Process for production of double-metal metallurgical composite tube through high frequency resistance welding method and composite tube

Abstract

The invention provides a process for production of a double-metal metallurgical composite tube through a high frequency resistance welding method and the composite tube. The process comprises the steps that firstly, a metallurgical composite steel tube with an inner corrosion-resistant alloy lining and an outer base tube is formed; secondly, weld joint grooves in the lining are formed; thirdly, the metallurgical composite tube is formed; fourthly, weld joints for repair welding are formed, so that continuity of the corrosion-resistant alloy lining is achieved. The production process has the advantages of both hot rolling metallurgical composition and electric resistance welding; a hot-rolled metallurgical composite base layer and the lining are combined in a metallurgical mode through a hot rolling method, so that high combination strength is achieved, and the situation that the corrosion resistance of the lining is affected by alloying element dilution due to dissimilar metal welding is avoided. Due to the fact that the base tube and a lining tube are combined in a metallurgical mode, the composite tube can be subjected to circumferential weld welding on a construction side with no need for circumferential build-up welding or sealing welding of tube ends. The production process is simple, convenient, easy to implement, and reliable in quality; transition welding materials are not needed between the base tube and the lining, so the welding materials and welding time can be saved, and production efficiency is high.

Description

technical field [0001] The invention relates to the technical field of steel pipe manufacturing, in particular to a process for producing a bimetallic metallurgical composite pipe by using a high-frequency resistance welding method and the composite pipe. Background technique [0002] When using traditional carbon steel or low alloy steel pipes to transport corrosive media, the corrosive media will cause serious corrosion of carbon steel or low alloy pipes. Choosing appropriate corrosion resistant alloy materials such as stainless steel can resist the corrosion of the medium and prolong the life of the pipeline. commonly used ways. However, if pure corrosion-resistant alloy pipes are used, the material cost is expensive, and the strength and toughness of corrosion-resistant alloy materials are often low, and thicker wall thickness is required to meet the design strength requirements, which brings unbearable costs to pipeline construction pressure. In this case, it is a rea...

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Problems solved by technology

[0003] The currently used bimetallic composite pipes include metallurgical composite pipes and mechanical composite pipes. Among them, metallurgical composite pipes mainly use surfacing welding or centrifugal casting to form a corrosion-resistant alloy layer on the inner surface of the base pipe, which is costly and expensive. The quality control of the lining alloy is difficult, and the inner surface of the composite pipe often needs to be machined to achieve the specified surface quality and geometric dimensions, and the production efficiency is low

The mechanical composite pipe usually adopts hydraulic method, explosion method or spinning method to form an interference fit between the corrosion-resistant alloy liner and the base pipe, so as to achieve the effect of mechanical composite. This method has the advantages of low cost and easy raw materials. However, due to the mechanical combination between the base pipe and the liner, the bonding strength is low, which may easily cause the slippage between the base pipe and the liner and the bulge (collapse) of the liner during subsequent coating and use, affecting its Reliability of use. In addition, mechanical composite pipes often need to be welded and sealed at the end of the pipe to facilitate butt welding and inspection of steel pipes in subsequent construction.

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