Hydraulic balance valve Excavator hydraulic cylinder valve core NFCD-LFN

Relief valve common troubleshooting methods

1) The discharge port of the pilot relief valve is blocked and not blocked, and the control oil has no pressure, so the system has no pressure, and the discharge port should be strictly sealed;

2) The remote control oil circuit connected by the remote control port of the relief valve is opened to control the oil return to the tank, so there is no pressure in the system. The remote control oil circuit should be checked and the oil circuit of the control oil return to the tank should be closed;

3) The damping hole of the pilot relief valve is blocked, resulting in no pressure in the system. The damping hole should be cleaned and the oil replaced;

4) The missing cone valve or steel ball or pressure regulating spring should be replaced in time;

5) The leak valve is stuck in the fully open position by dirt, and should be cleaned in time;

6) Hydraulic pump no pressure, should deal with hydraulic pump failure;

7) System components or pipeline damage and a large amount of oil leakage, should be checked in time to repair or replace.

3, the system pressure is too large, the adjustment is ineffective, should take corresponding measures according to the following reasons:

1) The control oil circuit from the main valve to the pilot valve is blocked, the pilot valve does not control the oil pressure, check the oil circuit to make it connected;

2) The inner oil drain port of the pilot valve is blocked by dirt, and the pilot valve cannot control the pressure. The inner oil discharge port of the pilot valve should be cleaned;

3) The damping hole wear is too large, the oil pressure balance at both ends of the main spool, the slide valve can not be opened, should be pressed into the stainless steel sheet such as the damping hole or the fine soft metal wire inserted into the hole, block part of the damping hole;

4) Oil contamination, the slide valve is stuck in the closed position.