Skip to Main Content

Abstract

In TAKR 300 (Bob Hope) Class transport ships, the builder observed cracking of steel cloverleaf vehicle tie-down deck sockets following installation. Sockets were made from AH36 steel plate by flame cutting and cold coining, then submerged-arc welded to the shop deck. Cracks initiated from the tip of the cloverleaf pattern in >300 cases aboard several cargo vessels in various stages of construction. Consultants who analyzed the situation concluded that the problem may have been corrosion and hydrogen embrittlement. Three possible mechanisms of failure were considered: overload failure; fatigue fracture; and, environmentally-assisted cracking. Testing indicated overload failure was the cause. Remedial actions were taken to improve the fracture properties of the deck socket. A modified manufacturing process was developed involving milling and cutting instead of coining to round the comers of the flame-cut cloverleaf lobe. This new manufacturing process solved the problem.

You do not currently have access to this chapter.
Don't already have an account? Register

2019. "Structural Components", ASM Failure Analysis Case Histories: Offshore, Shipbuilding, and Marine Equipment

Download citation file:


Close
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal