How to ensure that the surface of stainless steel welded pipe is not damaged?

Stainless steel welded pipe in the production, transportation, storage, use of the process of improper operation will cause damage to the surface of the stainless steel welded pipe, in order to ensure that the surface of the stainless steel pipe is not damaged and contaminated, in the production of various processes we should strengthen the protection of stainless steel pipe.

There should be a special storage rack, the storage rack should be wooden or painted surface of the carbon steel bracket or padded with rubber mats, in order to isolate from other metal materials such as carbon steel. When stored, the storage location should be convenient for lifting, and other materials storage area is relatively isolated, there should be protective measures to prevent contamination by liquids, prevent mutual impact with other components, anti-ferrous metal pollution and damage.

Stainless steel pipe lifting, should use special lifting gear, such as lifting straps, special clevis, etc., prohibited the use of steel wire rope in order to avoid scratching the surface; and in the lifting and placing, should be avoided when the impact of the bump caused by scratches.

If there are surface scratches, arc traces and surface contamination during transportation, storage and processing, it must be completely removed, polished with an angle grinder, and then polished with polishing pads or metallurgical sandpaper.

According to the requirements of welding, the surface of the weld is not allowed to have more than visible cracks, unwelded defects, not allowed to have more than 0.5mm biting edge and slag entrapment.

The internal weld penetration rate of the weld is more than 95%, and the internal concavity is less than 0.5mm; the circumference of the fillet weld is fully welded, and the thickness of the welded fillet after welding is more than 1.1 times of the wall thickness.

Weld corner and joints, there shall be no corners, flying edges and other phenomena, should be smooth transition.

After welding the first line of PT inspection, qualified, the pressure for the working pressure of 1.25 ~ 1.5 times the hydrostatic test.