The reasonand solution of the arm loss of excavator 

Excavatorsoften have big and small problems, and it is really a headache! I don't know ifyou have encountered the excavator's arm. Why doexcavators lose their arms? How to solve the problem of arm failure?

What is anexcavator losing its arm

Excavatorarm also known as the boom, since the fall, fall pump and so on. Simply put,the arm is actually a performance of mining arm weakness, when the arm lift, inthe case of no control of the operating lever, the big arm or small arm willappear automatic fall phenomenon. 

When the excavator has arm failure, it willalso have different manifestations. The failure phenomenon can be roughlydivided into big arm failure, small arm failure, middle arm failure, normal hotcar arm failure and so on.

7 commoncauses of arm failure:

1. Armloss caused by hydraulic oil fault. Cold car normal hot car arm, is likely tobe hydraulic oil problems.

2. Thehydraulic cylinder of the excavator breaks down, especially the oil seal isdamaged or aging, which causes the leakage of the oil seal.

3. Distributingvalve valve hole blockage, spool wear, excessive spool clearance, distributionvalve main safety valve wear and damage, caused by the large and small armboom.

4. Whenthe oil seal of the safety overflow valve of the big and small arms is damaged,it will cause certain leakage and also lead to the phenomenon of arm loss.

5. Thedistribution pump seal is not good, also known as "unloading", thenneed to be the distribution pump sealing ring replacement.

6hydraulic pump proportional solenoid valve joint contact is not good, can alsocause the big arm arm phenomenon.

7. Severedrop arm (oil temperature 45 ℃ or so, 5 minutes buckettooth fell by more than 95 mm), is most likely the result of the main valvestuck.

Whatshould do if lose the arm of the excavator?

1. Checkthe operating environment temperature of the excavator, whether there isimproper selection of hydraulic oil model, and whether inferior hydraulic oilis used.

2. In caseof arm failure, the pressure of the moving arm can be reduced first, andcarefully observe whether the moving arm falls down quickly.

3. Checkwhether there is any fault in the hydraulic cylinder and oil seal of thecylinder. If the oil seal is defective, it will leak oil.

4. Afterreplacing the oil seal, if the arm is returned, check the distribution valveand the arm oil return valve, etc.

5. Checkwhether the working pressure and pilot pressure of the main hydraulic pump ofthe excavator meet the requirements.