A Komatsu excavator with a service life of 4000 hours has been working normally, but recently there was a sudden failure that the accelerator could not be added. After our investigation, we finally found that the cab line was damaged, and finally solved the problem. Today, let's share the problem that the accelerator of the excavator suddenly can't be added.
Why Komatsu excavator can't be throttled
(1) Check the oil circuit for blockage. Conduct routine treatment first, remove the oil pipe, remove the boom slide valve body, valve rod and relevant parts for cleaning, clean the oil passage and blow it dry with compressed air. From the surface phenomenon, it is mainly caused by the failure, damage, extrusion of the seal or the stretching of the sealing surface. Disassemble and check whether the cone valve of the main safety valve is stuck; Check the fitting clearance between the valve rod and the valve body. The normal fitting clearance shall be 0.005 ~ 0.025mm, and the repair limit shall be 0.04mm; Check the fit clearance between the main valve core and the main valve sleeve. The normal fit standard clearance is 0.010 ~ 0.018mm, and the repair limit is 0.03mm.
(2) Grind the two speed valve, remove burrs, and make the valve core move freely in the valve body without jamming. First check the side with slow travel speed, start with the combination valve, remove the two oil pipes on the pressure limiting valve, and block the oil outlet with plugs. There are many oil passages at the central swivel joint, which are easy to collude with each other. If the creeping phenomenon of hydraulic cylinder still exists after using for a period of time, check whether all seals are intact and assembled correctly. Generally speaking, this is not very easy to get, but I can give you some basic knowledge of excavators. I hope it will be useful to you.
(3) The hydraulic transmission systems used on excavators mainly include pilot control hydraulic system, slewing hydraulic system, traveling hydraulic system, working device hydraulic system, etc. it has the advantages of compact structure, flexible action, stable operation, convenient operation, etc. the hydraulic system uses hydraulic oil as the power transmission medium, which will leak due to the wear of internal components, accompanied by overheating, weak work and other faults.
The occurrence of hydraulic transmission fault is sudden and hidden, and involves many components, which brings certain difficulties to fault diagnosis and troubleshooting. Therefore, when maintaining the hydraulic system, we must understand its working principle and correctly analyze the cause of the fault to ensure the quality of maintenance. At this time, it is only necessary to check the boom spool valve, boom cylinder, boom oil pipe and its seals.
