The opening and closing parts of the gate valve are the gate plate. The movement direction of the gate plate is perpendicular to the direction of the fluid. Sealing face has two gate, two of the most commonly used mode gate valve sealing surface form a wedge, the wedge Angle vary with the valve parameters, usually in the form of 50, when the medium temperature is not high for 2 ° 52 '. Wedge gate valve gate plate can be made into a whole, called rigid gate plate; It can also be made into a slightly deformed gate, called an elastic gate, to improve its technology and make up for the deviation of the sealing surface Angle during processing

The types of gate valves can be divided into wedge gate valves and wedge gate valves according to the sealing surface configuration. Wedge gate valves can also be divided into single gate valve, double gate valve and elastic gate valve. Parallel gate valves can be divided into single and double gate valves. According to the position of the screw thread of the stem, it can be divided into two types: open stem gate valve and dark stem gate valve. Gate valve is closed, sealing surface can only rely on medium pressure to seal, that depend on medium pressure, the disc will be to the other side of the valve seat sealing surface pressure to ensure that the seal face seal, this is the seal. Most gate valves are hermetically sealed, that is, when the valve is closed, it must rely on external force to force the gate to the seat to ensure the sealing of the sealing surface.

The gate plate of a gate valve moves in a straight line along with the stem. Generally, there are trapezoid thread on the lifting rod. Through the nuts on the top of the valve and the guide groove on the valve body, the rotary motion is changed into linear motion, that is, the operating torque is changed into operating thrust.

When the valve is opened, the flow channel is completely unblocked when the height of the gate lift is equal to 1:1 of the valve size, but this position cannot be monitored during operation. In practical use, the top of the stem as the mark, that is, the position of the immovable valve, as its full open position. In order to take account of the temperature change, the lock occurs, usually at the opening to the peak position, and then back 1/2 to 1 lap, as the position of the full open valve. Therefore, the full open position of the valve shall be determined by the position of the gate (i.e. > stroke). Some gate valves, stem nuts on the gate plate, hand wheel rotation drive stem rotation, and raise the gate, this valve is called rotating stem gate valve or dark stem gate valve.

Gate valves have the following advantages

1. The fluid resistance is small, and the sealing surface should be greeted and eroded by the medium.

2. It is easier to open and close.

3. The flow direction of media is unrestricted, without disturbing the flow and without reducing pressure.

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

The disadvantages of gate valves are as follows:

1. The sealing surface is easy to cause erosion and abrasion, and maintenance is difficult.

2. The external size is large, which requires a certain space to open and close for a long time.

3. Complex structure.

The installation and maintenance of gate valves shall pay attention to the following matters: 1. Handwheel, handle and drive mechanism are not allowed to be hoisted, and collision is strictly prohibited. 2. Double gate gate valves shall be installed vertically (i.e. the stem is in the vertical position and the handwheel is at the top). 3. Gate valves with bypass valve should open bypass valve before opening (to balance pressure difference between inlet and outlet and reduce opening force). 4. The gate valve with drive mechanism shall be installed according to the specifications of the product operating instructions. 5. If the valve is frequently switched on and off, lubricate at least once a month.

Seal gate valves of the elastic base seat features: use on the market for a long time there is a widespread leaks or general gate rusty phenomenon, the company introduced the European high-tech rubber and valve manufacturing technology of elastic seat seal gate valves, overcome the general gate seal bad, rust and other defects, seal gate valves of the elastic base seat using elastic disc produce elastic deformation compensation effect to achieve good sealing effect, this valve has the switch light, reliable sealing, good elastic memory and the service life and other significant advantages.