Opening and closing parts by the media flow and power to open or close their own to prevent media backflow valve called the check valve. Check valves are automatic valves, mainly used for medium flow of one-way pipe, only allow medium to flow in one direction to prevent accidents. Check valve installation should pay attention to the following matters: 1, do not make the check valve in the pipeline to bear the weight of large check valve should be independent support, so that the impact of pressure from the pipe system. 2, when installing, pay attention to the direction of the flow of the medium should be consistent with the arrow direction of the body ticket. 3, vertical drop-check valve should be installed in the vertical pipe. 4, lift-level flap check valve should be installed on the level of the pipeline. Check Valve Category: First, according to the material classification (check valve body material) 1. Cast iron check valve 2. Brass check valve 3. Stainless steel check valve Second, by functional classification 1. NRVZ mute Check valve 2.NRVG quiet check valve 3.NRVR silent check valve 4.SFCV rubber valve check valve 5.DDCV double valve check valve 3. According to the structure 1. Lift check valve, Divided into vertical and horizontal two. 2. Swing check valve is divided into single-valve, double-valve and multi-valve three. 3. Butterfly check valve, straight-through several types of check valves in the connection form can be divided into thread connection, flange connection and welding three.
