Four typical hydraulic bending hydraulic bending system failure analysis, with troubleshooting methods

Views: 6     Author: DURMAPRESS     Publish Time: 2022-01-07      Origin: DURMAPRESS


Four typical hydraulic bending hydraulic bending system failure analysis, with troubleshooting methods

Hydraulic bending machine is a common industrial machinery equipment, widely used, but the fault is difficult to eliminate, today, Dalan hydraulic manufacturers on the special analysis of four typical bending machine hydraulic system failure, to help you in the work can be timely corresponding processing.

Fault one: the hydraulic system of hydraulic bending machine has no pressure

(1) Whether the electromagnetic coil of the proportional relief valve is energized, and whether the voltage of the proportional electromagnetic coil meets the requirements. For the above reasons, please check the related electrical reasons.

(2) Check whether the cartridge valve of the bending machine is jammed or whether the main spool is jammed, and the damping hole is blocked. If it is for the above reasons, please remove the overflow valve and clean it and reinstall it.

(3) Three-phase power supply phase modulation, resulting in motor inversion

Fault two: The slider turns fast and slow, and the time pause is too long.

(1) Check whether the oil level of the tank is too low, the filling port is not flooded, and the filling of the upper cavity of the oil cylinder is empty when fast moving, causing insufficient filling. For the above reasons, the oil in the tank of the bending machine can be added to more than 5mm above the filling port so that the filling hole is completely flooded.

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(2) Check whether the fast forward speed is too fast, causing insufficient liquid filling. For the above reasons, the fast forward speed can be reduced by modifying the hydraulic system parameters of the bending machine.

(3) Check whether the filling valve is fully opened. If oil pollution causes the spool of the filling valve to be inflexible and stuck, the filling is insufficient. The filling valve needs to be cleaned and reinstalled to make the spool flexible.

Fault three: slider return normal, fast forward normal, manual can not go down slowly, bending machine folding plate weak.

(1) Check whether the "two position four way" directional valve of the control liquid filling control oil circuit works normally. If so, the liquid filling valve is not closed, so that the upper cavity is connected with the liquid filling port of the oil tank, and the pressure cannot be built. The valve does not work properly because it is not energized or is jammed.

(2) Check whether the filling valve is jammed, if so, please clean the filling valve and reinstall it to make the spool flexible and free.

Fault four: the return speed of the slider is too slow and the return pressure is high.

This kind of fault is mainly the filling valve of the bending machine does not open, which is just the opposite of the logical relationship of the phenomenon of the above fault three, and can be dealt with by referring to the solution of the fault three.


CNC bending machine as a basic machinery, it is very common in each factory. Its maintenance measures if you can improve the efficiency of the work and the service life of the bending machine itself, we are going to introduce its maintenance content:

First, hydraulic oil circuit

1. The hydraulic oil used in CNC bending machine is ISO HM46 or MOBIL DTE25;

2. Check the oil level of the tank every week, including after the maintenance of the hydraulic system. If the oil level is lower than the oil window, add hydraulic oil;

3. The system oil temperature should be between 35℃ and 60℃, not more than 70℃, if too high will lead to deterioration and damage of oil quality and accessories.

4. Oil should be changed after the new bending machine works for 2000 hours, and oil should be changed after every 4000 ~ 6000 hours, and the oil tank should be cleaned every time the oil is changed.

Two, filter

1. CNC bending machine has related alarm or oil is not clean and other filter abnormalities, should be replaced;

2. Every time the oil is changed, the filter should be replaced or cleaned thoroughly;

3. The air filter on the fuel tank should be checked and cleaned every 3 months, preferably replaced every 1 year.

Three, hydraulic components

1. After the new CNC bending machine is used for a month, check whether the bending of each oil pipe is deformed. If there is any abnormality, it should be replaced.

2. Clean hydraulic parts (substrate, valve, motor, pump, oil pipe, etc.) every month to prevent dirt from entering the system, and do not use detergent.

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