Padeye
Padeye
(OP)
I am designing a lifting padeye for a jacket. The main plate thickness comes up to about 100mm and the cheek plate is about 50mm. I specified through thickness property for both the main plate and cheek plate. My client wants to know why through thickness property is required for the plates.
The only reason I could think of is that there may be impact loads on the padeye therefore we need the padeyes to be of through thickness property to satisfy the Charpy impact test.
Is there any other reason why through thickness plates are required? It seems pretty common to use through thickness property plates for padeyes.
The only reason I could think of is that there may be impact loads on the padeye therefore we need the padeyes to be of through thickness property to satisfy the Charpy impact test.
Is there any other reason why through thickness plates are required? It seems pretty common to use through thickness property plates for padeyes.





RE: Padeye
It is common practice to specify materials for lifting points and the plates or members to which the lifting point is attached that have guaranteed through-thickness properties.
However, the Shell Guidelines for Lifting Points and Heavy Lift Criteria, doc EM/039 allows otherwise if the design is such that through-thickness stresses are avoided.
Your plates are thick, and inclusions may be possible as part of the rolling process. So if you can configure the lifting point to have no plates loaded at right angles to the direction of rolling and in shear rather that tension you could get away without specifying through-thickness properties. It is a matter of judgement and reviewing how the stresses are distributed locally to the lifting point to see if an inclusion would cause a problem.
RE: Padeye
Shell U.K. Ltd. Guidelines for Lifting Points and Heavy Lift Criteria. Engineering
Reference Document No. EM/039 Rev. 3, 1991.
or
Brown & Root. Joint Industry Project: Heavy Lift Criteria. Brown & Root Vickers
Technology Ltd, 1991.
Thanks