How to clean and install stainless steel elbow?

　　The main difference between stainless steel elbow and carbon steel elbow is the material difference. The chemical composition of stainless steel will keep the surface of stainless steel elbow from corrosion and rust for a long time, but we also need to pay attention to cleaning and installation.

　　Cleaning instructions for stainless steel elbow

　　1. According to the requirements and surface conditions of the workpiece, alkali cleaning, water-soluble cleaning agent, chlorine solvent sand blasting, shot blasting and other methods are used for cleaning;

　　2. The stainless steel elbow shall be cleaned without pickling.

　　Proper cleaning of stainless steel elbow can improve its safety performance and prolong its service life. The welding rod shall be kept dry when used. The titanium calcium type shall be dried at 150 ℃ for 1 hour, and the low hydrogen type shall be dried at 200-250 ℃ for 1 hour (repeated drying is not allowed, otherwise the coating is easy to crack and peel off), so as to prevent the coating from sticking oil and other dirt, so as not to increase the carbon content of the weld and affect the quality of the weldment. When the elbow is welded, carbide is precipitated by repeated heating, which reduces the corrosion resistance and mechanical properties. It is easy to produce cracks because of its high hardenability after welding. If the same type of electrode is used for welding, preheating above 300 ℃ and slow cooling at 700 ℃ after welding must be carried out. If post weld heat treatment is not available for weldments, chromium nickel stainless steel electrodes shall be used.

　　Installation instructions for 304 ANSI Welded Stainless Steel Elbow

　　1. Before installation, it is necessary to carefully check each standard and diameter of stainless steel elbow to see whether they meet the use requirements, eliminate the defects caused by the transportation process, eliminate the dirt of stainless steel elbow, and make preparations before installation, and make all preparations.

　　2. During installation, the stainless steel elbow can be directly installed on the pipeline according to the connection mode, and installed according to the use position. In general, it can be installed at any position of the pipeline, but it needs to be convenient for operation and maintenance. Note that the flow direction of the medium of the cut-off stainless steel elbow should be from the bottom of the longitudinal valve flap to the top, and the stainless steel elbow can only be installed horizontally. When installing the stainless steel elbow, pay attention to the tightness to prevent leakage and affect the normal operation of the pipeline.

　　3. The bolts of the packing gland of stainless steel elbow valve shall be tightened evenly, and shall not be pressed into a skew state, so as to avoid being damaged and hindering the stem movement or causing leakage.

　　4. When the ball valve, stop valve and gate valve of stainless steel elbow are used, they are only used for full opening or full closing, and are not allowed to be used for regulating flow, so as to avoid erosion of sealing surface and accelerated wear. The gate valve and upper thread stop valve are provided with back sealing device, and the hand wheel is screwed to the top position to prevent the medium from leaking from the packing.