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Diving bell clamp mating screws

A member has reported the following issue discovered during a ‘routine’ inspection prior to the commencement of saturation diving activities using a bottom-mating system.

The bell mating screws and clamp nuts were found to be badly worn – one set to such an extent that the nut could actually be slid along the screw without rotating the screw.

Both the screws and nuts were inspected and appeared, visually, to be in a reasonable condition, with both sets of threads looking acceptable.

With the weight of the clamp laying on the nuts and threads, the clamp appeared to operate as it should, giving a false sense of security.

The company involved has noted the need to strip down the clamping system, take the weight off the nuts and screws and undertake thorough checks of these components on a regular basis.

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