Method of manufacturing gradual-change bore diameter stainless steel antipriming pipe

Abstract

The invention provides a preparation method for a stainless steel perforated pipe with gradually-varied aperture, the invention adopts the preparation process that stainless steel powder is mixed with a certain polyvinyl alcohol solution to prepare stainless steel powder suspension, and getter is added into the suspension and poured into a two-piece-type opening and closing rigid pipe die made of stainless steel after even stirring, which centrifugally takes shape on a centrifuge, thereby preparing a green body of the stainless steel perforated pipe with gradually-varied aperture grads; the green body is dried in a blast-type baking oven, and then the demoulding is performed; the green body of the stainless steel perforated pipe after drying is sintered in a vacuum stove, the sintering atmosphere adopts vacuum, and the stainless steel perforated pipe with gradually-varied aperture grads is prepared after cooling. The invention has the advantages that the demoulding attainment rate of the green body of the stainless steel perforated pipe with gradually-varied aperture is greatly enhanced, and the filtering precision of the perforated pipe is ensured; meanwhile, the air transmission coefficient of the stainless steel perforated pipe with gradually-varied aperture is enhanced, and the preparation method solves the phenomenon of the reciprocal relationship between the filtering precision of the stainless steel perforated pipe and the transmission performance in the filtration, separation and application process.

Description

technical field [0001] The invention relates to a method for preparing a metal porous pipe, in particular to a method for preparing a stainless steel porous pipe with variable apertures. Background technique [0002] At present, most porous metal filter materials are based on uniform porous metal materials, and one or more layers of porous membranes are coated on the surface to improve the filtration accuracy. With the rapid development of industry, the requirements for filter materials are getting higher and higher. As the matrix of the filter membrane layer, uniform porous materials can no longer meet the requirements of large air permeability and high precision in some departments. [0003] Metallic porous materials are a class of metal materials with obvious pore characteristics (porosity can reach up to 98%). In terms of the use environment, compared with organic and ceramic porous materials, it mainly has three advantages: high mechanical strength, good thermal conduc...

AI Technical Summary

Problems solved by technology

Sudden change (also known as step shape - with obvious material interface) pore size gradient porous material is a filter control layer or transition layer attached to the support of the previous layer of large pores, because the particle diameter of the powder is mutated, the next layer The particles will block the upper layer of large pores, thereby reducing the permeability of the porous material, and the multiple molding and sintering processes used will increase the manufacturing cost of the metal porous material. These disadvantages are not conducive to its large-scale and wide application.

[0005] The invention patent with the application number of 200510033633.3 "Porous non-layer boundary gradient metal film tube and its preparation method" introduces a preparation method of a porous non-interface gradient metal film tube, but does not state the specific properties of the corresponding powder corresponding material; in addition, the The preparation method of the metal porous tube described in the patent has some disadvantages: for example, after the metal porous tube is formed, the green body of the porous tube is not easy to demould, and the thickness of the metal porous tube is not easy to control, etc.

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