Details of welding in the manufacture of fully welded ball valves

Release time:

2020-03-18

Details of welding in the production of fully welded ball valves.

Details of welding in the production of fully welded ball valves. Welding is the final process after the assembly of this product. The valve cavity contains non-metallic sealing materials such as rubber and polytetrafluoroethylene plastic, which cannot undergo post-weld heat treatment.
In the design of fully welded joints for valve bodies, an annular assembly gap exists at the root of the weld for alignment and positioning. This gap, under internal pressure and external loads, will produce stress concentrations several times higher than normal working stress, which is also difficult for engineers to handle.
The stress concentration, residual stress, and poor organization at the root gap of the fully welded joint of the valve body become a weak link in the valve body structure, attracting attention from the domestic and international valve industry, but there are no relevant reports on solving this problem, becoming a hidden danger to the structural boundary integrity of this product.
To prevent static electricity, steel balls and springs are installed between the stem and the ball, and between the stem and the packing box, respectively. This maintains the conductivity of all valve parts and the valve body, allowing current to pass through the area and release static electricity. This not only prevents fires but also prevents corrosion, allowing for temporary shutdowns for timely maintenance.