Weld joints involving dissimilar metals and methods for forming same
AssigneeNational Oilwell Varco, L.P.
InventorsWilliam Randal Bunker, Helna George, Rajagopala N. Pillai
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Abstract
A method of joining a steel first member to a stainless steel second member includes buttering a first joint surface on the first member, the buttering including: preheating the first joint surface; welding a border layer of weld material to the first joint surface; and heat treating the border layer and the first joint surface after welding the border layer. A weld is formed between the first and second members after heat treating the border layer and the first joint surface. The border layer and a second joint surface on the second member are preheated; and a body of weld material is added between the border layer and the second joint surface.
Claims11
A method of welding to join a high-strength low alloy steel first member to a stainless steel second member, the method comprising:
- buttering a first joint surface on the b-strength low alloy steel first member, wherein buttering comprises:
- preheating the first joint surface;
- welding a border layer of weld material to the first joint surface;
- and
- heat treating the border layer and the first joint surface after welding the border layer;
- and
- forming a weld between the alloy steel first member and the stainless steel second member after heat treating the border layer and the first joint surface, the forming comprising:
- preheating the border layer and preheating a second joint surface on the stainless steel second member;
- and
- adding a body of weld material between the border layer and the second joint surface.
Dependencies are inferred from the claim text.