter to real professionals!
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