Chinese chainsaw. Carburetor repair. Carburetor adjustment.
Spare parts Powerful Chinese chainsaw Hunter analog Husqvarna 365
.
Carburetor repair
.
Start the chainsaw and let it run for about 10 minutes.
Place the Husqvarna 365 chainsaw on a level surface with the saw blade facing away from you and with both bar and chain in contact with the surface.
Find the maximum idle speed by slowly turning the low speed jet clockwise and counterclockwise.
When the maximum number of revolutions is found, turn the jet L counterclockwise 1/8. 1/4 turn.
Fine adjustment of idle speed using screw T
The idle speed is set using the screw marked T.
If adjustment is required, the idle screw T should be turned clockwise until the chain begins to rotate.
Then turn the screw counterclockwise until the chain stops.
The correct number of revolutions is considered to be the one at which the chain saw engine runs smoothly in all positions with a sufficient margin up to the number of revolutions at which the chain begins to rotate.
High speed jet H
The high-speed H jet regulates the power and speed of the Husqvarna 372, 365 XP chainsaw.
Specifications
The actual technical characteristics of the Chinese Husqvarna differ significantly from the original model. While browsing online stores, we found a lot of possible characteristics with different meanings. It turns out that finding out the real parameters is not so easy. However, in order to write this article, we had to personally visit a couple of dozen stores to find the Chinese Husqvarna 365 XP and find out the characteristics declared by the Chinese. Here's what we found out:
- Max Cutting Diameter: 450 mm;
- Rated Output Power: 2500 W;
- No-Load speed: 3000 r/min.
No matter how funny it may sound, under these parameters there is a simple inscription - Made in Sweden. Although at the very top of the sticker is Husqvarna 365 XP. The letters XP, as far as we know, indicate a fake!
Deciphering the names of the characteristics, we conclude that the maximum tire length is 450 mm. The power of the chainsaw engine is 2.5 kW. Rotation speed without load is 3000 rpm.
Let's compare the technical specifications with the original. The engine power of a real Husqvarna is 3.4 kW, which is 0.9 kW more. The maximum tire length is 700 mm, which is 250 mm longer. The crankshaft rotation speed at idle is 2700. As you can see, the original is ahead of the fake in absolutely all characteristics.
Today, the cost of a chainsaw, according to official data from the company’s website, is 35,990 rubles. The price for a fake varies from 8,000 to 14,000 rubles (this is how much they ask, in fact the price tag should be no more than 6,000 rubles).
HUSQVARNA
Technical specifications Husqvarna 372 XP
Engine's type. Gasoline Cylinder displacement, cubic cm, 70.7 cm3 Maximum power, kW. 3.9 kW (9600 rpm) Rated power at operating speeds, hp 5.3 hp (9600 rpm) Idle speed. 2700 rpm Spark plug. Champion RCJ7Y 5776166-02 (61141), Husqvarna HQT-1 5774840-01 (63893), NGK BPMR7A Interelectrode gap. 0.5 mm Fuel tank capacity 0.77 l Torque, max. 4.3 Nm / 6600 rpm Chain lubrication tank capacity. 0.4 L Lubrication circuit pump type. Adjustable flow Chain pitch. 3/8 inch chain thickness. 1.5 mm / 0.058 in. Bar length included. 45 cm / 18 inches Recommended bar length, min-max 38-71cm / 15-28 inches Chain rotation speed to maximum. it turns out. 21.4 m/s Equivalent vibration level, front/rear handle. 3.5 / 4.0 m/s2 Guaranteed sound power, dB (A). 115 Weight (without cutting equipment), kg. 6.1 kg
A chainsaw is needed in construction, gardening, and landscaping - its presence greatly simplifies the performance of a number of wood processing tasks. The main component of this tool is the engine, the operation of which largely depends on the condition and settings of the carburetor. This is where the fuel mixture is prepared. This means that if the saw does not start, stalls, or does not provide the required power, it is likely that the reason for this is improper operation of the carburetor. Fortunately, in many cases you can deal with this on your own. Only for this you need to know and understand the structure and operating principle of this unit and, of course, the chainsaw itself.
Properties and features of alternative applications
The operating time of the tool in operating modes is not limited, with the exception of short breaks for refueling and routine maintenance.
In private and farm households, the capabilities of the saw are used:
- for large-scale work on the procurement of wood fuel;
- construction of wooden log houses for residential and ancillary facilities;
- landfills and sawing of old trees.
Thanks to its versatility and wide functionality, the Husqvarna 365 saw is included in the standard equipment of emergency rescue units of the Ministry of Emergency Situations. The wear resistance of carbide chains allows the tool to be used for sawing concrete and non-massive metal structures.
How does a chainsaw carburetor work?
The main purpose of a carburetor is to mix fuel with air in the required proportions. If the latter are violated, this almost instantly affects the operation of the engine.
Chainsaw carburetor Stihl MS 181 C BE
Chainsaw carburetors may differ in design. However, their basic elements and operating principle remain approximately the same.
Carburetor design:
- The basis
This is a wind tunnel, across which there is an air damper - with its help the intensity of the air supply is regulated.
This part is where the base tube narrows - here the air flow speed increases, i.e. air is always supplied to the carburetor under some pressure.
In this area, the fuel comes into contact with the air flow. Fuel enters the atomizer from the float chamber through a nozzle (dispenser).
- Float chamber
This is a container that allows you to keep the fuel mixture in a stable state.
Chainsaw carburetor design diagram
A chainsaw carburetor works according to the following principle:
- when the engine starts, the main damper opens and a stream of air is supplied into the air channel at a certain speed;
- the speed of the air flow, as well as the level of the float in the chamber, are regulated by the position of the damper, namely due to the difference in pressure in the float chamber and the air channel;
- fuel from the float chamber is sucked into the nozzle, and from there into the diffuser;
- passing through the diffuser, the air captures the fuel entering there;
- the resulting mixture is fed into the cylinder cavities through the intake channels.
The principle of operation of a chainsaw carburetor
The pressure in the float chamber is approximately equal to atmospheric pressure, but a vacuum occurs in the air channels of the carburetor when the chainsaw engine starts. Opening the damper increases the air supply intensity. As a result, more fuel enters the carburetor, and the number of engine revolutions increases.
Advantages and disadvantages of the Walbro HD 6B carburetor
Undoubtedly, this carburetor has many advantages. Here are some of them:
- High-quality assembly of the carburetor and its high reliability. With proper and timely carburetor care, your chainsaw can serve you for many years. Numerous reviews on the Internet only confirm this.
- Convenient carburetor design. The membrane in the pulse chamber allows you to pump fuel when working in any position of the chainsaw, be it horizontal, vertical or side cutting. This is very convenient, unlike chainsaws with float-type carburetors, where fuel enters the carburetor by gravity and when cutting sideways the saw simply stalls.
Of the minuses, I would like to note the absence of a primer on the carburetor or a heating system for it. In Russia, it is often necessary to operate a saw in the winter season. In severe frosts, starting problems sometimes occur.
When choosing a carburetor, there is a chance of running into a fake. To avoid buying a counterfeit, before purchasing, watch the following video, which shows in detail what the factory packaging and the Zama carburetor itself for the Husqvarna 365 chainsaw look like.
Why is primary adjustment needed?
During the first hours of operation, the 2-stroke chainsaw engine requires running-in, on which the quality of its further operation depends. During the running-in process, the carburetor is initially adjusted - the optimal parameters for preparing and supplying the fuel mixture are established.
Initial running-in of the chainsaw: working with thin material
Most modern chainsaws are sold adjusted. However, it doesn’t hurt to check the quality of the factory settings - in the end, it’s you who will have to work with the tool.
When starting up for the first time, the chainsaw should operate in a gentle mode. Therefore, for several hours after start, it is recommended not to overload the engine and cut only small branches and trunks up to 10 cm thick.
Simple rules will help you insure against malfunctions of the chainsaw carburetor:
- Always mix gasoline and oil according to the manufacturer's instructions.
Proportions of the fuel mixture for a chainsaw engine
The chainsaw must start correctly, ensure a stable rotation speed of the sprocket and a smooth increase/decrease in power. There should be no extraneous knocks, pops or noises when the engine is running.
Professional hand chainsaw at work
The main thing during the initial running-in of the tool is to ensure that the fuel consumption corresponds to the power used, i.e. in practice, the saw should not go out, “sneeze”, smoke or run jerkily.
Read also: Gradation of circuit breakers by current
Chainsaw malfunctions and how to fix them
Owners of the Husqvarna 142 model often encounter typical breakdowns caused by improper use of garden tools or simple wear of its parts.
These malfunctions include:
- the chainsaw does not start - the cause of this breakdown lies in the spark plug being flooded. To be able to start the saw motor, you need to remove, wash and dry the spark plug. After this, you need to blow out the cylinder by sharply pulling the starter cable several times with the spark plug turned out. After this, you need to screw in the spark plug and start the engine of the garden tool;
- increased vibration during operation of the saw - repair of this breakdown is carried out by cleaning or replacing the muffler. You will also need to inspect the springs of the anti-vibration system. If necessary, sagging parts must be replaced;
- shooting sounds - if loud popping noises are heard during operation of the Husqvarna model, then the causes of the breakdown should be sought in the carburetor or muffler. The operator will first need to adjust the carburetor. After this, you need to remove and wash the muffler;
- leakage of oil to lubricate the chain - to eliminate this breakdown, you need to check the condition of the oil pump and pipes. The faulty part will need to be replaced.
To avoid further breakdowns of the Husqvarna 142 chainsaw, you need to use high-quality gasoline and oil to refuel it. This will help prevent increased wear of parts and protect model components from overheating.
The carburetor is one of the important mechanical components that make up a chainsaw. Its tasks are to mix fuel with air and supply the resulting composition to the engine. But during the operation of the chainsaw, situations arise when adjusting the Husqvarna carburetor becomes necessary. Depending on the reasons, the carburetor of the chainsaw model 142 and other series is adjusted to prevent the following situations:
- the presence of interruptions in the operation of the motor, accompanied by its shutdown;
- excessive fuel consumption during operation.
Since the carburetor affects the quality of the fuel, in the first case, the need to adjust the carburetor of the saw 137 or other professional series, such as Husqvarna 240 or 260, implies an influence on the sufficient amount of combustible raw material entering the carburetor for mixing with the air mass. It is known that maximum performance is possible only with a certain ratio of these substances. The second point in adjusting the carburetor mixer of a chainsaw is caused by a lack of incoming air, which causes the injected gasoline to fail to burn and be released in the form of thick smoke. A timely change of parameters with your own hands to reduce the amount of injected fuel will allow you to significantly faster reduce the consumption of this product.
Do-it-yourself repairs will save not only the budget, but also the time spent on transportation and queues in the workshop. The same applies to replacing various spare parts in gas-powered tools, such as a chain for a chainsaw or a universal trimmer head for a brush cutter, or oils for electric drive products.
How to recognize carburetor failures?
Typical carburetor malfunctions are easy to recognize. They are expressed in the fact that the chainsaw engine starts and immediately stalls or shows no signs of life at all. Well, or it consumes fuel with all its might, producing clouds of black smoke and aggressive vibrations instead of the required power.
Operation diagram of a chainsaw carburetor
Carburetor settings may be affected by:
- lack of fixation of the adjusting screws;
Chainsaw adjustment screws
New CPG chainsaw Husqvarna 365
Chainsaw air filter with nylon insert
Any problems found should be corrected immediately. But how can you determine that the problem is in the carburetor? To do this, watch how your tool works.
Typical signs that the carburetor settings are off include:
- Unstable motor operation
As a rule, the reason for this is the use of the wrong (lean) fuel mixture.
- Excessive fuel consumption
It is expressed in an increased release of exhaust exhaust, which turns black. This means that fuel is not completely consumed, i.e. the mixture is oversaturated.
The carburetor is adjusted correctly - the saw starts the first time
- Arbitrary changes in engine power
May be associated with damage to the fastening of the adjusting screws or the protective cap.
- Increased fuel consumption accompanied by vibrations and pops
This indicates critical wear of the piston group, so adjusting the carburetor will only postpone major repairs for some time.
- Sneezing and engine jerking
This picture is observed when the carburetor channels are clogged or its filters are faulty. In this case, adjustment should be carried out only after thoroughly washing the unit.
Chainsaw fuel filter
Despite the fact that the carburetor is the most complex part of the engine, you should not be upset if you detect malfunctions in its operation. Instead, you need to arm yourself with some tools, a design diagram of the unit and sound logic.
Chainsaw carburetor being repaired
What to do if the chainsaw continues to not start?
If the initial inspection did not yield anything or the defects were eliminated during the search process, but the chainsaw still does not start, then you need to look for more serious reasons. It is best to identify and repair such breakdowns at a service center. However, if you have experience, you can find and eliminate them yourself. What to diagnose and check?
- Compression in the cylinder;
- Compression in the crankcase;
- Carburetor operation.
In the first case, checking the compression in the cylinder will allow you to find out the condition of the cylinder-piston group (CPG) of a chainsaw that does not want to start when cold. To do this you need a compression gauge. The device is screwed into place of the spark plug and the engine is started idle. Measuring the readings allows you to judge the condition of the CPG. In the absence of a compression gauge, you can determine the compression in the cylinder offhand as follows:
- Place your finger on the spark plug hole;
- Try to start the chainsaw engine.
By placing your finger on the spark plug hole and pulling the starter, you can check the compression in the cylinder
If you feel that your finger is being pulled strongly into the spark plug channel, then everything is in order with compression. The absence of vacuum in the chamber indicates a malfunction. The cylinder-piston group needs a more detailed inspection, which will give an idea of the condition of the piston and cylinder, piston rings and bearings.
A chainsaw may not start when cold due to a lack of compression in the engine crankcase. The main reason for this is damage to the gasket located between the cylinder and the crankcase. It is quite easy to detect a lack of compression:
- Disconnect the upper tube from the carburetor;
- Pour gasoline into a regular cork;
- We immerse the removed tube in the fuel;
- We pull the starter several times.
Do-it-yourself disassembly: nothing complicated
First of all, you need to prepare a place for disassembly. This could be a workbench or a regular table. In addition, you need a rectangular piece of fabric or cardboard - on it you will carefully fold the carburetor parts. And finally, a tool: for disassembly you will need a set of open-end wrenches and screwdrivers, a special cleaning compound and an ultrasonic cavitation bath.
Chainsaw carburetor repair tool
First, you will have to dismantle the chainsaw carburetor. This is done in this order:
- To get to the carburetor, you need to remove the top cover of the chainsaw, secured with three bolts.
Removing the carburetor cover
Removing the fuel hose and drive rod
Removing the throttle cable
After removing the gasoline hose, the carburetor is ready for disassembly
The carburetor must be disassembled in the order prescribed by the design and functional solutions of its elements. The parts of the chainsaw carburetor do not differ in size, so you need to fold them carefully and in order, trying not to lose anything.
Disassembling a chainsaw carburetor in the photo
After disassembly, it is necessary to carry out troubleshooting and replace damaged or worn parts. Next, the entire set should be washed with a special product, dried and wiped with a dry lint-free cloth. The jets and tubes of the assembly must be purged with compressed air, or, in order to more thoroughly remove formations on their internal surfaces, they must be treated with ultrasound beforehand.
User manual
Here is the original instruction manual for the Husqvarna 365 petrol chainsaw: Your browser does not support framesDownload the Husqvarna 365 chainsaw operating manual
The operating manual introduces the new chainsaw owner to all the features of the tool.
Husqvarna chainsaw device
The information offered is divided into sections:
- Design and sequential assembly of gas-powered tools.
- Safety requirements.
- What is included in the delivery kit for the chainsaw.
- Technical characteristics of the Husqvarna 365 chain saw.
- How and what to cut correctly.
- How to prepare a Husqvarna 365 chainsaw for use.
- Break-in is an effective way to increase the service life of gas-powered tools.
- THAT.
- Problems and causes of their occurrence.
Basic safety rules:
- Work in overalls, using glasses, gloves, etc.
- Refuel the chainsaw away from the work area.
- Do not smoke near the instrument.
- Saw with the entire bar, not the end.
- Do not disassemble the saw while it is running.
- Do not work in enclosed spaces.
- Remove bystanders from the work area.
- Working with a faulty chainsaw is prohibited.
First start
Basic steps before using a chainsaw:
- Installation and tensioning of cutting equipment.
- Refueling with freshly prepared fuel (for 1 liter of unleaded gasoline AI-92, take 100 ml of original 2T oil for Husqvarna).
- Filling the oil tank with chain lube.
- Tightening fasteners.
- Starting the chainsaw.
- Control check: oil supply to the chain; idle speed; brake.
- Break-in period. Break-in time is 10 hours. The chainsaw is operated at half power.
Maintenance
- After each use, the Husqvarna 365 needs to be cleaned:
- Sharpening the cutting chain, replacing if necessary.
- Mechanism lubrication.
- Adjustment and adjustment work.
- Maintenance.
Basic problems and troubleshooting
The chain saw does not start:
- the fuel has run out, is of low quality, there is water in the fuel;
- the spark plug is smoked, wet, burnt out;
- the carburetor is overflowing with fuel, is dirty or has lost its settings;
- the ignition does not respond, is not adjusted, there is no spark;
- high-voltage cable break;
- the piston is jammed, the piston is worn out;
- The air filter is dirty.
Husqvarna chainsaw stalls under load:
- filter cleaning required;
- the carburetor needs to be adjusted;
- replace the spark plug;
- replace the fuel mixture.
Carburetor tuning: main points
Reassembly of the carburetor is carried out only after complete cleaning, drying and blowing with compressed air. However, do not forget that some gaskets and seals, even if there is no damage, must be replaced.
You can begin adjusting the carburetor if it is correctly troubleshooted, of high quality assembly and flawless re-installation on the engine.
Principles of carburetor tuning:
- screws H and L adjust the ratio of air and fuel mixture, i.e. throttle position. Tightening the screws clockwise leads to a lean mixture and the engine switches to low speeds. When unscrewing (counterclockwise), the mixture becomes richer and the engine speed increases;
- screw T is responsible for adjusting the idle speed: turning it clockwise increases their number, counterclockwise - decreases it;
- The screws are adjusted in LHT order.
Chainsaw carburetor calibration
The general adjustment algorithm looks something like this:
- Initially, the highest idle speed is found by turning screw L and then returning ¼ turn counterclockwise. If the chain rotates at idle, turn screw T in the same direction until it stops completely.
- With the engine warm and running at full speed, turn screw H ¼ turn to the left, then let the engine run for 10 seconds and check the maximum speed using a tachometer. It must correspond to the number indicated in the instrument passport.
- After calibration with screws L and H, using screw T, the idle speed is adjusted. If everything is done correctly, the engine will operate evenly in all its positions.
Reminders for calibrating the carburetor on the chainsaw body
Upon completion of the adjustment, all that remains is to reinstall the chainsaw cover with the insulating gasket, after which you can begin the main work. If the settings are correct, the chainsaw engine will receive the optimal fuel mixture. This will ensure its normal efficiency, as well as overall comfort and safety of working with the tool.
Tools required for work
Before you start setting up the Husqvarna carburetor, you need to make sure you have all the tools that may be useful. To carry out this type of work yourself, you will need:
- screwdriver for adjusting screws (H) and (L), in specialized stores they have very high prices, so we recommend buying such screwdrivers as a set from Aliexpress; in our service we use such a set;
- electronic tachometer to determine crankshaft speed readings (with some experience, you can adjust by ear), in our tool repair service we use a high-quality and inexpensive analogue, which can be ordered on aliexpress using this link; there is also a cheaper option that copes with your task is to look at AliExpress;
- Phillips screwdriver , for adjusting screw (T);
- compressor with a blow gun for cleaning the saw before work.
A regular slotted screwdriver will not work for adjustment , since the adjustment screws on Husqvarna chainsaws can have a different cross-section. You will have to purchase a special one, this is a feature of repairing Husqvarna chainsaws; they did everything so that the saw could be repaired only in a specialized Husqvarna service center.
Detailed review of Husqvarna 365
In terms of external design features, this is a completely understandable chainsaw, which is used by thousands of workers around the world and shows unpretentiousness in repairs and a number of other advantages. Swedish engineers spend a long time on each model, so the 365 is truly a professional in its class with all the necessary components (hand guards, chain catcher, decompression valve, handle and much more).
Advantages
Of course, a chainsaw has more positive characteristics and features, which include:
- a unique heating system for the handles allows you to work in winter without discomfort;
- modern cooling system and a new system with centrifugal air purification;
- engine crankcase made of magnesium aluminum alloy;
- conveniently shaped handles for a secure, confident grip on the chainsaw;
- parts of the crank mechanism are created manually from high-grade forged steel;
- On the side of the cover there is a chain tensioning mechanism, it is conveniently located and helps to quickly make adjustments.
It is impossible not to note the new starter with a unique Smart Start system. According to the manufacturer, this system provides 2 times faster start and start of the chainsaw. A particularly relevant system for long-term use.
Additionally, we note the Air Injection air purification system, which has a centrifugal action and helps to increase the life of the chainsaw and the life of the air intake filter.
Other characteristics
Very often, the Swedish chainsaw is used far outside the city, so the 365 model is equipped with everything necessary for long-term unhindered work. For example, the fuel tank is increased to 770 grams, while the oil tank has a capacity of 420 ml. Despite the above characteristics regarding the tire used, other models can be installed; a tire up to 70 cm long is suitable. In the standard kit you can find a 45 cm long tire with a chain having a link thickness of 0.058.
The chain and bar have a long life due to cooling through lubrication in the form of self-supply of oil to the working area. Oil is also automatically supplied from the oil tank. This is possible thanks to a modern oil pump. A special feature of the tank is the ability to regulate its performance, which in turn saves the owner up to 50% of fuel and lubricants.
Where to use the Husqvarna 365 chainsaw?
Initially, the Swedish brand created characteristics for the Husqvarna 365 chainsaw that allowed it to work in difficult conditions and provide high productivity. Today it is a reliable assistant even for working all day long. You can also work with the equipment all year round; for winter, heated handles are installed; in summer, the chainsaw does not overheat and works well at high temperatures.
If you plan to operate in extreme cold, we recommend that you pay attention to an additional option - a carburetor heating system. This way it will not freeze and will supply fuel unhindered.
About Husqvarna 365, some reviews say that the model can work in temperatures as low as -40 degrees.
Husqvarna 365 is also great for other tasks:
- firewood preparation;
- gardening;
- pruning trees, branches.
Husqvarna-236
This model replaced the much-loved 137.
Having slightly less power (1.4 kW), it added 100 g in weight, gained a 40-centimeter saw bar and, most importantly, a new engine, 20% more economical than its predecessor, with higher torque and a wider speed range, which did the job with this saw it is even more comfortable and has slightly expanded the range of its applications.
True, its cost has increased somewhat and today amounts to almost 11 thousand rubles, but if you recalculate to the current dollar exchange rate (and these saws are produced in Sweden and the USA), then everything will fall into place.
Headset
The cutting unit is included in the category of replaceable equipment. The standard kit consists of a proprietary 18-inch guide bar and a wear-resistant chain model H42, with a standard pitch of 3/8 inches.
The bar and chain are lubricated and cooled by the automatic supply of oil to the working area, liquid that is taken from a 420 ml oil tank located in the housing. The use of an oil pump with adjustable performance allows you to consume oil with 50% savings.
The lubrication system is designed for a certain density of chain oil. The use of substitutes can seriously affect the performance and other operating parameters of the oil pump, and the service life of the headset.
The lineup
The Husqvarna 365 chainsaw also has letters in its name – SP (i.e. special). This is the same model, although the presence of letters at the end of the name is often perceived as a variation of the main unit.
In fact, the modification is Husqvarna 365 h, which differs even in appearance:
Chainsaw Husqvarna 365H
- high handles allow you to work without bending, due to the fact that they have a built-in tank and controls;
- The handles are also equipped with a rotation function, which makes it possible to achieve the desired position of the tire in space.
365 h is designed specifically for felling trees in deep snow conditions. Otherwise, the technical features of this version are the same as the 365 SP. The downside of the modified version is the cost - it is 2 times higher than the basic one.
Purpose of Husqvarna 365 and where it can be used
Husqvarna 365 was developed for use in difficult conditions, throughout the working day. This means that it can be used to solve any, even the most complex problems, anywhere where it is needed. The saw is well adapted for work in winter, when the temperature drops quite low, and at the same time performs well when working in the heat. Additionally, the 365 18 Husqvarna chainsaw can be equipped with a heated carburetor in order to avoid icing when using the saw in severe frosts. This is relevant for the northern regions of our country, where, due to the lack of roads, deforestation work is carried out mainly in winter.
The saw is actively used for working in the garden and for preparing large volumes of firewood, which is very important for those who live in rural areas.
Another area of application for this chainsaw model is emergency rescue work. Together with special saw chains with Pobedit tips, this saw turns into a universal tool that can cut not only wood, but also metal parts or concrete structures, for example, locks, rowlocks, awnings, fragments of concrete buildings, and at the same time the chain retains its function for a long time performance.