Gur "Kamaz": device, repair, scheme

Hydraulic power steering, or GUR - just a necessity for heavy and heavy vehicles. And if on cars many do without this helper, then try to turn the rudder "Kamaz" without it. Today, we all learn about the Gur "Kamaz": the arrangement of mechanisms, the principle of operation, and also talk about typical malfunctions and repairs.

The tasks that are solved by the GUR

The main purpose of the power steering is to make it as easy as possible to force the steering wheel in the event of various maneuvers at low speeds. Also the amplifier makes the impact on the steering wheel more palpable at high speed.

Device

What is the Kamaz GAM device? The mechanism consists of a distributor, hydraulic cylinder, hydraulic fluid, pump, and also from connectors and the electronic control unit.

The distributor is necessary for directing the flow of hydraulic fluids in the cavity of the system. The hydraulic cylinder solves the problem of converting hydraulic pressure into the mechanical work of rods and pistons. The fluid not only transfers the forces from the pump to the hydraulic cylinder, but also lubricates friction nodes and parts. Its pump is designed to maintain the necessary pressure at all times. It also promotes the circulation of liquids. A connector or a tube of the "Kamaza" GUR is used to unite all the elements of this design. And finally, the electronic unit. It directs and regulates the operation of the amplifier.

The device of a typical GUR

What is the GUR ("Kamaz") device? Often the actuators are presented in a single body with the steering system. Such an amplifier can be called integral. As a hydraulic fluid, various oils such as ATF are used. These are usually poured into FRGG.

How does he work? The "Kamaza" GUR is very simple. When the steering wheel rotates, the rotary or axial-piston pump, which is driven by the crankshaft belt, starts to pump the oil out of the reservoir, and then pushes the hydraulic fluid under high pressure into the spool valve. The latter tracks the force that is attached to the steering wheel and assists in turning the wheels. To do this, use a special tracking device. Often such an element in typical systems is torsion. It is built into the section of the steering shafts.

If the car is standing or moving in a straight trajectory, then there is no effort on the shaft of the steering system. Accordingly, the torsion bar is open, and the valves of the distributor are closed. The oil is then discarded in the tank. When the steering turn is fixed, the torsion bar turns. The valve releases the channels, and the working fluid is sent to the actuator.

If the system is equipped with a rack-and-pinion mechanism, then the liquid is fed directly into the rack body. When the steering wheel is turned to the stop, then safety valves are switched on, which in time relieve pressure and protect the mechanical components from possible damage.

Gur "Kamaz-5320"

The device is practically no different from the standard amplifier. Here, too, there is a distributor, a reducer, and also a hydraulic cylinder integrated in the steering.

The operation of this unit is possible only with a constant movement of the working fluid. This ensures a low pump load. The pressure in the system is 8000 kPa. The power cylinder is integrated into the crankcase of the steering gear. As a control valve, a spool valve is used, equipped with a jet plunger system and centering springs. They create a sense of resistance forces at the time of turning the wheels.

Gur "Kamaz-4310"

This node is almost the same here as in the model 5320. The principle of operation of the Kamaz-4310 GUR, the device and design of this node are practically the same. The main difference is only in the strengthening of some parts, as well as in the modified fastening of the steering bipod. Here bolts, cotter pins and other fasteners are now replaced with nuts with lock washers.

Hydraulic pump

The GUR pump is mounted in the collapse of the cylinder block. On the "Kamaz" is used a drive gear type, but the pump refers to the blade type. It has a double action. For one complete revolution, it performs two cycles of injection and suction.

Device

What is the device pump GUR "Kamaz"? This unit consists of parts of the body, stator and rotor, which is equipped with blades. Also in the design, a shaft with bearings and gear for the drive is used. In addition to the pump, there is a distribution disk in the structure, as well as bypass and safety valves. Still there is a tank, a filter and a collector.

The housing parts, the stator, and the cover are connected and fastened using four bolts. The body has a cavity where the sucked in oil enters. At the end of it you can find two holes of oval shape. On them hydraulic fluid is supplied to the rotor. In the cover there is a special bore for the distribution disk, holes for the valves, and a channel. From the bottom there is a calibration hole in the cover.

The rotor is mounted in the stator with the help of splines. In the grooves it is placed blades. The shaft can be rotated by means of ball bearings. The liquid is directed to the blades using a distributor disk. With the help of a spring, the disk is pressed tightly against the stator and to the rotor. Then, the bypass valve limits the operation of the pump, and the safety element restrains the pressure created by the pump.

There is also a special tank for liquid. It is fixed to the pump casing. In the tank there is a special strainer. Here you can find both a priming filter and a safety valve.

How does the pump work?

When the rotor blades rotate, they are pressed against the stator by inertia. In the blades, which coincide with the holes in the body, as well as the distribution disk, liquid is supplied. Then it is pumped with blades into the narrower part between the rotor and the stator. When the working cavities coincide with the holes in the disc, the liquid will exit through the holes behind the disc. And from there, under high pressure, it will go down the lower valve to the system. Oil from the cavity behind the disc falls on the rotor blades and even more presses them to the stator surface.

Injection and suction work at once in two places. When the rotational speed of the rotor increases, the oil from the cavity behind the disc does not pass through the calibration hole. So pressure builds up, opens the bypass valve. A little liquid through the collector gets back into the suction cavity. So the productivity of the mechanism decreases.

About the most characteristic breakdowns that are inherent in the GUR

I must say that the failures of the "Kamaz" GUR are rare. With high-quality operation and timely maintenance of this unit, you can even forget about frequent adjustments. However, even if infrequently, you can read about problems with the amplifier.

If it were not for Russian winter, then GUR would have worked all the time the truck was in operation. However, winter frosts, terrible roads often lead to too early deterioration of the mechanisms of the GUR. Usually all breakdowns can be divided into problems with the mechanical part and hydraulic faults.

Both mechanical and hydraulic problems can appear in any part of the site. Like any hydraulic system, the amplifier does not tolerate cold. Especially he does not like too drastic changes. The same pump pumps quite a lot of pressure. Consequently, if the viscosity of the working oil suddenly increases, it can squeeze out oil seals.

In addition, it is not always possible to comply with even the most simple rules for safe use. Often drivers leave cars with turned wheels in great frosts. After the engine is started, the pressure will grow only on one side. As a result, squeeze out the omentum. Also, very few people in accordance with the regulations replace the hydraulic fluid. And it can thicken with time. This leads to excessive pressure.

But this is winter, but what about summer? And here the problems appear mainly because of dust or dirt. It is enough only a very small depressurization of the system, and soon the repair of the Gur "Kamaza" will be required. Thus, with depressurization, rods and bushings wear out. The first immediately rust and increase the wear of the second. After a couple of hundred kilometers, the gaps between the stem and the bushing become more permissible. So, the steering rack will knock.

Observe the cleanliness and level of the working fluid

To avoid problems with the power steering, you need to keep clean. Dirty hydraulic fluid can significantly accelerate the wear of the pump and seals in the mechanics of the steering rack of the truck.

It is necessary to try to look for the level of oil in the tank. If the level is lower, the pump will run in the premature wear mode.

Symptoms of typical element faults

If you need to constantly align the car with the steering wheel, you should check that the steering wheel is free. If it is higher than necessary, you should adjust the stroke. Also, you need to make sure and check if parts of the screw pair have worn out.

In the event of air getting into the hydraulics, a foamed and turbid liquid can be seen in the reservoir. In this case, you need to rinse and pump systems. Also a filter must be replaced. In addition, one of the typical faults is a collector gasket that can wear out.

Repair and adjustments

Repair work is reduced to the replacement of worn parts or assemblies. All spare parts for the amplifier are manufactured and are in the schematics of assembly units. The parts can not be restored.

For adjustments it is necessary to have a special tool - a dynamometer, and to check the pressure you need a manometer.

So, we found out what the GAM "Kamaz" device has, faults, design and operation principle.