1. The check valve couldn't bear weight, large size check valve must installated independently, so the piping system won't affected by the pressure. 2. The lift type check valve with vertical disc should be installed in vertical pipe. 3. The lift type check valve with horizontal disc should be installed in horizontal pipe. 4. When installing, should pay particular attention to medium flow direction, the direction of mediam flow should be consistent with the arrow direction on body, or it will cut off the flow. Foot valve should installated at the bottom of the pump suction pipe. 5. The installation location of swing type check valve is unrestricted, usually installed in horizontal pipe, also could installed in vertical pipe or sloping pipe. 6. Horizontal lift type check valve should be installed in horizontal pipe, Vertical lift type check valve and foot valve must be installed in vertical valve, the media flow from the bottom to top. 7. Single-plate swing tpye check valve are generally applicable to medium size pipe. When large size pipe select single-plate swing tpye check valve, for reduce the water hammer pressure, choose slow-closure type check valve for reduce the water hammer pressure is better. 8. Dual-plate swing type check valve fitted to large size pipe. Butt-welded dual-plate swing type check valve has small structures, light weight. Multi-disc swing type check valve is fitted to large size pipe system. Source: Valvehardware
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