Check valve test status: lift check valve disc axis is in the position perpendicular to the horizontal; swing check valve channel axis and disc axis are in the position approximately parallel to the horizontal.

During the strength test, the test medium is introduced from the inlet end to the specified value, and the other end is closed to see that the valve body and bonnet have no leakage.

In the sealing test, the test medium is introduced from the outlet end, and the sealing surface is checked at the inlet end. It is qualified if there is no leakage at the packing and gasket.