Stainless steel gate valve

The opening and closing part of the stainless steel gate valve is a gate plate. The movement direction of the gate plate is perpendicular to the direction of the fluid. The stainless steel gate valve can only be fully opened and fully closed, and it cannot be adjusted or throttled. The gate plate has two sealing surfaces. The two sealing surfaces of the common mode gate valve form a wedge, and the wedge angle varies with the valve parameters, usually 50, and the medium temperature is 2°52′ when the temperature is not high. Wedge stainless steel gate valve can be made into a whole, called the rigid gate; can also be made of a slight deformation of the gate to improve its craft, to make up for the deviation of the sealing surface angle in the process, this The gate is called a flexible gate. Stainless steel stainless steel gate valve material is divided into 304 stainless steel stainless steel gate valve, 316 stainless steel stainless steel gate valve, 321 stainless steel stainless steel gate valve.

The type of stainless steel gate valve can be divided into wedge gate stainless steel gate valve and parallel gate stainless steel gate valve according to the sealing surface configuration. Wedge gate stainless steel gate valve can be divided into: single gate type, double gate type and elastic gate type; parallel Gate stainless steel gate valves can be divided into single gate type and double gate type. Divided according to the position of the thread of the valve stem, it can be divided into two kinds of light stainless steel gate valve and dark stainless steel gate valve. This type of valve should generally be installed horizontally in the pipeline.
When the flanged gate valve is closed, the sealing surface can be sealed only by the medium pressure, that is, relying on the pressure of the medium to press the sealing surface of the gate plate to the valve seat on the other side to ensure the sealing of the sealing surface, which is self-sealing. Most stainless steel gate valves use forced sealing, that is, when the valve is closed, it is necessary to force the gate plate to press against the valve seat with external force to ensure the sealing of the sealing surface.

The gate of the stainless steel gate valve moves linearly along with the stem and is called stainless steel gate valve (also called stainless steel gate valve). Trapezoidal threads are usually provided on the lifting rods. The advanced nuts of the valve and the guide grooves on the valve body convert the rotation into linear motion, that is, the operating torque becomes the operating thrust.
When the valve is opened, when the lifting height of the gate is equal to 1:1 of the valve diameter, the channel of the fluid is completely open, but this position cannot be monitored during operation. In actual use, the vertex of the valve stem is used as a mark, that is, a position that does not move, as its fully open position. In order to account for temperature changes, the lock-up phenomenon usually occurs at the open-to-aperture position, and then rewinds 1/2 to 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 (ie stroke).
Stainless steel screw stainless steel gate valve

Stainless steel screw stainless steel gate valve Some stainless steel gate valve, stem nut is located on the gate plate, the hand wheel rotates to drive the valve stem to rotate, and the gate plate is lifted. Such a valve is called a rotary rod stainless steel gate valve or a dark rod stainless steel gate valve.

Manual stainless steel gate valve working principle

Turning the handwheel, the valve plate connected to the valve stem can be lifted or lowered by the advance and retreat of the thread of the handwheel and the valve stem to achieve the function of opening and closing. The stainless steel gate valve has the following advantages:
The fluid resistance is small, and the sealing surface is affected by the brushing and erosion of the medium.
Open and close more effort.
The flow direction of the medium is not limited, it does not disturb the flow or reduce the pressure.
The utility model has the advantages of simple body, short structure length, good manufacturing processability and wide application range.
The disadvantages of stainless steel gate valves are as follows:
Erosion and scratches are easily caused between the sealing surfaces, and maintenance is difficult.
Large size, opening requires a certain space, long opening and closing time.
The structure is more complicated.
The wide variety of gates can be divided into wedge gate type stainless steel gate valve and parallel gate type stainless steel gate valve according to sealing surface configuration. Wedge gate type stainless steel gate valve can be further divided into: single gate type, double gate type and elastic gate type; parallel Gate stainless steel gate valves can be divided into single gate type and double gate type. Divided according to the position of the thread of the valve stem, it can be divided into two kinds of light stainless steel gate valve and dark stainless steel gate valve.
Stainless steel gate valve installation and maintenance should pay attention to the following matters:
Handwheels, handles, and transmissions are not allowed to lift, and collisions are strictly prohibited.
The double gate stainless steel gate valve should be installed vertically (ie, the valve stem is in a vertical position with the handwheel at the top).
Stainless steel gate valves with bypass valves should open the bypass valve before opening (to balance the differential pressure at the inlet and outlet and reduce the opening force).
The stainless steel gate valve with transmission mechanism is installed according to the product manual.
If the valve is frequently used, lubricate it at least once a month.


Structural features:

The common stainless steel gate valves used on the market have been leaking or rusting for a long time. The company imported European high-tech rubber and valve manufacturing technology to produce elastic seated stainless steel gate valves, which overcomes the defects of common stainless steel gate valves such as poor sealing and rusting. The elastic seated stainless steel gate valve utilizes the elastic gate to compensate for a small amount of elastic deformation to achieve a good sealing effect. The valve has the advantages of lightness of the switch, reliable sealing, good elastic memory, and long service life. Can be widely used in tap water, sewage, construction, petroleum, chemical, food, medicine, textile, electric power, shipbuilding, metallurgy, energy systems and other body pipelines used as regulation and closure devices.

Stainless steel gate valve features

Light weight: It weighs about 20%~30% lighter than traditional stainless steel gate valves. It is easy to install and maintain.
Flat-bottom seat: traditional stainless steel gate valve is often caused by foreign objects such as stones, wood blocks, cement, iron filings, sundries, etc. deposited in the bottom of the valve groove after the water pipe is flushed, which can easily cause close leakage and water leakage. The bottom of the flexible seated stainless steel gate valve adopts the same flat design as that of the water pipe machine. It is not easy to cause debris deposition and make the fluid unobstructed.
Overall encapsulation: The gate uses high-quality rubber for internal and outsourced rubber. The European first-class rubber vulcanization technology enables the vulcanized gate to ensure precise geometric dimensions, and the rubber and spheroidal cast gates are then firmly secured and do not easily fall off. Good elastic memory. Water casting valve body: The valve body adopts precision casting. The precise geometry allows the valve body to seal the valve without any finishing.

Construction installation points

1) The installation position, height, and direction of import and export must meet the design requirements and the connection should be firm and tight.
2) All types of manual valves installed on the insulation pipe shall not be downwards.
3) Before the valve is installed, a visual inspection must be performed. The nameplate of the valve shall comply with the current standard "General Valve Marking" GB 12220. For valves with a working pressure greater than 1.0 MPa and a shut-off effect on the main pipe, strength and tightness tests shall be carried out before installation. In the strength test, the test pressure is 1.5 times the nominal pressure, and the duration is not less than 5 minutes. The valve housing and the packing should have no leakage as qualified. For the tightness test, the test pressure is 1.1 times the nominal pressure; the test pressure shall meet the requirements of GB 50243 standard for the duration of the test, and no leakage of the valve sealing surface shall be qualified.

Stainless steel gate valve has the following advantages

1. The fluid resistance is small. The sealing surface is affected by the brushing and erosion of the medium.
2, open and close more effort.
3. The flow direction of the medium is not limited, and it does not disturb the flow or reduce the pressure.
4, simple body, short structure, good manufacturing process, a wide range of applications.

The disadvantages of stainless steel gate valve are as follows

1. It is easy to cause erosion and scratches between the sealing surfaces and maintenance is difficult.
2. Large size, opening requires a certain space, long opening and closing time.
3, the structure is more complicated.
The wide variety of gates can be divided into wedge gate type stainless steel gate valve and parallel gate type stainless steel gate valve according to sealing surface configuration. Wedge gate type stainless steel gate valve can be further divided into: single gate type, double gate type and elastic gate type; parallel Gate stainless steel gate valves can be divided into single gate type and double gate type. Divided according to the position of the thread of the valve stem, it can be divided into two kinds of light stainless steel gate valve and dark stainless steel gate valve.

Technical Parameters

1. Nominal pressure: 1.0MPa, 1.6MPa, 2.5MPa
2, shell test pressure: P = 1.5PN
3. Seal test pressure: P=1.1PN
4, outlet pressure: PN1.0MPa stainless steel stainless steel gate valve 0.09 ~ 0.8MPa
PN1.6MPa stainless steel stainless steel gate valve 0.10~1.2MPa
PN2.5MPa stainless steel stainless steel gate valve 0.15~1.6MPa
5, suitable medium: water 6, applicable temperature: 0 °C ~ 180 °C

Structural features

1, the selection of materials, in line with relevant standards at home and abroad, the overall high-quality materials.
2, in line with the requirements of advanced standards at home and abroad, reliable sealing, excellent performance, beautiful appearance.
3. The seal pairing is advanced and reasonable. The sealing surfaces of the gate plate and the valve seat are made of Stellite Cobalt-based hard alloy with different hardness. The seal is reliable, high in hardness, wear-resisting, high-temperature resistant and corrosion-resistant. Excellent scratch resistance and long life.
4. The valve stem has been quenched and tempered and surface nitrided. It has good corrosion resistance, scratch resistance and wear resistance.
5. Wedge-type elastic gate structure is adopted. The medium and large diameters set the thrust bearing, the friction force is small, and it is equipped with an impact hand wheel. It is easy to open and close.
6. Various piping flange standards and flange sealing surfaces can be used to meet various engineering needs and user requirements.