Wafer Check Valves, with advantages such as compact structure, light weight, and easy installation, are widely used in pipeline systems like water supply and drainage, chemical engineering, and heating, ventilation, and air conditioning (HVAC). Their core function is to prevent medium backflow and protect equipment safety. However, problems such as valve failure, pipeline vibration, and leakage caused by improper operation during actual installation occur frequently. Combined with industry practices, the common mistakes and correct operation specifications are sorted out as follows.
I. Common Installation Mistakes and Their Hazards
Reverse Installation of Flow Direction: This is the most fatal mistake. Some construction workers judge the flow direction only by the appearance and ignore the "arrow mark" on the valve body, resulting in the medium flow direction being opposite to the valve opening direction. The consequence is that the valve cannot open normally, and the sudden increase of pipeline pressure caused by medium backflow will lead to damage to the valve disc and even pipeline rupture in severe cases.
Ignoring Installation Space Requirements: Wafer Check Valves rely on the clamping and fixing of flanges at both ends. If the flange spacing is too large or too small during installation, the stress on the valve sealing surface will be uneven. Excessive spacing will cause poor sealing and medium leakage; insufficient spacing will squeeze the valve disc, affecting its flexible opening and closing, and reducing the check effect.
Improper Selection of Sealing Gaskets: Random selection of ordinary gaskets without choosing suitable materials according to the medium temperature, pressure, and corrosion is prone to gasket aging, leakage, and even medium contamination.
Uneven Force on Fastening Bolts: A faulty bolt tightening sequence and uneven installation force can cause deformation of the valve body and inadequate fitting of the sealing surface. This, in turn, may restrict the movement space of the valve disc, potentially leading to jamming of the valve.
Failing to Clean Pipeline Impurities: Installing the valve without thoroughly cleaning residual welding slag, rust, and debris from the pipeline can cause the medium to flow improperly and wear down the valve disc sealing surface. Additionally, impurities may become trapped between the valve disc and the valve seat, leading to poor sealing and potential leaks.
II. Correct Installation and Operation Methods
Preliminary Preparation: Before installation, check the valve model and specification to ensure they match the pipeline medium, pressure, and temperature; inspect the valve appearance for damage and ensure the valve disc opens and closes flexibly; clean the inner wall of the pipeline to remove impurities and welding slag, and ensure the pipeline is unobstructed.
Confirm Flow Direction and Installation Position: Strictly follow the arrow mark on the valve body to make the arrow point to the medium flow direction; preferentially install the valve in horizontal pipelines with the valve disc vertically downward to ensure smooth opening and closing; if vertical installation is required, ensure the medium flows from bottom to top.
Accurate Flange Alignment: Adjust the pipeline flange spacing to match the valve length, and ensure the flange sealing surface is flat and clean; select a suitable sealing gasket and place it in the center of the flange to avoid deviation.
Standardized Bolt Fastening: Tighten the bolts step by step in a diagonal cross sequence with uniform force to ensure the flange and the valve sealing surface fit closely without looseness; avoid excessive tightening leading to valve body deformation.
Post-Installation Inspection: Open the stop valves at the front and rear of the Wafer Check Valve, slowly inject the medium, and check for no leakage; observe the pipeline operation status to ensure no vibration or abnormal noise, and confirm that the valve disc opens and closes normally and the check function is effective.
In conclusion, the installation quality of Wafer Check Valves directly affects the stability and safety of the pipeline system. To fully utilize the valve's check function, it is essential to avoid the aforementioned mistakes and adhere strictly to the standard operating procedures. This approach will extend the equipment's service life and reduce both operation and maintenance costs.
