Does anyone know how the Liebherr boom winch brakes on the LR 1300 or LR1280 work? I've been on them and noticed they don't have pawls like US cranes. I thought the pawl was required on the boom winch, does Liebherr have a second brake or some type of internal pawl on these winches? Anyone got a operators manual or service manual they could page through?
multi plate disc brakes,a set of friction discs and stainless steel plates intertwined,hydraulic pressure operated.It's something along those lines (i think),sorry can't tell you precisely.
The braking system works on the principle of brake released by hydraulic oil pressure & spring applied once the joystick is returned to the neutral position. In effect an automatic brake. The hydraulic motor also acts as a brake when the joystick is in neutral as it is hydraulically locked via the spool valve. As you are in the USA Liebherr are based in Houston & this is the service centre for crawler cranes (LR). The LR1280 & LR1300 cranes are manufactured in Austria at Nenzing all larger LR cranes are manufactured in Ehingen Germany. If you are unable to source information from the US representative office check directly with the factory.
LB: agree that Liebherr should be able to help you out. They have always been great with any questions we have. Number is (757) 928-2506. Here is a recent LTM 1160 project we did: http://www.bodetechnicalservices.com/liebherr-crane-repair-service-ltm-1160.html