With the development of hydraulic technology, hydraulic transmission system is very common in engineering machinery. From a technical point of view, any hydraulic transmission system should meet the requirements of reasonable design, simple structure, convenient use and high efficiency. Hydraulic system has a direct impact on the performance of the hydraulic engineering machinery, this paper on the use of hydraulic steering system common fault diagnosis and exclusion to talk about some understanding and practice.

(1) to the heavy

1) if the steering wheel is fast or slow to turn the steering wheel is heavy and the steering without pressure, it may be a low level of oil tank, oil viscosity is too large or valve body one-way valve failure. First check the oil level in the tank and hydraulic oil viscosity, if the oil level is lower than the standard height is added hydraulic oil, such as oil viscosity is too large should be replaced with proper viscosity of hydraulic oil, such as oil viscosity normal should disassemble steering device. If the valve body one-way valve ball is lost, into the new ball, if dirt stuck ball should be cleaned, if the check valve sealing strip and the steel ball contact undesirable application ball impact of the sealing is reliable.

2) if the slow to turn the steering wheel is light or the direction of the steering wheel, it may be caused by insufficient supply of hydraulic pump. In the oil level height and viscosity suitable premise should check the hydraulic pump is normal, such as low hydraulic pump supply small or pressure should be repaired or replaced.

3) if the no-load or light load to light and steering heavy for heavy load, may is valve block pressure relief valve below the working pressure of the overflow valve is dirt stuck or spring failure or damage to the sealing ring caused. Should first adjust the working pressure of the relief valve, the failure of the adjustment to the failure of the relief valve, such as spring failure, sealing ring damage should be renewed. ?

4) when the steering wheel is moved when the hydraulic cylinder is fixed and the irregular noise is emitted, it may be caused by the air or the leakage of the hydraulic cylinder in the steering system. Should open the tank cover to see if there is a bubble in the tank, if you have to check the oil tank in the leak, and then check the connections of the pipes are intact, and the exclusion of the air system. If the hydraulic cylinder is still time to move, should check the sealing condition of the piston, if necessary, replace the seal.

(2) steering failure

1) if it can not automatically return to the middle position and position the pressure drop, which may be the lack or break of the spring piece. At this point, the steering device can be decomposed to view the location of the spring, such as the spring piece is not due to the lack of flexibility, should be replaced, such as the spring piece should be replaced by the replacement of the new spring, is prohibited to use other parts replacement. ?

2) when the steering wheel is rotated, the pressure oscillation can be obviously increased and can not be rotated. It may be that the transmission pin of the steering gear is broken or deformed. At this point can be decomposed into the steering gear to see the transmission pin and the transmission rod, such as the transmission pin without a break to see whether the deformation, such as deformation should be replaced or corrected, the transmission rod opening such as a broken should be replaced by a new.

3) if the steering wheel rotation or the left and right sides may be the cause of the rotor and the transmission rod are in each other's position. At this point, the gear can be decomposed to the drive rod with the point of the teeth and the rotor spline hole with the teeth of the teeth can be.

4) if the mechanical deviation or turn the steering wheel cylinder or slow moving, may is the safety valve of the ball is dirt stuck or the damage of the sealing ring. Should be decomposed into the steering gear, cleaning the safety valve and replace the sealing ring.

(3) the steering wheel cannot be automatically returned to the

1) the steering wheel is turned on, the engine is running at low speed, if the rotation direction is large, the engine will be stalled and the steering wheel can be pushed up and down. If there is no gap between the two and the upper and lower, it is difficult to feel the steering column.

2) if the steering wheel is still not automatically back, it may be that the positioning of the spring piece break or transmission distortion, should be decomposed into the device after the examination, such as positioning spring deformation, elastic weakened or broken should be replaced, transmission pin deformation should be corrected or replaced, must not be replaced by other parts.

(4) steering gear oil spill

1) look at the traces of oil spills can be found. Such as the oil spill site is the tightness of the valve body, a swash plate, a stator and a rear cover combined surface can be used to check the hand joint bolt, if the bolts are loose and tighten no oil leakage fault in this. If the bolt is not loose can loosen all the bolts on the back cover, and then tighten the cross sequence, if not the oil spill description of the combined bolts did not tighten the specified order.

2) if the bolt according to the prescribed tightening sequence still leak, in conjunction with dirt or joint uneven surface or seal hardening, aging, damage to the surface. At that time, decomposition of steering gear. As with the surface dirt should be cleaned, check the limit bolt gasket, such as uneven should be removed or replaced.

(5) no human turn

1) first check the steering system of the connecting line has no rupture, joints are loose, if there is a leak in the pipeline rupture or joint loose, should replace the tubing, tighten the joint.

2) if the line is well, then turn to the hydraulic cylinder of a pipe joint loose, or so the steering wheel, see if there is no oil flow pipe flow, if there is no oil flow out of the pipe system is plugged, or the rotor with the stator with axial, radial clearance is greater than the allowable range, at this time should be removed and the steering gear. Detection of parts of the clearance and binding surface, such as exceeding the specified clearance should be polished chrome repair, such as surface minor scratches usable fine oilstone grinding, such as grooves or serious scratches should be replaced, such as the detection value within the scope of the provisions should be cleaning system oil gallery.

3) if the above examination is in good condition, the fault may be turned.