Welding and valves officially became joined at the hip with the perfection of the arc-welding process in the late 1920s. Up until then, every component in valve was made of solid, homogeneous material, and all the end connections were either threaded or f
Valve experienced in the financial crisis era of the world economy is gradually restored, the same mechanical and electrical products in Chinese import and export market is also gradually steady growth, the valve industry will become more intense to the i
;)
;)
