1. The processed components and finished products shall not be disposed of externally until they are accepted by experience.

2. The burrs on the outer surface of the welded steel pipe, welding skin, welding knobs, spatters, dust and scale, etc. should be cleaned before removing rust, and loose oxide scale and thick rust layer should be removed at the same time.

3. If there is oil and grease on the surface of welded steel pipe, it should be cleaned before rust removal. If there are oil stains and grease on only a part of the area, partial disposal methods are usually optional; if there are large areas or all areas, you can choose a solvent or hot alkali for cleaning.

4. When there are acids, alkalis, and salts on the surface of the welded steel pipe, you can choose to wash them off with hot water or steam. However, attention should be paid to the disposal of waste water, which cannot cause environmental pollution.

5. Some newly rolled stainless steel pipes are coated with curing paint in order to avoid rust during short-term storage and transportation. The stainless steel pipes coated with curing paint shall be disposed of according to specific conditions. If the curing paint is a two-component coating cured by a curing agent, and the coating is basically intact, it can be treated with emery cloth, stainless steel tube velvet or light eruption, and the dust can be removed, and then the next step of construction .

6. The coating for curing the primer or usual primer of the outer surface of welded steel pipe is usually determined according to the status of the coating and the next supporting paint. Anything that cannot be used for further coating or affects the adhesion of the next coating should be removed in full.