Unisite Group Ltd.
Gate Valve is a opening and closing the gate assembly, perpendicular to the direction of movement and direction of flow of the gate, gate valve can be fully open and fully closed, discomfort door parameter varies, usually 5 degrees, the medium temperature is not high for 2 ~ 52 '. Improve the process, make up the sealing surface angle in the process of the deviation, which is called the gate.
Photo of our Gate Valve:
Gate valve closed, the sealing surface can only rely on media pressure to seal, that is, only rely on the media
Pressure to seal the sealing surface of the gate to the other side of the seat to ensure the sealing surface of the seal, which is self sealing. Most of the valve is forced to seal, that is, when the valve is closed, to rely on external force to force the gate to the seat, in order to ensure the sealing surface of the seal.
Movement: gate valve with the valve stem together for a straight line movement, also known as the gate valve. Usually on the lifting rod with trapezoidal thread, through the valve on the top of the nut and the body of the guide slot, the rotating motion into a linear motion, that is, the operating torque into the operating thrust. When the valve is opened, when the gate height is equal to 1:1 times the diameter of the valve, the fluid passage is completely free, but at the time of operation, the position can not be monitored. Actual use, is the apex of the stem as a sign, that is, the open position, as its fully open position. In order to consider temperature changes occur locked phenomenon, usually open to the vertex position, and then rewind 1 / 2-1 circle, as a fully open valve position. Therefore, the valve fully open position, according to the location of the gate (that is, the stroke. Some gate valve stem nut is located on the gate, the hand wheel rotation to drive the valve stem rotation, and so that the gate to upgrade, this valve is called the rotating rod gate valve or called the dark bar gate valve.
Domestic production of more than a number of manufacturers, the size of the connection is mostly not uniform. Mainly divided into the following categories: JB/T2203 - 1999 "gate structure length" of the general category. At present, most of the domestic safety valve manufacturers are in accordance with the standard design and production.
Manual gate valve working principle: turn the hand wheel, through the hand wheel and the stem of the thread into the back, enhance or decrease the valve plate connected with the stem, to achieve the role of opening and closing.
According to the shell / main material classification, gate valve can be divided into:
Metal material valve: such as carbon steel valves, alloy steel valves, stainless steel valves, cast iron valves, titanium valves, Monel valves, copper alloy valves, lead alloy valves.
Metal body lining valves: such as rubber lined valves, fluorine lined valves, lined with lead valves, plastic lined valves, lined with enamel valves.
Non metallic materials, such as ceramic valves, glass valves, plastic valves.
1, flow resistance is small. Body internal media channel is through, the media into a straight flow, flow resistance is small.
2, open and close when more effort. Is compared with the cut-off valve, because whether it is open or closed, the direction of movement of the gate and the direction perpendicular to the media flow.
3, a high degree of large, open and close for a long time. The opening and closing of the gate is larger, and the reduction is carried out through the screw.
4, water hammer phenomenon is not easy to produce. The reason is that the closure time is long.
5, medium can flow in any direction on both sides, easy to install. Gate valves are symmetrical on both sides of the channel.
6, the structure of the length (the distance between the two connecting end of the shell) is small.
7, the form is simple, the structure length is short, the manufacture craft is good, the scope of application is wide.
8. The structure is compact, the valve is rigid, the passage is smooth, the flow resistance is small, the sealing surface is made of stainless steel and hard alloy, and the service life is long, the sealing is reliable, the operation is light and flexible.
the sealing surface is easy to cause erosion and abrasion, maintenance is more difficult. Larger size, open requires a certain space, open and close for a long time. More complex structure.
Valve types: according to the sealing surface configuration can be divided into wedge gate valve and parallel gate valve, wedge gate valve and is divided into: single gate type, dual gate plate and the flexible gate type; parallel gate valve can be divided into single gate plate and dual gate plate. According to the screw position of the valve stem can be divided into two kinds of the bright and dark bar gate valve.
Structure characteristics: general valve market has long been used widespread leakage or rusting phenomenon, the introduction of European high-tech rubber and valve manufacturing technology to produce elastic valve seat seal, valve seal to overcome the generally poor, rust and other defects, flexible seat seal gate valve with flexible gate generate tiny elastic deformation of compensation function to achieve a good sealing effect, the valve with a switch to compact, reliable sealing, elastic memory is good, and the use of life and other significant advantages. Can be widely used for water, sewage, construction, petroleum, chemical industry, food, pharmaceutical, textile, electric power, shipbuilding, metallurgy, energy systems, a body of pipeline regulation and closure devices as.