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5) Winch
The winch consists of hydraulic motor, gearbox and winch drum.
The winch is installed inside of the column structure. The
hydraulic brake is included in winch gearbox.
5 - 3 OLP (over load protection) system
The OLP system is a fully hydraulic concept that stops the main
hydraulic flow when the pressure in the derrick cylinder has
reached the maximum allowable level, preventing aggravating
movements.
The safety system resets automatically after a pressure
decreasing movement.
Although the safety system is triggered by the pressure of the
derrick cylinder only, it prevents all aggravating movements.
Only the extension can be moved inwards as an exception, to
solve the overload situation. The crane and vehicle have a
guaranteed stability.
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