Bimetal composite tube

Abstract

The invention discloses a bimetal composite tube which comprises an outer tube, connecting portions and an inner tube. The connecting portions are arranged at one end or two ends of the bimetal composite tube, the connecting portions and the inner tube are made of identical materials, the inner diameter of each connecting portion is consistent with that of the outer tube, and the wall thickness of each connecting portion is not smaller than the wall thickness of the outer tube; the outer tube is connected with the connecting portions by means of welding; the inner tube is tightly combined with the outer tube and the connecting portions by a certain forming method; the ends of the inner tube and the ends of the connecting portions are subjected to seal welding, so that corrosive media in pipelines are guaranteed against being in contact with the outer tube. The bimetal composite tube has the advantages that special materials among the connecting portions of the composite tube and the outer tube are welded in a manufacturing plant, so that a welding condition is good, quality inspection can be strictly executed conveniently, the welding strength can be guaranteed, only welding of the same type of metal needs to be completed during field construction, and the requirement on the connection strength between the pipelines can be met; the connecting portions are made of the corrosion-resistant materials, so that corrosion of the connecting portions can be prevented, and the delivery safety performance of the bimetal composite tube can be guaranteed.

Description

technical field [0001] The invention belongs to the field of petrochemical industry, in particular to a bimetal composite pipe. Background technique [0002] In recent years, with the development of the economy, the demand for energy has increased sharply, and international and domestic efforts to exploit oil and natural gas have been intensified. As an economical, safe and uninterrupted long-distance transportation tool for oil and gas, oil and gas pipelines have developed rapidly. In my country's Tarim, Sichuan, Changqing and other oil and gas wells contain H 2 S, CO 2 , Cl - Such corrosive media are extremely corrosive to pipelines, aggravate pipeline damage, and cause huge economic losses and environmental pollution. Traditional pipes are gradually not used in oil and gas wells containing highly corrosive media and their transportation processes, and corrosion-resistant pipes are used. Alloys are expensive, so bimetal composite pipes came into being. The bimetallic ...

AI Technical Summary

Problems solved by technology

The thickness of the anti-corrosion alloy layer in the inner layer of the existing composite pipe is small, generally 2-4mm. Due to the limitation of environmental conditions, it is difficult to completely align the ends of the two composite pipes during on-site welding, resulting in dislocation of the inner layer of anti-corrosion alloy. After the welding is completed, the joints are partially The inner alloy layer becomes thinner and even contacts the outer carbon steel, and the corrosive medium causes a sharp decline in the corrosion resistance of the joint, greatly reducing the corrosion resistance and service life of the entire pipeline

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