Elastic Seat Butterfly Valve

This Dafugui elastic seat butterfly valve is of high quality and durable. It uses a metal-to-metal or composite plate sealing structure and achieves zero leakage through a flexible stainless steel sealing ring. It can maintain a tight seal and remain undeformed even under high or low temperature conditions.

Product Parameters

Analysis and Problems

The elastic seat butterfly valve consists of main components such as the valve body, valve plate, valve stem, elastic seat, and pressure ring.

The pressure ring's structure and function: The side of the pressure ring forms a sealing pair with the valve body and the pipe flange. Bolt holes are present on the side; bolts are used to tighten the pressure ring, securing the valve seat and integrating it with the valve body to form the overall structural length of the valve.

Because of the bolt holes on the side of the pressure ring, the effective sealing surface diameter is reduced. Most users use slip-on flanges, whose nominal inner diameter is 10-20mm larger. This reduces the effective sealing surface. If the valve and pipe flange are not concentric during installation, the valve will misalign and press against the bolt holes. In this case, the bolt holes will be exposed inside the pipe flange's inner bore, causing leakage. The leakage is characterized by the medium flowing out from the back of the pressure ring.

Acceptance Precautions

Due to structural reasons, leaks occurred during testing and acceptance, leading the user to notify the manufacturer of non-compliance. However, after communication, the products passed inspection smoothly and operated without issues. Therefore, the following precautions are provided to help users better understand and use elastic seats.

1. When testing an elastic seat butterfly valve, lay it flat with the pressure ring side facing upwards. Place a pressure plate on this flat surface that is approximately the same size as the flange outer diameter and valve diameter. If using a pressure testing machine, the pressure claws should press against this pressure plate to ensure even pressure distribution on the pressure ring on one side of the valve body.

2. When testing with a blind flange, wafer-type elastic hard-seal butterfly valves are generally tested using two flanges clamped together. For flanged elastic seat butterfly valves, sometimes users only use one flange at the bottom to bolt to the valve. In this case, the fixing bolts on the pressure ring on the valve body must bear the full pressure of the medium.

The above points are common issues encountered during installation. Understanding our valve structure will facilitate installation and ensure the correct use of the elastic hard-seal butterfly valve.

Applications and Features

The elastic seat butterfly valve utilizes a flexible stainless steel sealing ring mounted on the valve body to achieve true zero leakage:

1. Adjustable seal, leak-free for 100, 000 cycles;

2. Special sealing structure, no stress deformation under high and cold conditions, achieving zero leakage;

3.Three-dimensional eccentric structure, opening seals immediately, closing seals immediately upon contact;

4. Axial positioning device, solving the problem of easy leakage due to axial sealing surface wear; the actuator can be installed in any direction;

5. Suitable for use in clean pipelines in food, pharmaceutical, and chemical industries, as well as industrial environmental protection, water treatment, high-rise buildings, and water supply and drainage pipelines for opening, closing, or regulating the flow of media.