What is the reason why the blade of press brake can’t rise?

Generally, the press brake is equipped with more than 2 overflow valves, which are divided into two types: system and back pressure type.

If you can’t tell, remove and wash both, but you must first make sure whether the solenoid valve is energized.

Don’t tell me that the relays in the electrical cabinet don’t work when you step on and off, so don’t check the hydraulic part.