The study on the dynamic characteristics of the disc for the lift-type check valve

Lift-type check valve of which the opening or closing stroke can be operated by the flow change through the disc is commonly used for the prevention of reversing flow and protection of the main components at many systems in nuclear power plants. Under the normal operating conditions, if the disc can not be fully opened due to the inadequate valve selection, many problems like corrosion, wear or stick by the foreign material can be occurred and they can give impact to the safety related system on their safety functions. Therefore, the exact understanding for the dynamic motion of the disc is very important. In this paper, the dynamic motion of the lift check valve was investigated experimentally. The pressure and flow conditions were controlled by the opening position (OP) of air-operated valve (AOV) that is installed at the downstream of the check valve. In addition, the effect of upstream elbow on the valve opening was analyzed based on the experimental data