Trepanning & 'J' Prepping
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| Machining 'J' preps in the combustion chamber tube plate. |
Tube ends projecting into the combustion chamber are prone to failure, the risk of failure is greatly reduced if the projection is removed and the tube plate is machined with 'J' type weld preparation around each tube end as detailed in BS 2790.
Combustion Chamber Tube Plate Thinning
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Combustion chamber tube plate after being thinned and the 'J' preps
machined. This tube plate was subjected to a magnetic particle inspection (MPI)
as part of the quality assurance procedure used by BTH and by many leading
Insurance and Inspecting authorities.
A method used to reduce the thickness of the combustion chamber tube plate, to
allow more rapid transmission of heat through the combustion chamber tube
plate, alleviating the problem of tubeplate and tube ends cracking.
Mirror finish and radius of tube ends ensures less heat on tube ends.