The Valve No. 19 serves as a critical safety mechanism for the folding arm’s hydraulic supply. Its primary function is to protect the system—specifically the hydraulic rotary coupling—from over-pressure in the event the arm collisions with a fixed object.
Functional Purpose
Impact Protection: Prevents catastrophic failure of the rotary coupling if the arm crashes.
System Stability: Ensures the arm remains rigid during the wrapping process.
Symptoms of Incorrect Adjustment
Calibration & Testing Procedure
To ensure the valve is functioning correctly, perform the following manual "Pull Test":
Manual Check: With the system pressurized, attempt to pull the folding arm firmly by hand.
Expected Result: A correctly set valve should allow the arm to fold slightly under heavy manual pressure. This mimics the relief action required during a collision.
Adjustment Reference:
For a standard baseline setting, adjust the valve so the threads protrude approximately 9mm past the locknut.
Tighten the locknut securely once the setting is verified.
Technical Note
The hydraulic rotary coupling is the most vulnerable component in this circuit. Proper adjustment of Valve No. 19 is the only safeguard against pressure spikes caused by external mechanical resistance.