How much to tighten the hub nut. How much torque to tighten the hub nut

In this article, we will talk about how to unscrew a stuck nut, a rusty nut, a nut with torn edges or a completely round one. Cases with non-standard nuts - plastic and big size.

The material also describes the most suitable tool, incl. a special tool professionally used to work with fasteners.

The material is useful for those who intend to unscrew the fasteners of the engine crankshaft, hub, wheel, generator, exhaust manifold, variator and other components and assemblies of a car, motorcycle or other equipment.

How to unscrew the nut

As a rule, nuts are unscrewed with manual metalwork tools - box or open-end wrenches, heads using a wrench or ratchet. However, problematic situations often occur.

How to unscrew the nut when the nut cannot be unscrewed with a conventional tool with the usual application of forces? In this situation, from the available tool, choose the one that fit better Total:

• thin short open-end wrenches, especially with a too free (broken) pharynx, are the worst option, which is better to refuse immediately in a situation with unscrewing rusty stuck nuts (open-end wrenches will lead to torn edges and further difficulties);
• box wrenches with an elongated handle are preferable to open-end wrenches, since they cover the perimeter of the nut more tightly;
• A 6-point ring wrench or head is preferred over their 12-point versions;
• due to its simplicity and strength, a wrench is preferable to a ratchet, because for the latter, the application of increased force may damage the mechanism (this is especially true for ratchets with big amount teeth, each of which is smaller and not as strong);
• an impact wrench will do a better job than a hand tool;
• in combination with a long wrench or impact wrench best solution there will be a Super Lock head, in which the force is applied not to the corners (faces), but to the planes, which eliminates the licking of the nut faces;
• a moment amplifier (multiplier) will help to apply a force to a large stuck nut that is inaccessible when using only the physical capabilities of a person.

In which direction to unscrew the nut

In the vast majority of cases, fasteners have right direction threads: unscrew the nut counterclockwise (we look at the nut from the side of the free threaded end of the bolt or stud through which it is necessary to drive the nut).

Accordingly, unscrew the nut with a left-hand thread clockwise.

When deciding in which direction to unscrew the nut, it is enough to carefully look at the fasteners:

• on the side you can see the inclination of the threads at a small angle - unscrew the nut in the direction in which the thread "rises";
• even if the threaded part is not visible, you can see the desired direction along the end of the nut at the exit point of the last turn of its internal thread.

How to loosen a stuck nut

In order to unscrew the stuck nut, we recommend that you perform several preliminary preparatory operations:

• clean the fasteners from rust and dirt with a metal brush;
• tap the nut in a circle with a hammer without damaging its edges and open threads.

When deciding how to unscrew a stuck nut, you need to take into account several possible ways, based on the actual state and availability of fasteners for the tool, the composition and parameters of the existing tool, the feasibility of destroying the nut itself or the threaded part on which it is fixed.

The following options are available to unscrew the stuck nut:

• apply heat to the nut (preferably until red and repeatedly);
• apply a penetrating compound (WD-40, liquid wrench or their analogues) into the contact gap of the nut with the thread of the bolt (stud), withstand the time required for the preparation to work (from 20 minutes or more depending on the state of the fasteners and the activity of the agent);
• increase the force effect on unscrewing by increasing the force application lever by using an elongated tool (or extension nozzle for a tool of normal length);
• apply a special device - a moment amplifier (another name is a torque amplifier, moment multiplier);
• use a pipe wrench, clamping the nut with it and applying force in the direction of unscrewing;
• clamp the nut in a rigidly fixed vise and unscrew it by rotating the entire part or assembly, if possible;
• clamp a small separate vise and try to unscrew the nut with them;
• use a pneumatic impact wrench;
• drill out the threaded rod on which the nut is stuck.

How to unscrew a broken nut

Damage to the edges (their failure) causes serious difficulties. Major decisions in this case some:

• use the Super Lock head (affects planes, not edges);
• clamp the torn nut in a pipe wrench (in a vice, clamp, pliers, etc.) and unscrew it;
• hammer a larger nut of a suitable size on top of the nut with licked edges, the inner diameter of which allows it to be put under tightness, for additional fixation, drill a recess in the contact zone of the nuts by inserting a metal rod (a fragment of a drill and a piece of a nail) into it as a key to prevent rotation) and unscrew the fasteners using a tool sized for a larger diameter nut with working edges;
• put on a nut of a larger diameter, weld both nuts together with a semi-automatic welding machine (while closing the thread of the stud or bolt with a tube with a suitable wall thickness), unscrew the large nut together with the welded small one.

How to loosen a round nut

For round nuts, when the edges are cut and smoothed completely by previous unsuccessful attempts, or the nut is made in this form from the very beginning, several approaches can also be applied:

• fit a standard hex nut of a larger diameter into the tightness on it and drill a hole and a key locking it from rotation on the line of their contact and unscrew it by the large nut;
• with a sufficient height of the side surface, use a special tool - a stud driver;
• put on a round nut a square washer of large thickness (comparable to the height of the nut), cut on one side and with an inner diameter of the washer exactly corresponding to the outer diameter of the round nut, tighten the nut with a pipe wrench or vice, succumbing to compression, the nut in the section will select the gap until the surface is tightly covered round nut, unscrew the fastener.

In the latter method, picking up a washer from a stock is unlikely, so it is easier to make it yourself from a suitable piece of metal.

How to unscrew a nut with its heating

Heating a nut is often affordable, simple and effective way. When the metal is heated, the threaded surface of the nut expands, the corrosion adhesion is somewhat destroyed, and the adhesion to the thread of the bolt or stud weakens.

Any suitable heat source can be used for heating: matches, a wax candle, a lighter, a gas can burner, a blowtorch, a gas cutter (carefully, at a sufficient distance so as not to melt the fasteners), etc.

If possible, it is better to heat the nut red hot and unscrew it. If the first time did not work, then the heating should be repeated several times. This may be especially true for nuts planted on special agent- thread lock.

How to unscrew the nut with soaking

Fastener loosening with soaking is further development relatively quick (20 minutes or a little more) application of special penetrating compounds.

The threaded part of the nut is usually the same great height, therefore, if there is sufficient time for a long immersion in a rust-penetrating or chemically active compound, it is an effective solution.

There are two main approaches:

• Moisten abundantly rusty fasteners in the thread area active agent, wrap the accessible threaded shank of the bolt or stud in the area of ​​the nut with a rag soaked in this agent or put it on top of the end (if the shank does not protrude beyond the plane of the nut), cover with cellophane or rubber and wrap;
• immerse fasteners in chemistry completely.

It should be ensured that the penetration of the active composition occurs strictly vertically from top to bottom.

Chemistry can be used:

• penetrating compounds, in addition to the previously mentioned WD-40 and means " liquid key”, kerosene, gasoline, carburetor cleaner, lock defroster and others can be used;
• rust converter;
• compositions chemically active in relation to rust - table vinegar, iodine, alcohol, Coca-Cola, etc.

How to unscrew a big nut

For large nuts, 6 main methods can be effective:

• use a special tool that is designed for the repair and maintenance of agricultural machinery, tractor and special equipment- torque amplifier (other names - torque amplifier, torque multiplier);
• use a wrench with a long handle or a socket with a long knob corresponding to the size of the nut (if necessary, use a special extension or put on a pipe right size on the swivel outer end;
• in the absence of a suitable key or head, cut a notch in a strong metal strip from one edge strictly along the distance of the parallel faces of the nut, thereby creating an individual key for a large nut;
• use a chisel and a hammer to strike on the face of the nut in the direction of unscrewing;
• weld a metal bar to a large nut by electric welding (as an option - a corner, channel or other profile) as a T-shaped or L-shaped handle, for which to unscrew;
• if the threaded end of the bolt or stud does not protrude beyond the outer surface of the nut, then you can drill 2 recesses in the large nut from this side, then drill 2 holes in a strip of thick metal (corner or other profile) at the same distance, align the holes and insert into them metal rods, apply force to unscrew (the rods will work like shear keys, transferring torque to the nut).

The last 2 methods can be combined: welding a metal profile with a flat surface to the outer upper plane of a large nut, additionally drilling a couple of holes and inserting dense metal rods that will work like shear keys when force is applied. This will significantly strengthen the welded joint.

When deciding how to unscrew a large nut, one must proceed from the need to maintain the integrity of the nut.

How to unscrew a plastic nut

Plastic nuts, as a rule, differ in the shape and size of the working surfaces from ordinary metal nuts. The pliability of the material limits, although not always excludes, the use of a tool that compresses on both sides ( pipe wrench, vise, etc.) - you need to cover as much of the perimeter as possible.

You can unscrew the plastic nut:

• special factory-made key, working surface which repeats the profile of the perimeter of the nut;
• self-made key;
• oil extractor car filters, which tightly cover the circumference with a steel tape or several metal paws (the stronger the applied force, the stronger the coverage);
• press wooden blocks and two opposite sides to the protrusions of the plastic nut and simultaneously hit with hammers together in the direction of unscrewing;
• with a small diameter - wide opening pliers;
• pipe (gas) wrench.

If the standard key is lost, then it is easy to make a key with your own hands from not the most difficult metal (steel or aluminum) or dense plastic. First, it is more reasonable to make a template out of cardboard, check the tightness of the fit on the plastic nut, and then transfer the contour to a suitable piece of sheet material and cut it out taking into account the handle.

How to loosen a nut hard to reach place

To work with hard-to-reach fasteners, a special tool is used:

• wrench or ratchet with a short handle;
• ratchet with a large number of teeth in the mechanism (gives a small angle of rotation, which is important in cramped conditions);
• extensions to the heads;
• flexible drives for heads.

When deciding how to unscrew a nut in a hard-to-reach place, you must first find a suitable tool - purchase or ask for a while.

How to unscrew the nut with its destruction or damage

In the most hopeless cases, when all available ways and the tools did not work, the fastener remains to be disconnected by destroying the fastener:

• extending the chisel to the edges of the nut, hit it with a hammer in the direction of unscrewing;
• cut fasteners with a power tool with a cutting wheel;
• cut with a manual hacksaw for metal;
• destroy the nut by drilling numerous holes;
• cut the nut with a chisel and a hammer (easier - after pre-drilling the holes);
• use a tool specially created for this - a wrench;
• put on a larger nut, weld both nuts together around the perimeter with a semi-automatic welding machine (while closing the threaded part of the bolt or stud with a tube with sufficient wall thickness to prevent welding into one whole), unscrew the large nut with a wrench.

Conclusion

When deciding how to unscrew a nut, it is very wise to immediately use a suitable effective tool and perform preliminary training taking into account the condition of the fastener. Unprepared use of brute force with the wrong tool is highly likely to damage the faces of the nut, break the stud or tool.

Before unscrewing the nut, it is worth cleaning the threaded part of the stud or bolt, applying a penetrating compound, and only then apply force. With the techniques described in this article, even the most difficult cases can end in a positive outcome if some extra time is spent on preparation.

Returning to this article when it is needed, you can find the necessary hint in answering the question of how to unscrew the nut of the engine crankshaft, hub, wheel, generator, exhaust manifold, variator and other components and assemblies.

In case you notice that front wheel dangles a little - be sure to eliminate the backlash. In many cases, the wheel bearing is the culprit for wheel wobble. The problem can be detected when driving over a curb or other obstacle. At the same time, you will feel a certain “emptiness in the wheel”. It is not uncommon for a backlash problem to be solved by tightening the wheel bearing. On cars of the classic Zhiguli family, work on tightening bearings is extremely simple. In order to check the play in the bearings, it is necessary to jack up the wheel so that it is off the ground. Then you should take hold of the upper and lower edges of the wheel, you should swing it. If the wheel dangles in a vertical plane (up-down-for sure it's bearings). If the wheel dangles along a horizontal axis, pay attention to the ball bearings.
So for yourself, you have already decided that the bearings should be tightened. What do you need for this? - the minimum tool: a key for 19, for unscrewing wheel bolts and a head on 27 - it is necessary for tightening the adjusting nut. You will also need two hammers. One is bigger and the other is smaller. A new shim will come in handy as well as a straight screwdriver. Now about everything in detail and in order! The front hub bearing is adjusted as follows.
1. At the very beginning of work, it is necessary to put the car on hand brake and transmission. Put shoes under the wheels. This is necessary so that when hanging the car does not jump off the jack.
2. The second step is to prepare the wrench for the wheel bolts. On classic models Zhiguli for this, a key of 19 is used. It must be with a head, do not try to remove the wheel with a ring wrench! With this key, we loosen the tightening on the wheels - the car is still standing with the wheel on the ground.
3. After the bolts on the wheels are loosened, the wheel should be jacked up. Pay attention to the surface on which the jack rests. It should be even and firm. If the ground is soft under the car, a board can be used as a support for the jack. When the car's wheel is off the ground, place a spare wheel under the lower front suspension arm - just in case. Suddenly the jack will not stand up - unlikely, but possible.
4. When the wheel is hung out, and under lower arm there is already a spare tire, you should unscrew all four bolts on the wheel and remove the wheel. You will see brake disk, as well as the so-called "cap" of the hub. The cap must be removed. After all, it is under it that the adjusting nut is hidden. To remove the cap, you will need a medium-sized straight screwdriver and a hammer. A screwdriver should rest against the cap, and then, without strong blows, knock it out. Blows should be light, and they should be applied along the entire circumference of the cap.
5. When you have already removed the cap, you can easily see the nut, it is she who regulates the tightening of the wheel bearing. great attention pay attention to the "Trunnion" - the element on which the nut is screwed. The trunnion has two channels-recesses, they serve to lock the nut. The shoulder of the new nut is “driven” into these channels - this is how the lock is made.
6. The old nut should be unscrewed. In this case, in many cases it is necessary to clean the old trunnion channel from the elements of the nut. Pieces of the nut may have remained in the trunnion after the last alignment. You can use a small screwdriver for cleaning.
7. The old nut is unscrewed. And you start to tighten a new nut. Exactly at this moment the front wheel bearing is tightened. Under no circumstances should the nut be tightened with all its force! In the process of tightening the nut, you should shake the wheel in a vertical plane and scroll. The wheel should not dangle, but it should spin with ease. If you tighten the adjusting nut - bearings will be clamped and probably in this position will soon fail. Too little tightening will lead to "bumpiness" of the wheel. The tightening torque of the adjusting nut is the most important in the whole operation. It depends on the tightening how long the bearing will last and how well it will perform its function.
8. To determine the tightening torque at which the wheel does not hang out and at the same time rotates easily, put on the hub rim with a tire and tighten it with two bolts. In the process of tightening the adjusting nut, the wheel should be chatted and scrolled. Determine the moment when the wheel dangles, then gradually tighten the nut. Tightening should be stopped as soon as the wheel stops dangling, no need to tighten the nut more. The wheel should turn easily, but there should be no wheel wobble.
9. When you find the optimal position of the nut, it will need to be locked. Despite the rather tight tightening of the nut, it may well loosen or, on the contrary, tighten over time. Therefore, for locking, we use special nuts with a collar.
The shoulder is punched with a hammer, through a screwdriver, a chisel or reverse side the second hammer and presses into the groove of the trunnion. Locking is best done with the wheel lowered to the ground. The wheel tightened on two bolts should be lowered from the jack. In this case, the blows from the hammer will not be transmitted to the bearings so much.
10. The nut cap that was previously removed should be cleaned of old grease and new grease should be hammered into it.
11. After locking, the car should be raised again, remove the disk with the tire and carefully, with a hammer, drive the hub cap into place.
12. Then you can put on the disk again, bait the bolts, lower the wheel and tighten it.
13. When leaving the road after work, Special attention give the sounds in the car. Not a note should be heard from the bearing! If the bearing hums, loosen the adjusting nut. In this case, you will need another nut to re-lock.
The work described above is up to the most ordinary motorist. Front wheel bearing tightening is carried out within one hour of time, you will also need the desire to solve the problem yourself.

One of the most important elements The undercarriage of the car is a wheel bearing, which ensures uniform, unhindered and silent rotation of the wheel. The hub bearing type refers to rolling bearings.

Currently, collapsible and non-collapsible hub assemblies are installed in cars. In the first case, the bearing can be replaced. In the second, it is necessary to change the entire hub assembly. According to unreliable information, non-separable ones are safer than collapsible ones. However, they market price exceeds several times. Our domestic locksmiths manage to cut with a grinder connecting elements and replace the bearing in a non-separable hub.

Non-separable rear wheel hub

On vehicles with one-piece, non-separable assemblies, bearing adjustment is not possible.

The adjustment process consists in establishing a backlash between the hub and the axle shaft, pressing the inner race against the outer. Most vehicles with rear drive are produced with single row roller bearings. A pair of such bearings is installed in the assembly, capable of withstanding large radial and axial loads. Maximum loads are transferred to both the rear and front bearings when driving on rough roads, which leads to premature technical wear of the part. Also an important cause of failure is a sharp change in temperature. For preventive purposes, the front and rear bearing assemblies must be inspected every twenty to thirty thousand kilometers. If your vehicle has single row bearings they must be periodically lubricated with special grease lubricants and pay special attention to the axial distance. If bearings are installed closed type seals need to be checked. Wheel bearing failure is a fairly common problem. Well, if a breakdown is detected on time, it happens that the bearing falls apart high speed which causes the wheel to spin. Bearing failure is often associated with incorrect adjustment. In cases of detection extraneous sounds accompanied by a beating, when hitting a bump, a pit, it is necessary to diagnose and identify a malfunction. In many cases, the wheel bearing is the culprit. But not always. For self diagnosis Jack up the wheel where the sound is coming from. Grasp the upper part with one hand, the lower part with the other and pull the wheel in a vertical plane. If the wheel dangles, then it is a bearing or a lower ball joint. To check ball joint it is necessary to slightly raise the support with a second jack. Shake the wheel, if the play does not disappear, then this is the bearing. Otherwise, the problem lies in the ball joint. Before deciding to replace a bearing, you can first adjust it. If that doesn't help, start replacing.

You can check the bearing on a "jacked" wheel

Bearing adjustment can be carried out after it has been replaced or the above symptoms occur. If the wheel bearing is overtightened, the wheel will become very hot, and the bearing will be destroyed. When excessive big backlash high probability of collapse of the bearing and seat. Minimum clearance allowed. Lift wheel bearings does not take much time and is quite easy. Prepare a minimum set of tools:

• set of wrenches,
• Screwdriver Set,
• litol,
• a couple of hammers
• adjusting washer,
• set of heads,
• a new nut (take from the kit or buy separately),
• wd-40 (can be gasoline),
• a torque wrench can be used for fine adjustment.

It is needed in order to measure and regulate the force applied when tightening. However, not everyone has such a tool, as it is quite expensive. In this manual, tighten the nut by hand if a torque wrench is not available.

Instructions for self-tightening wheel bearings.

1. Set the vehicle to speed or parking brake. Place something under the wheels, such as wheel chocks. This is necessary so that the car does not fly off the jack.
2. Take the balloon from the kit in the trunk (if any) and loosen the bolts securing the wheel. The car must be in a non-raised state.
3. Prepare a place to install the jack (from the kit). It should be firm and even. You can put boards under the jack if necessary. Raise the wheel until it is no longer touching the ground. Put a chock under the lever just in case. Suddenly the jack is unreliable.
4. Loosen the bolts completely and remove the wheel.

   

5. The next step is to remove the metal cap from the hub. To do this, use a flat screwdriver from the kit and a hammer. Place a screwdriver between the cap and the hub and light blows detach the cap. Hits with different parties to avoid snacking. The nut for adjusting the bearing is located under the cap.

   

   Removing the hub cap

6. Remove from cap and nut old grease. You will see a lock nut threaded onto the shaft. It is used to tighten and loosen the bearing.

   

7. The old nut needs to be unscrewed. To do this, use a socket from a set of the appropriate size. Clean the trunnion (the part of the shaft where the nut is screwed on) with gasoline or wd-40.

   

   Unscrew the old nut

8. Replace the old nut with a new one. Reinstall the wheel. First, fully tighten the nut so that the wheel stops turning easily. Then gradually loosen, rotate and dangle the wheel vertically until it begins to spin freely. Tighten the nut slowly and with care so as not to break. Backlash should be minimal, barely perceptible. The tightening process is the most important action. It is he who affects the quality of the work performed and the life of the wheel bearing.
9. Using a hammer, chisel or screwdriver, lock the nut on both sides where there are grooves on the trunnion. To do this, attach a chisel with a point to the shoulder of the nut and hammer it into the groove with a hammer. This is necessary so that the nut does not change position during operation, which can lead to weakening or tightening of the bearing.

   

   You need to lock the tightened nut

10. Fill the cap with new lubricant and put in place. Remember that if the wheel alignment is incorrect, the toe-in changes, as a result of which the vehicle's handling deteriorates, fuel and lubricant consumption increases, tires wear out quickly and unevenly.

The described process can be clearly seen in the following video: Remember to check the bearings periodically. This way you ensure your safety on the roads. Best regards, PodshipnikTsentr.RU team

First about the problem in general -

Sometimes, in order to unscrew a large nut without a suitable key, it is easier to adapt what is at hand for this than to run around the shops in search of a key. I myself use such a not tricky device that grabs and unscrews any pipes and large nuts. At the same time, all that is needed for him is a piece of a profile pipe of 30-40 centimeters and a motorcycle chain. Suitable for bicycles for small sizes. We weld the chain with one end to the pipe, and the other, tightly rounding the nut, we run it inward. We make a hall and the "clamp" is tightened, and the pipe acts as a lever. After the adjustable and gas wrench, this is the first tool, and the cheapest one is no where else.

Well, for a special case -

I can recommend the following.

The best of all-purpose tools for such interesting places This is a plumbing wrench with a self-clamping movable jaw. He's good at places like this.

You can bend the lips of a thin wrench (there are such in ZIP sets of motorcycles, bicycles and chainsaws) according to the example in such as shown in the photo below -

Under specific size nuts, located in a hard-to-reach place, you can make such a "grip" from a metal plate 4-5 mm thick. on the handle and with a collar.

Basically, on the clamping nuts of the mixers, the edges are 32.36 or 38 mm. Car enthusiasts may have a hub wrench of this size, it will also work well for this purpose. It looks like the picture below. In the same figure, I highlighted the key area, which can be taken as an idea homemade key- on a suitable tube, weld two pins that will abut against the corners of the nut faces, and make a knob from below.

In our time, few people already remember how to tighten the nuts correctly - since Soviet times, the gas-twisting industry has fallen into complete decline, so if, suddenly, someone takes up this business, you need to remember some rules.

What is a nut? This is a fastener in the form of a part with a threaded hole, forming a connection with a screw, bolt or stud. Nuts come in two thread types: metric or inch.

Nuts made of carbon unalloyed and alloyed steels are divided into strength class 4; 5; 6; 8; 9; 10; 12 - for nuts with a normal height equal to or greater than 0.8d; 04; 05 - for nuts with a nominal height of 0.5d to 0.8d. The strength class is indicated by a number, which, when multiplied by 100, gives the stress value from the test load in megapascals and indicates largest class the strength of the bolts with which they can form a connection. With this combination the bolt shank breaks before the threads, which makes it easy to detect the destruction of the fastener.

Despite the fact that the thread of a threaded connection has a helix angle much smaller than the friction angle, various vibrations, variable loads, violation of technology contribute to the disconnection (self-loosening) of threaded connection parts. To prevent this (to stop) apply special devices: locking, cottering, welding, soldering, riveting, applying glue to the thread, installing spring or lock washers, anchor nuts, etc.

For that so as not to break the stud or bolt(which will lead to the need for replacement), nuts in certain conditions must be tightened with a torque wrench. In the absence of the latter, it is recommended to use regular key and hands for tightening nuts (without using legs and wrench extensions).

You will say, think, tightened more - it will hold on tighter. No, they hold on, maybe they will, but we must not forget about the consequences. For example, if you are tightening the wheel bolts, you must remember that the discs are conical seats. And, if you overtighten the wheel bolts, then the thickness of the cone decreases, which, with a minimum thickness, can give vibration. Many roll discs, balance, but the vibration remains. If the vibration remains after rolling and balancing, you must come to terms with the fact that it’s time for the disk to landfill, and for yourself to conclude that no need to tighten bolts.

The choice of reliable tools is a serious task, which sooner or later everyone who is faced with installation work by profession or simply believes that any real man can do such things. Pay attention to the mechanical device for assembling and disassembling threaded connections with controlled torque - a wrench. And if “fresh” nuts and bolts can be completely unscrewed with an ordinary wrench, then in more difficult situations(for hard-to-reach connections or if there is rust) it is almost impossible to do without a wrench.

Main The difference between Russian impact wrenches and imported ones is that each model has its own landing size of the spindle square, and when using the tool, difficulties may arise with consumables. Imported tools have ¼ seat squares; 3/8; ½; ¾; 1; 11/2; 21/2; 31/2 (in inches), so there are no problems with interchangeable heads. The connecting thread of the imported tool is inch, and the Russian one, with the exception of IP-3115 and IP-3128, is metric, which is a disadvantage.

As a preventive measure, so that the thread does not rust, lubricate it with solid oil, graphite grease or engine oil. The lubricant will protect the thread from corrosion. for years.

Be that as it may, twisted the nut will have to be unscrewed sometime. If you cannot loosen a rusted nut, drop kerosene or a well-penetrating lubricant such as WD-40 into the visible part of the thread. Tap the nut lightly with a hammer. Wait a few minutes for the liquid to penetrate the threads and try to unscrew again. In order for the liquid to penetrate more into the thread, apply a rag moistened with kerosene or WD-40 for a longer time.

If you can’t unscrew it, try, on the contrary, tighten the nut. Often she succumbs to such a trick and is released..

Take a “minus” screwdriver with a steel rod along the entire handle, attach the sharp end of the screwdriver to the rusted bolt so that when you tap on the screwdriver with a hammer, it turns. It's almost a fail-safe way. If the bolt is large, use a chisel instead of a screwdriver.

By taking all precautions, it is possible to heat up a stubborn nut. It will expand and it will be easier to unscrew it. Do not let it cool, otherwise it will press the thread.

In order not to disrupt the edges, unscrew with ring wrenches, not open-end wrenches.