Load Testing Of Tiedown Padeyes

[thehun1314]

Hi Folks,
I have a question regards to load testing of tie down padeyes using two jacks and a test frame. Would I be right in saying If I had a to load test a 50 tonne padeye I would only have to put 37.5 tonne on each jack or will I have to put 75 tonne on each jack, This question has been brought up a number of times and each time my engineers have different answers, Can somebody please put me strait on this?
Thanks

 

[ishvaaag]

I don't understand well your particular setup but free body diagrams showing the forces at the selected parts will identify the required forces for equilibrium; then just put the known one, and identify the others from trigonometry.

 

[dik]

Can you send a sketch of what you are planning?

Dik

 

[thehun1314]

Basically the issue we have here is we are unsure if which force we should be putting on each jack to achieve the 50 ton on the padeye. I have attached a very basic viso drawing, I hope it makes my requested a little more clearer.

 

[ishvaaag]

Then if the padeye sits amidst the pin between the jacks, you need to load each jack to half your desired proof value. The retainment force in the padeye is supported in half through each jack to the sides, just a mirror of the beam with a single load amidst its span.

 

[fancypants]

Assuming your padeye is at the center and you have the jacks piped together so that the pressures are the same in each, you should have a reaction of about 1/2 of the applied test load at each jack. If you need to test to fifty tons, then the reactions would be 25 tons at each jack.

 

[dhengr]

You may want to proof test the padeye and its connection to a multiple of the load you rate it at, thus the possible difference in the jack forces the engineers are giving you. You might want to ask them what jack forces to use, and get them to explain this problem to you. You might also want to get a couple text books on Statics and Strength of Materials, or better yet take a couple classes on these subjects. This is a pretty basic engineering question and the people who buy the equipment to which the padeyes are connected are counting on you to get it right, and so is your boss, so you should have a vague idea what you are doing.

 

[csd72]

thehun,

this is really basic statics, no high school physics. Are you actually a mechanical engineer!

Also how can a pin be ageist? does it refuse to work with the older pins?