Stainless steel gate valves have a long history and have been popularized all over the world so far, such as below DN300mm, they still dominate the various types of valves. Its main feature is that the pressure difference between the front and back of the valve plate forces the valve plate to press against the valve seat on the right side of the outlet. Welcomed by the majority of users.

       The stainless steel gate valve has a small flow resistance from fully open to intermediate opening. When it is close to full close, the flow resistance increases sharply. In a larger category, the change in flow resistance is small. When it is close to the full close, the flow rate changes greatly. It must not be used when the valve is closed. It is difficult to fine-tune the flow.

       Stainless steel gate valve has a large operating torque, which is easy to damage the valve body and stem during operation, especially for large-caliber gate valves. The size and size are also large. The DN1000 caliber gate valve is about 3200mm high and requires four people to operate. Therefore, the gate valve is individually applied to a small caliber, that is, below DN500.

       If the working condition of the stainless steel gate valve is at the side opening, the valve plate is supported by the guide rails on both sides, and the cooperation is tight when fully closed, and in the middle position, the gap between the valve plate and the guide rail is large and vibration occurs.

       To replace the stainless steel gate valve flange gasket, the following basic principles should be followed. Materials and tools must be prepared to meet relevant technical requirements and points:

      Preparation work

       ①Material: butter, cotton yarn, leak detection liquid, sealing gasket;

       ②Tools: wrench, screwdriver.

       2. Operating steps

       ① Remove the flange connection bolts, remove the valve or remove the leaking pipe section. Remove used gaskets on the sealing surface;

       ② Select the appropriate gasket and apply a layer of butter evenly on both sides;

       ③ Place the gasket on the sealing surface between the two flanges, align the center of the two flanges and the center of the bolt hole, install the bolt, screw on the nut, and tighten the nut evenly and diagonally for multiple times. It is advisable that the bolt protrudes from the nut by 2-3 pitches. After the flange gasket is installed, it should pass the working pressure test without leakage.

       3. Technical requirements

       ① Care should be taken to prevent damage to the flange;

       ② After completion, tools should be cleaned and maintained.

       4. Points for installing the gasket

       ①Choose the right: The form, material, and size of flange, bolt, and gasket should be selected appropriately according to the operating conditions and the structural form of the flange surface;

       ② Inspection: Before installation, the quality of flanges, bolts, nuts, and gaskets should be carefully checked, and there should be no burrs, unevenness, cracks and other defects. Carefully check the installation of flanges and pipes, and there should be no deviations, misalignments, holes, etc .;

       ③ Washing: The sealing surface of the flange must be cleaned, and the bolts and gaskets must be free from impurities and oil;

       ④ Installation: the gasket should be concentric with the pipe or fitting;

       ⑤ Up evenness: The mounting bolts and nuts should be evenly applied and tightened symmetrically in multiple times.