The opening and closing part of the gate valve is the wedge, the movement direction of the gate valve is perpendicular to the fluid direction, the gate valve can only be fully opened and closed, but cannot be adjusted and throttled. Wedge gate valve can be made into a whole, called solid wedge; It can also be made into a wedge that can produce a small amount of deformation, so as to improve its process ability and make up for the deviation of sealing surface angle in the processing process, this kind of wedge is called flexible wedge. When the gate valve is closed, the sealing surface can only be sealed by the medium pressure, that is, the sealing surface of the gate valve is pressed to the valve seat on the other side by the medium pressure to ensure the sealing of the sealing surface, which is self sealing. Most gate valves are forced to seal, that is, when the valve is closed, the gate should be forced to the valve seat by external force, so as to ensure the tightness of the sealing surface.

Gate valve wedge with the stem together for linear movement, known as lifting stem gate valve, also known as rising stem gate valve. Generally, there are trapezoidal threads on the lifting rod. Through the nut 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, when the lifting height of the ram is equal to 1:1 of the valve diameter, the fluid channel is completely unblocked, but in operation, this position cannot be monitored. In actual use, the apex of the valve stem is used as the mark, that is, the position that can not be opened is used as its full open position. In order to consider the lock phenomenon of temperature change, usually in the open to the top position, and then back 1 / 2-1 circle, as the position of full open valve. Therefore, the full open position of the valve is determined by the position of the ram, that is, the travel. Some gate valves, stem nut is set on the wedge, hand wheel rotation drives the stem to rotate, so that the wedge is lifted, this kind of valve is called rotating stem gate valve, or Non rising stem gate valve.

According to the sealing surface configuration, gate valve can be divided into wedge gate valve and parallel gate valve, and wedge gate valve can be divided into single gate plate, double gate plate and elastic gate valve; Parallel gate valve can be divided into single gate plate and double gate plate. According to the thread position of the stem, it can be divided into two types: rising stem gate valve and Non rising stem gate valve.

The main advantages of ball valve are as follows:

1. The flow resistance is small, the medium channel inside the valve body is straight, the medium flows in a straight line, and the flow resistance is small.

2. It is easy to open and close, compared with the stop valve, because whether it is open or closed, the movement direction of the wedge is perpendicular to the flow direction of the medium.

3. High height, long opening and closing time, the opening and closing stroke of the wedge is large, and the lowering is carried out through the screw.

4. The medium can flow to both sides in any direction, easy to install. Both sides of gate valve passage are symmetrical.

5. The structure length (the distance between the two connecting ends of the shell) is small.

6. It has the advantages of simple shape, short structure length, good manufacture ability and wide application range.

7.The valve features compact structure, good rigidity, smooth passage, small flow resistance, stainless steel and cemented carbide sealing surface, long service life, PTFE packing, reliable sealing, light and flexible operation

STAVAL provides high performance gate valve products, including Wedge gate valve, Pressure seal gate valve, Knife gate valve, Flat gate valve and Bellow seal gate valve.

Good Service, Better Price, Best Quality, by Xiamen Staval Valve Technology Co.,Ltd