Hot pressure welding of hot steel stock
AssigneeSumitomo Metal Industries, Ltd.
InventorsSeiji Okada, Yutaka Suzuki, Kouichi Sakamoto, Hitoshi Teshigahara, Takao Taka, Yasuto Fukada, Masami Oki
Life of this patent
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Abstract
A method of hot pressure welding of hot steel stock, in which the ends of the steel stock are descaled mechanically and pressure joined under a reducing flame. Since re-oxidation after descaling is prevented and the feasible temperature for hot pressure joining is maintained by the reducing flame, the joining is accomplished firmly and strong joints are obtained.
Claims26
A method of carrying out hot pressure welding of hot steel stock, comprising mechanically descaling the joining portions of the hot steel stock followed by pressure joining the portions, the descaling and pressure joining steps being carried out in a reducing atmosphere, the reducing atmosphere being obtained by combusting fuel and combustion air under conditions defined by the following formula:
- P.gtoreq.286 m-172 (1)
- wherein, P is an oxygen enrichment ratio of oxygen in the combustion air (% by volume) and m is an oxygen ratio of oxygen combusted relative to an amount of oxygen required for complete combustion of the fuel.
A method of carrying out hot pressure welding of hot steel stock, characterized by mechanically descaling the .joining portions of the hot steel stock prior to pressure joining in a reducing atmosphere, which is obtained by combusting fuel and combustion air under conditions defined by the following formula:
- P.gtoreq.286 m-172 (1)
- wherein, P is an oxygen enrichment ratio of oxygen in the combustion air (% by volume) and m is an oxygen ratio of oxygen combusted relative to an amount of oxygen required for complete combustion of the fuel, the mechanical descaling being carried out with a rotary cutting tool.
A method of carrying out hot pressure welding of hot steel stock, comprising mechanically descaling the joining portions of the hot steel stock followed by pressure joining the portions, the descaling and pressure joining steps being carried out in a reducing atmosphere, the reducing atmosphere being obtained by combusting fuel and combustion air under the conditions defined by the formulas (1) and (2), or the formulas (1) and (3),
- P.gtoreq.286 m-172 (1)
- P.gtoreq.-113 m+90 (2)
- P.ltoreq.-94 m+143 (3)
- wherein, P is an oxygen enrichment ratio of oxygen in the combustion air (% by volume), and m is an oxygen ratio of oxygen combusted relative to an amount of oxygen required for complete combustion of the fuel.
A method of carrying out hot pressure welding of hot steel stock, characterized by mechanically descaling the joining portions of the hot steel stock prior to pressure joining in a reducing atmosphere, which is obtained by combusting fuel and combustion air under the conditions defined by the formulas (1) and (2), or the formulas (1) and (3),
- P.gtoreq.286 m-172 (1)
- P.gtoreq.-113 m+90 (2)
- P.ltoreq.-94 m+143 (3)
- wherein, P is an oxygen enrichment ratio of oxygen in the combustion air (% by volume), and m is an oxygen ratio of oxygen combusted relative to an amount of oxygen required for complete combustion of the fuel, the mechanical descaling being carried out with a rotary cutting tool.
A method of carrying out hot pressure welding of hot steel stock, comprising mechanically descaling the joining portions of the hot steel stock followed by pressure joining the portions, the descaling and pressure joining steps being carried out in a reducing atmosphere, the reducing atmosphere being obtained by combusting fuel and combustion air under the conditions defined by the formulas (1), (2) and (3),
- P.gtoreq.286 m-172 (1)
- P.gtoreq.-113 m+90 (2)
- P.ltoreq.-94 m+143 (3)
- wherein, P is an oxygen enrichment ratio of oxygen in the combustion air (% by volume), and m is an oxygen ratio of oxygen combusted relative to an mount of oxygen required for complete combustion of the fuel.
A method of carrying out hot pressure welding of hot steel stock, characterized by mechanically descaling the joining portions of the hot steel stock prior to pressure joining in a reducing atmosphere, which is obtained by combusting fuel and combustion air under the conditions defined by the formulas (1), (2) and (3),
- P.gtoreq.286 m-172 (1)
- P.gtoreq.-113 m+90 (2)
- P.ltoreq.-94 m+143 (3)
- wherein, P is an oxygen enrichment ratio of oxygen in the combustion air (% by volume), and m is an oxygen ratio of oxygen combusted relative to an mount of oxygen required for complete combustion of the fuel, the mechanical descaling being carried out with a rotary cutting tool.
Dependencies are inferred from the claim text.