When you use the ball valve, stop valve and gate valve of steel pipe elbow, it should only be fully opened or fully closed while using and should not be used to regulated the flow, therefore it can avoid the sealing surface from erosion to accelerated wear and tear. There is reverse sealing device inside the gate valve and top thread stop valve, tightening the handwheel at the top position to prevent the media leaking from the packing. The influencing factors of polishing performance of steel pipe elbow are as below:
1. Defects on the surface of raw materials, such as scratches, pitting, over-pickling, etc.
2. The small black spots will also appear on the surface of large deformation area of the products which has been deeply drawn, thus affecting BQ property.
3. The raw material issues of steel pipe elbow: If the hardness is too low, it is hard to burnish and it appears the orange peel phenomenon easily on the surface while deeply drawing, thereby it will affect the BQ property. The BQ property with higher hardness is better than the lower hardness ones.
Steel pipe elbow fittings are usually used for welding, in order to improve the welding quality, the the ends of steel pipe elbow are beveled, left at a certain angle with a certain edge, this requirement is also more strict. There are specific regulations about the thickness of edge, the angle and deviation range, the geometric dimensions of steel pipe elbow are more than pipe fittings. The surface quality and mechanical property of stainless elbow are basically as same as the pipe, the material of stainless elbow needs to be as same as the pipe to be connected in order to welding easily.