In the process of processing stainless steel flanges, due to improper operation or minor faults in the assembly line machinery, the produced flanges are defective, and the common ones are serious weld defects. In the face of such a product, no customer will want it, so the manufacturer will carry out "secondary processing" to deal with this batch of defective flanges.
At present, most companies will take three measures to deal with the defects of "defective" flanges. According to these three methods or methods, what are the disadvantages and advantages?
Method one, use machine polishing. This is a more commonly used method, but the resulting grinding marks are more obvious, resulting in uneven surface (more advanced equipment will not appear this situation), will affect the appearance, is not conducive to the recognition and acceptance of customers.
Method two, use manual polishing. Pickling and passivation treatment is carried out after manual polishing and polishing. It is difficult to achieve a uniform treatment effect for a workpiece with a large area, and an ideal uniform surface cannot be obtained. There are also its shortcomings in terms of labor costs and higher cost of auxiliary materials.
The third method is to use sulfuric acid to "clean". Generally, firstly use sulfuric acid to clean, and then manually polish the stainless steel flange, and the overall pickling and passivation will cause chemical corrosion or electrochemical corrosion to rust in the presence of corrosive media. Carbon steel, spatter and other impurities adhering to the surface of stainless steel due to scratches and welding spatter cannot be removed.
The welding seam defects of stainless steel flanges are more serious. If manual mechanical polishing is used to make up for it, the resulting polishing marks will cause uneven surfaces and affect the appearance; the overall pickling passivation will cause problems in the presence of corrosive media. Chemical corrosion or electrochemical corrosion will cause rust, and carbon steel, spatter and other impurities that adhere to the stainless steel surface due to scratches and welding spatter cannot be removed.
When bending, you must first determine the tool and slot used for bending according to the size on the drawing and the thickness of stainless 304 seamless steel pipe. Avoiding the collision of the product and the tool and causing deformation is the key to the selection of the upper mold (in the same product In the middle, different types of upper molds may be used), and the selection of the lower mold is determined according to the thickness of the plate.
Pickling and passivation treatment is carried out after manual polishing and polishing. It is difficult to achieve a uniform treatment effect for a workpiece with a large area, and an ideal uniform surface cannot be obtained. There are also its shortcomings in terms of labor costs and higher cost of auxiliary materials.
