Inside and outside surface treating technique of stainless steel drinking water pressure container

Abstract

A process applied to the treatment of the inner and outer surfaces of stainless steel drinking water pressure vessels. The outer wall is subjected to mechanical polishing pretreatment, partial mirror polishing treatment, decorative protection treatment, shot blasting treatment, surface cleaning pretreatment, pickling passivation treatment, and preheating treatment. , Surface wax penetration protection treatment, so that the surface smoothness and aesthetics are significantly improved, and the inner wall is subjected to mechanical polishing pretreatment and electrolytic polishing treatment to achieve a smooth mirror surface treatment effect on the inner surface, avoiding bacterial adhesion and breeding and improving corrosion resistance. .

Description

technical field [0001] The invention discloses a process for treating the inner and outer surfaces of stainless steel drinking water pressure vessels, which belongs to the field of manufacturing stainless steel pressure vessels in water supply systems. Background technique [0002] Stainless steel pressure vessels are often used in water supply equipment and systems, pharmaceutical machinery, and food machinery. Such pressure vessels need thicker stainless steel plates because they are under pressure. However, it is difficult for stainless steel plates over 3mm on the market to have cold Rolled plates, only hot-rolled plates can be used in the production of pressure vessels. The surface of hot-rolled plates has a layer of scale and is very rough, and must go through welding processes in the manufacturing process. The welds are prone to discoloration and oxidation. At present, pickling and passivation are mainly used. The typical treatment method is that after the container i...

AI Technical Summary

Problems solved by technology

[0002] Stainless steel pressure vessels are often used in water supply equipment and systems, pharmaceutical machinery, and food machinery. Such pressure vessels need thicker stainless steel plates because they are under pressure. However, it is difficult for stainless steel plates over 3mm on the market to have cold Rolled plates, only hot-rolled plates can be used in the production of pressure vessels. The surface of hot-rolled plates has a layer of scale and is very rough, and must go through a welding process during the manufacturing process. The welds are prone to discoloration and oxidation. At present, pickling and passivation are mainly used. The typical treatment method is that after the container is made, the surface of the original base metal and the weld seam are directly pickled and passivated, then rinsed with clean water, and the finished product is packaged after drying. This process is simple and convenient. , does not damage the base material, and the strength is not affected. However, for containers with high hygiene requirements such as food and drinking water, as well as containers that require aesthetic appearance and high corrosion resistance on the inner and outer surfaces, it is necessary to achieve beautiful appearance and inner wall. The requirements of smoothness and corrosion resistance, the above treatment process can no longer meet the requirements; it is true that there are various surface treatment methods in the society, such as shot blasting, shot blasting, polishing, etc., and they have been widely used in some industries. Common, but limited by the raw materials and manufacturing methods used in pressure vessels, there has been no mature surface treatment process matching pressure vessels. The current shot blasting or shot blasting treatment method is only for containers made of cold-rolled plates. Due to the rough surface of the pressure vessel made of hot-rolled plate, if there is no corresponding pre-treatment measures, it is difficult to achieve a beautiful treatment effect by simply using shot blasting or shot blasting. Polishing can improve some surface quality and corrosion resistance. Generally, polishing There are mechanical polishing, chemical polishing, electrolytic polishing, etc. At present, mechanical polishing is mainly manual polishing, which is time-consuming and laborious, and the effect of chemical polishing is not good. Electrolytic polishing is only suitable for small parts and parts with simple structures. As a pressure vessel, it is usually large in size. Practical electrolytic polishing method