Double-wall armoured casing - uses part cylindrical member to effect corner joints and form closed box girder

摘要

The double-walled armoured casing or housing comprises a number of plane or curved plates inter-connected by a joint portion. The joint portion is formed by a tube or part-cylindrical member and is so welded together with the plates that a closed box girder is formed extending along the edges. The joint tube or member is welded by way of two or its generatrices to two inner wall plates the edges of which are joined, near the edges and extends round the joined edges on the outside. The outer wall plates are connected tangentially to the corner tube or member.