What is a Pressure Self-Sealing Gate Valve?

1.Pressure self-sealing gate valve

It is mainly suitable for cutting off or connecting the pipeline medium in various systems of thermal power plants. Applicable medium: non-corrosive media such as water and steam. Compared with other valve products, power station valves are characterized by high temperature and high pressure, unique self-sealing design, the higher the pressure, the more reliable the seal.

It uses the pressure of the medium itself to achieve the purpose of sealing. The greater the pressure, the greater the sealing force, and the more reliable the sealing. The sealing surface is welded with drill-based cemented carbide, and the processed pure metal layer is ≥3mm, which has abrasion resistance, high-temperature resistance, corrosion resistance, scratch resistance, and long service life. It is suitable for the pipelines of high-temperature and high-pressure water in thermal power plants, petrochemical, metallurgy, etc., and high-temperature and high-pressure water, steam, oil, and superheated steam in metallurgy.

2.Principle:

The gate plate of the pressure self-sealing gate valve moves linearly with the valve stem. Usually, there is a trapezoidal thread on the lifting rod. Through the nut at the top of the valve and the guide groove on the valve body, the rotary motion is changed into linear motion, that is, the operation is turned. The moment becomes the operating thrust. When the valve is opened, when the lifting height of the gate is equal to 1:1 times the valve diameter, the fluid passage is completely unblocked, but this position cannot be monitored during operation. In actual use, the apex of the valve stem is used as the mark, that is, the unmovable position, as its fully open position. In order to take into account the locking phenomenon caused by temperature changes, it is usually opened to the apex position, and then back 1/2-1 turn, as the position of the fully open valve. Therefore, the fully open position of the valve is determined by the position of the gate.

3.Features:

1. The fluid resistance is small, and the sealing surface is less brushed and corroded by the medium.

2. It saves effort to open and close.

3. The flow direction of the medium is not restricted, does not disturb the flow, and does not reduce the pressure.

4. Simple shape, short structure length, good manufacturing technology, and wide application range.

5. Unique self-sealing design, the higher the pressure, the more reliable the sealing.

4.Structural features:

1. Adopting a straight-through structure with a flow channel, which greatly reduces the flow resistance coefficient and energy loss, and significantly improves the service life and performance of the valve.

2. The middle cavity of the valve adopts a pressure self-tight sealing structure with good sealing performance.

3. The sealing surface of the gate and the valve seat is made of hard alloy surfacing, which has good wear resistance, high-temperature resistance, corrosion resistance and scratch resistance.

4. The surface of the valve stem is treated with corrosion-resistant nitriding, which has good corrosion resistance and scratch resistance.

5. The structure of the opening and closing parts can be designed into different forms such as single plate, double plate, parallel double plate, etc. according to user requirements.

6. Equipped with a multi-turn electric device, which can realize remote control and local operation.

The above information is provided by the gate valve supplier.