New Underwater Welding Process Approved By LR

Lloyd's Register of Shipping has reportedly given approval to a new process of underwater welding developed by U.K.-based UMC International Pic for permanent repairs to the shell plating of a ship. The technique allows defective areas of shell plating to be cut out and replacement insert plates to be welded into place beneath the waterline while ships are afloat, which is accomplished by the creation of an air-filled void space underwater in was of the defect.

UMC's process overcomes the necessity of welding from both the inside and outside by employing a combination of Tungsten Inert Gas (TIG) and conventional welding, using low hydrogen electrodes to overcome the difficulty. The repair is then examined using ultrasonic and magnetic particle examinations.

UMC's Managing Director David Jones explained: "Getting a welder who is a diver or putting a ship into drydock for repair are both expensive. This new method uses the specialist skills of diver and welder and effects a permanent repair from inside the ship ... It also overcomes the traditional reluctance of classification societies to accept any form of underwater welding for permanent repairs to shell plating. We expect other classification societies to follow Lloyd's in approving this new technique shortly." For more information on UMS International Pic Circle 115 on Reader Service Card