Grab Ship Unloader Manual

Can you show a picture or drawing of the pulley design?

Basic training of the drivers springs to mind.

With a grab crane as the load is transferred from the boat the load level drops. No mater what you do you will never set limits for the load level, it's all down to the driver to be vigilant and competent. The only limits that are practical are top limit and the lower/open differential. If the grab reaches the load lever at speed it will throw the ropes.

My best suggestion would be employ two burly fitters to re-reeve the ropes and then persuade the driver to be careful (or else)!

i will put some photos. we fix a roller shaft above to the pulley. then the rope will not be ejected from the pulley. please tell me "what is burly fitter"? i haven't heard it.

Installing extra pulleys may just see cables jammed, kinked or sheared.

What Tony is saying is train your operators, as only abuse, or lack of skill sees cables 'ejected'.

A grab bucket has self digging geometry.

Dropping them (to get a bigger dig) is pointless, dangerous and damages things (including bucket teeth and hinge geometry).

Is it perhaps this one?

The technique is to lower the open grab onto the material, relax lift slightly, close the bucket, and raise the load.

A "burly fitter" is a like large muscled mechanic, but generally less happy, especially about having to fix 'stupidity'.