The silent check valve is also known as the nozzle-type check valve and the axial-flow check valve.

It consists of the valve body, valve seat, valve plate, valve shaft, spring, and guide fluid.

Both the silent check valve and the sound-absorbing check valve have the effect of reducing noise, but the sound-absorbing check valve has a better noise reduction effect and is cheaper. The sound-absorbing check valve can be applied in some extreme working conditions. It has a higher cost. Both can be installed vertically and horizontally.

The sound-absorbing check valve has a lifting structure, while the silent check valve has a Venturi structure.

The sound-absorbing check valve can reduce the noise to below 80 decibels, while the silent check valve can reduce the noise to below 60 decibels.

The back of the valve seat of the sound-absorbing check valve is designed with a T-shaped groove and a T-shaped sealing ring. They are closely fitted to prevent the medium from flowing back and to make the sealing strip on the valve plate and the valve seat contact to achieve sealing, with zero leakage. While the silent check valve uses an overall rubber coating process, using the rubber of the valve plate and the valve seat for sealing to achieve zero leakage.

The sound-absorbing check valve is irreplaceable in fire protection systems and is more widely used.