How to deal with the failure caused by the high temperature in summer?

Causes of high temperature:

High temperature of rotary borewell drilling equipment is generally divided into gear box (splitter box) temperature is too high; Excessive temperature of hydraulic oil; Engine engine coolant temperature is too high (commonly known as high water temperature). The reason for the high temperature of gear box is relatively simple, the main reasons are the size and shape of bearing or gear and shell is not standard, the lubricating oil is not qualified or the oil level is not appropriate, etc.. Today I will focus on the excessive temperature of hydraulic oil and engine coolant. Let's analyze them separately.

Excessive hydraulic oil temperature:

First of all, the hydraulic oil temperature is too high, according to the hydraulic theory and recent maintenance experience, the main reason for the high temperature of hydraulic oil is too fast heat production and too slow heat dissipation. Hydraulic pump inlet pipeline and hydraulic oil tank seal is not strict, oil inlet filter block, hydraulic system pipeline is not smooth, hydraulic pump internal leakage will make the hydraulic oil produce a lot of heat so that the temperature of hydraulic oil due to heat generation and rapid rise.

The internal channel of hydraulic oil radiator is blocked, the external dust of the radiator is too large, the wind force is not enough, the hydraulic oil does not pass through the hydraulic oil radiator and other reasons can lead to the hydraulic oil due to slow heat dissipation and high temperature. The following are two cases of high oil temperature that we have dealt with:

Case A:

A user has been using a rotary excavator for three years, which has weak hydraulic response, slow speed and high hydraulic oil temperature. After entering the site, we found that the hydraulic pump is noisy when the excavator is running without load, and the two high-pressure pipes of the hydraulic pump feel vibration is very large. At the same time, the speed of the whole machine is slow. Obviously there's something wrong with the hydraulic pump.

The hydraulic pump of the hydraulic drilling rig was found to have been repaired. The original assemblers did not have the concept of Hitachi hydraulic pump matching bearing when replacing the bearing. The bearing gap was too large and there was no matching, leading to the abandonment of all accessories except the elevator and transfer box.

Replace the new parts according to the standard assembly test, hydraulic pump work smooth and smooth, the power and speed of the excavator are good. However, half an hour after the test, it was found that the temperature of the hydraulic oil had risen to 90℃. It seems that there are still problems. The hydraulic filter is a newly changed pure part. This indicates that there is no problem with the hydraulic tank and the intake line.

The surface of the hydraulic oil radiator is not dusty, the wind is strong enough, the wind duct is normal, the infrared thermometer temperature measurement found that the surface temperature of the hydraulic oil radiator is only 40℃, and the temperature of the hydraulic oil pump and hydraulic oil tank reached 92℃ and 90℃ respectively! Hydraulic oil radiator clogged?

Remove the radiator. No clogging is found in the radiator after inspection. Check the hydraulic pipeline and find that the one-way valve from the distribution valve to the hydraulic oil tank return pipe is not installed! This directly causes the hydraulic oil to go straight back to the tank without passing through the radiator. The oil must be too hot. So ordered a check valve installed test machine, machine back to normal.