In the field of construction machinery, the purchase of used excavators has always been the focus of attention of A friends. In order to ensure the purchase of a good performance used excavator, Tiejia.com has already introduced the method of identifying a used machine through observation and a test run for the engine in a previous article. Today, we will delve into how to further identify the quality of a used excavator through a hydraulic system test run.

As one of the core components of the excavator, the performance of the hydraulic system is directly related to the overall efficiency and service life of the excavator. Therefore, the detection of the hydraulic system is particularly important in the trial process.

First of all, the trial movement is the first step of the hydraulic system test. This includes bulldozing shovels, walking, slewing action, and various actions of the bucket, bucket lever, moving arm. When trying the action, it is necessary to observe whether the operation of each component is smooth, whether there is any jamming or abnormal sound. For example, when trying the earth-moving shovel, it is necessary to check whether its lifting up and dropping down are in place, and whether there is any phenomenon of automatic descent after jacking up the whole machine. Meanwhile, when walking test, pay attention to whether the excavator has obvious running phenomenon. The test of slewing action needs to pay attention to its reaction speed and braking performance. For the bucket, bucket lever, moving arm action, although there is no strict standard for fast or slow, but too fast or too slow may indicate that there are problems with the hydraulic system.

Secondly, the sealing test is also an indispensable part of the hydraulic system trial. This can be done by stopping on a ramp to test the internal leakage of the travelling motor, and by jacking up the work unit and placing a heavy object to observe the change in cylinder travel. If there is a change in stroke of more than 10cm in half an hour, this may indicate that there is an internal leakage problem in the hydraulic system which needs to be dealt with promptly.

Finally, the pressure measurement is the most critical and professional steps in the hydraulic system test machine. This requires a uniform measurement of each action, pump pressure, pilot pressure, and return pressure. Insufficient pump pressure may lead to insufficient strength, insufficient pilot hydraulic pressure may lead to slow and weak action, while too much return pressure may lead to high oil temperature, and too little pressure may affect the normal work of the replenishment parts. Therefore, for non-professional used mobile phone assessment master, this step may be more difficult, but is still an important indicator to assess the performance of the hydraulic system of the used excavator.

In summary, through the hydraulic system test machine can comprehensively assess the quality of used excavators. Tiejia.com reminds the majority of A friends, when buying a used excavator, must carry out a detailed test machine test, in order to ensure the purchase of good performance, long service life of quality equipment. At the same time, it is also recommended that A friends choose a professional used mobile phone assessment agency for assessment, in order to obtain more accurate information about the performance of the equipment.