1、 Is the structure and working principle of the rotary motor, engine and travel motor the same?
Basically the same, except that the traveling motor and engine have automatic braking devices, while the rotary motor does not. The common excavator structures for modern excavator repair include power unit, working device, slewing mechanism, control mechanism, transmission mechanism, walking mechanism and auxiliary facilities. For excavator repair, select a solid, flat and less dangerous environment for inspection and maintenance; The shovel teeth should be on the ground; Stop the engine and remove the key; The crawler shall be provided with safety measures of block type.
2、 When the excavator starts by operating the travel control lever that controls both tracks at the same time, the engine speed will drop instantaneously or even shut down. What is the reason?
This fault is common in excavator repair shop. This is mainly because there is a problem with the variable mechanism of the plunger pump. When the machine is idling, the plunger pump still has a large flow (unit: cubic meter per second).
3、 The walking oil motor and engine have just been repaired. When the accelerator is small, the crawler moves faster, but when the accelerator is large, it will not. What are the reasons and remedies?
This is because the valve plate has been grinded during maintenance and repair, and the grinding amount is too much, which makes the pressing force between the valve plate and the cylinder block plane insufficient. When the throttle is small, the oil pressure is small, and it is not easy to leak between the planes; When the throttle is large, the oil pressure increases and overflows between the planes, resulting in the tracks not moving when the throttle is large.
The remedy can be to add shims to the spring. If it is a butterfly spring, an additional butterfly spring can be added. For excavator repair, select a solid, flat and less dangerous environment for inspection and maintenance; The shovel teeth should be on the ground; Stop the engine and remove the key; The crawler shall be provided with safety measures of block type.
4、 What fault makes the excavator unable to travel in a straight line?
Generally, it is caused by the different oil pressure of the motor and engine on both sides. The side with high oil pressure will naturally go faster. During patrol inspection, two oil pressure gauges can be installed on the pressure taps of the traveling oil motors on both sides. If the pressure difference is large, the side with small pressure can be adjusted higher on the safety valve. If the pressure is the same on both sides, it is that the oil flow (in cubic meters per second) sent by the two plunger pumps is different (how to adjust the pump flow is specifically introduced in part 2). If type 3 and 5 machines can not go straight, patrol their straight-line control valve.
