Recent content by Marinel

Any news?

The mesure device is a Load Pin Cell located in the shaft of pulley nº 5 which does not move at all. I cannot introduce any extra device on the rope because it will moves and can smahed against pulleys. If my formulas are right then it is a friction problem and because the friction is too high...

Drakkith, I want to load the crane with 143 Tons in order to adjust the trip relay ( to avoid manipulation of the crane with that load or bigger). But due to friction (?) if i load the crane with 143 tons I start to measure 135 tons ! If for instance I can adjust the trip for 143 tons, later...

Thanks for your contributions! Could you tell me if the developed formulas are correct?

I forgot the file

I need to adjust the safety trip at 110% of the nominal load ( 130 tons ). This means that I need to load the overhead crane with 143 Tons. With this load on the floor I start to rise the load with the crane, but I measure less than those 143 Tons ( say 135 Tons). This means that we can never...

May be we can simplify the problem using the arrangement below. What will be the force in the rope when it goes up with no acceleration? And what happens if we stop the lifting?

OK, I can understand what you say, but that is just a feeling. Can you or someone describe it mathematically? The feeling I have already but that's all!I would like to have the evidence of the phenomenon.

You are right! The force at pulley is 2XF1 and not 4X. In fact I have a display showing the real load and that's whya mmy mistake. I thought that the problem is concerned with the deformation of the rope but I cannot explain how it works. The length of each rope ( distance from 3 to 5 ) is...

The problem bellow is a real problem and I would like to get some ideas in order to overcome it. As you can see in the attached doc, we have two winches ( drum 1 and 2 ) on the same shaft of motor M1, two moving pulleys ( 3 and 4 ) and a fixed pulley (5). The load is 130 Tons, and we can...

The problem bellow is a real problem and I would like to get some ideas in order to overcome it. As you can see in the attached doc, we have two winches ( drum 1 and 2 ) on the same shaft of motor M1, two moving pulleys ( 3 and 4 ) and a fixed pulley (5). The load is 130 Tons, and we can...

I understand what you say, but when is raising shows 30 Ton and when go down shows 36,2 Tons. I have checked the system and load cell at pulley 5 is OK ( I have already changed it by another one ). The pulley doesn't move at all, only slightly when the movement starts. Also I have checked the...

As you can see in the attached doc, we have two winches on the same shaft of motor M1, two moving pulleys ( 3 and 4 ) and a fixed pulley (5). The load is 130 Tons, and we can measure that with a load cell at pulley 5 ( 32,5 Tons) when we stop the lifting of the load. But when the load is...