Generally, it is caused by the different oil pressure entering the oil motor on both sides. The side with large oil pressure will naturally walk faster. During inspection, two oil pressure gauges can be installed on the pressure taps of the traveling oil motors on both sides respectively. If the pressure difference is large, the side with low pressure can be adjusted higher on the safety valve. If the pressure is the same on both sides, the oil flow sent by the two plunger pumps is different (how to adjust the pump flow is specially introduced in part 2). If type 3 and 5 machines cannot go straight, check their straight-line control valve.
Why can't the excavator stop on the slope?
Generally, the excavator can stop on the slope, because the walking pump of the excavator is equipped with a braking device, as long as it does not supply liquid
When the pressure motor supplies oil, the braking device plays the role of braking, and a pair of reciprocating valves are installed in two motor circuits in the system. Before the hydraulic oil p enters the traveling motor, one path of oil enters the a end of the reciprocating valve first to shift the reciprocating valve to B; One path of pressure oil p reaches the brake spool valve through the reciprocating valve, and the brake spool valve shifts to the spring direction to make the hydraulic oil to the motor braking device, and the motor starts to rotate. The brake device is also released, which is almost synchronous. When the oil supply to the motor stops, the reciprocating valve and brake valve will reset automatically, the motor will brake at the same time, and the reciprocating valve will cut off the flow of oil in the pipeline. Since the oil cannot flow, the reciprocating valve also acts as a brake. If the excavator cannot stop on the slope, be sure to check the leakage of the reciprocating valve.
Why does pca00-3 excavator have no quick stop?
The control oil of the variable speed spool valve comes from the control pump. There is a solenoid switch to control the speed in the cab. The control oil can reach the variable speed spool valve only through the solenoid valve controlled by this switch. If the solenoid valve is broken, it cannot change speed. When the fast gear is opened, the 2-position 4-way solenoid valve moves to the right, the control oil reaches the lower end of the slide valve through the solenoid valve, the slide valve moves up, and the high-pressure oil entering the upper chamber of the servo valve is cut off. At the same time, the control oil from the solenoid valve also enters the lower chamber of the servo valve, pushing the servo valve piston up to make the Mada variable.
Why can't the rotary motor of the rotary table rotate?
From Komatsu's type 3 to type 6 excavators, the turntable is equipped with parking brake device. If the brake solenoid valve fails or its control circuit fails, the motor brake device will not be opened.
If the rotary table swing variable speed brake solenoid valve is broken. What are the emergency measures?
The main function of the solenoid valve is to move the 2-position 3-way valve left and right, so as to cut off or connect the control oil circuit. We can connect hose a directly to the connector of hose B. for the time being, the motor can rotate without going through the solenoid valve.
When the rotary table rotates, it is difficult to stop at the position to stop. What is the reason?
This is because the locking function of the swing motor has deteriorated.
Is the structure and working principle of the slewing motor and the traveling motor the same?
It's basically the same, except that the travel motor has an automatic braking device, while the swing motor does not.
What does the rotary table stop on?
When the oil supply to the motor is stopped, the inlet and outlet oil circuits of the motor are sealed by the distribution valve. At this time, the motor cannot rotate on either side. Only when the two overload valves are faulty or the pressure is adjusted too low, the hydraulic oil will overflow in the overload valve and the motor will fail to stop.
