Tube sheet welding
AssigneesPublic Service Electric and Gas Company, ICI Americas Inc.
InventorsRenato R. Noe, Edward A. Fox
Life of this patent
Estimating the term…
Abstract
An improved method for the explosive expansion and welding of tubes to tube sheet includes trepanning the rear face of the tube sheet to form integral collars around each tube-receiving bore in the tube sheet. The collars prevent accumulation of corrosive material in a gap between the tube and tube sheet bore, and provide support to the tube wall when the tube is explosively expanded beyond the region of the tube surrounded by the collar.
Claims11
In a method for explosively welding and expanding a tube to a tube sheet, comprising the steps of
- locating said tube in a bore formed in said tube sheet for accommodating said tube, said bore extending completely through said tube sheet from a front face to a rear face thereof, such that an end of said tube is near said front face and a remaining portion of said tube projects inwardly through said tube sheet and emerges beyond said rear face,
- positioning an explosive means selected to yield, a predetermined explosive force when detonated, in said tube at a location near said front face of said tube sheet, and
- detonating said explosive means so that the resulting detonation welds at least a first region of said tube within said bore near said front face and expands a second region of said tube within said tube sheet farther remote from said front face than said first region,
- the improvement comprising the additional steps of
- trepanning an annular groove, having an inner diameter greater than the diameter of said bore, in said rear face of said tube sheet around said bore so as to form an integral annular collar around said bore, and
- selecting said explosive charge so as to yield a predetermined explosive force sufficient to expand said tube such that said second region extends from said first region to a point immediately beyond a point at which said tube emerges from said annular collar
In a combination comprising a tube and a tube sheet to which said tube is to be explosively welded and expanded, wherein
- said tube sheet has a bore formed therein extending from a front face to a rear face of said tube sheet, said tube inserted in said bore such that a first end thereof is near said front face and a remaining portion of said tube extends through said tube sheet and emerge beyond the rear face of said tube sheet, and wherein
- an explosive means selected to yield a predetermined explosive force when detonated is located within said tube near said front face and which, when detonated, explosively welds said tube within said bore in a first region near said front face and expands said tube within said bore in a second region of said tube within said tube sheet farther remote from said front face than said first region,
- the improvement wherein,
- an annular groove, having an inner diameter greater than the diameter of said bore, is cut in said rear face around said bore, thereby forming an integral annular collar around said bore, and
- said predetermined explosive force expands said tube such that said second region extends from said first region to a point immediately beyond a point at which said tube emerges from said annular collar.
Dependencies are inferred from the claim text.