Method for manufacturing bimetallic metallurgical composite pipe by pressure welding composite method

Abstract

The invention provides a method for manufacturing a thermometal metallurgy composite tube in a pressure welding composite mode, and provides a manufacturing method for the metallurgy composite tube which is safe, reliable and high in interlayer bonding strength. According to the technical scheme, the method for manufacturing the thermometal metallurgy composite tube in the pressure welding composite mode includes the steps that an inner tube is coaxially mounted in an outer tube, inert gas is inflated to manufacture a tube blank after interlayer sealing is conducted on two ends of the tube, wherein a tapered flaring is formed in one end of the inner tube; the tube blank penetrates through an induction heating coil on an annular welding support and a welding core bar encircled by positive electrodes and mounted on a tail base, is fixedly connected with a pressure welding circular cone bearizing welding head at the position of the head portion of the welding core bar, and is clamped in a pneumatic chuck of a power head on a machine tool moving working table, the power head pulls the tube blank to rotate at a constant speed to the left, the positive electrodes are pressed down and are powered on, a V-shaped annular high-frequency current scanning heating zone or a resistance welding electrode pressing heating zone is formed on the tube blank interlayer surfaces between the positive electrodes and the negative electrode of the pressure welding circular cone bearizing welding head, metal on the bonding surface is fused, the tube blank is forced to pass through the axially fixed circular cone bearizing welding head, and the tube blank is welded into a whole.

Description

technical field [0001] The invention relates to a metallurgical compound processing field, which is widely used in petroleum, chemical industry, electric power, metallurgy and other industrial fields, seawater desalination, pharmaceutical chemical industry, sewage treatment, new energy, food processing and other industries to manufacture bimetal Metallurgical composite pipe method. Background technique [0002] In order to obtain a new kind of pipe with new energy or greatly reduce the construction cost of high-corrosion pipelines, various bimetallic composite pipes have emerged as the times require. For example, a boiler heat exchange tube coated with stainless steel and lined with low-carbon steel not only maintains the high thermal conductivity of low-carbon steel, but also has excellent high-temperature corrosion resistance. Another example is that stainless steel pipes or nickel-based alloy pipes are usually used as pipeline materials in the pipelines of strong corrosi...

AI Technical Summary

Problems solved by technology

The molding characteristics of explosive composite lead to the following disadvantages: (1) The interface bonding area is wave-shaped, and it is difficult to achieve complete metallurgical bonding at the bonding surface, the bonding force is small, the residual stress in the bonding area is large, and there is a phenomenon of aging stratification

This delamination phenomenon brings great difficulties to the subsequent welding connection of pipelines

(2) If the inner layer metal has a higher yield strength or a larger wall thickness, greater explosion energy is required during the explosive forming process. Excessive explosion energy can easily cause simultaneous plastic deformation of the inner and outer tubes, resulting in Forming failure

The main disadvantages of using the surfacing method to manufacture composite pipes are: the cost of large-area surfacing is extremely high; the combination of materials that can be produced is limited to materials with compatibility under fusion welding, and two materials with a large difference in melting point cannot be combined; Overlay welding is often used for the cladding of stainless steel pipes and carbon steel pipes, and the qualified rate of one-time welding of composite pipes is low. After overlay welding, necessary mechanical processing is required on the metal surface of the weld layer, which further increases the manufacturing cost.

Hot-rolled cladding is often used to process pipes with small wall thickness. The disadvantage is that the one-time investment is large, and many material combinations cannot be realized by rolling and cladding.

[0017] Hot rolling and hot extrusion process, explosive compounding, and liquid phase diffusion welding are also metallurgical bonding, with poor structure, low bonding force and high production cost

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