chinese Archives

Driving device for Manual Wafer Butterfly Valve

August 31, 2022

The driving device of the manual wafer butterfly valve is mainly the handwheel and the handle. For valves with little torque required for opening and closing, a manual device, handwheel or handle can be used to directly fix the valve stem or valve stem nut. The diameter of the handwheel is based on the relevant standards or the torque required for valve opening and closing. According to the standard, the opening and closing force added to the handwheel or handle cannot exceed 360N, and its shape and size can be in accordance with the provisions of JB/T93-2008. Steel plate, aluminum alloy or plastic pressed handwheels can also be used on manual wafer butterfly valves with smaller nominal size DN. The butterfly valve also has a remote-operated manual device using a universal joint.

JIS 10K-wafer butterfly valve-backup seat (3)

Manual Wafer Butterfly Valve Handle and Turbine Drive
The handle of the manual wafer butterfly valve is mainly used with the gear, while the handwheel needs to be used with the worm drive. When the operating force of the valve exceeds 360N, cylindrical spur gears, bevel gears and worm drive devices are often used to reduce the force required for opening and closing. What’s the difference between a handle and a turbo? The first is that the driving method is different. The turbine butterfly valve mainly drives the rotation of the internal gear through the rotation of the handwheel, so that the valve plate rotates and the valve plate is opened and closed. The handle butterfly valve mainly uses the rotation of the handle to turn the valve plate to open and close. Secondly, the force required to operate the handle is large, so the diameter of the valve used is generally below 250mm. Therefore, the handle of the manual wafer butterfly valve and the turbine drive are also different in nominal diameter.

Operating procedures for the drive device of the manual wafer butterfly valve
1. The operator should be familiar with the structure and working principle of the manual butterfly valve.
2. The opening force of the manual butterfly valve exceeds 15kg. If you feel particularly strenuous, you should eliminate the product failure.
3. When the manual butterfly valve is closed, the handle should be reversed for one or two turns, which is conducive to the reopening of the manual butterfly valve.
4. There will be a sediment accumulation area near the manual butterfly valve that is closed for a long time, and these sediments will form resistance to the opening and closing of the manual butterfly valve.
5. When opening, the opening and closing actions should be repeated to promote the loosening of the sediment.
6. If it is found that there is often sediment deposition near the manual butterfly valve, the manual butterfly valve should be opened and closed frequently to facilitate the removal of sediment.
7. For the manual butterfly valve that does not open and close for a long time, it should also be operated once or twice regularly to prevent rust or silt.
8. Check the shaft end for leakage every six months. If there is leakage, replace the packing in time.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Where can butterfly valves be used

August 22, 2022

The butterfly valve is a kind of valve used to control the fluid flow in the pipeline. It uses the disc-shaped butterfly plate as the opening and closing part, and rotates 0~90° reciprocatingly to realize the opening and closing of the butterfly valve. Butterfly valves are used in a wide

Double flange butterfly valve (16)

range of applications. In general, butterfly valves are suitable for various water fluids, including domestic water, fire water, circulating water, sewage, etc. Some powder material media can also use butterfly valves. This article will introduce you where butterfly valves can be used.
Butterfly valve has two obvious characteristics, large diameter and low pressure difference. Compared with other types of valves, under the premise of the same diameter, the butterfly valve is lighter in weight, smaller in volume, and has the simplest structure, and this advantage will become more obvious as the diameter increases. The cost of using butterfly valves is relatively low. The pressure bearing capacity of the butterfly valve is poor. The greater the pressure of the working conditions, the greater the damage to the sealing surface of the butterfly valve, and the technical requirements and manufacturing costs of the butterfly valve will also increase significantly.

Butterfly valves are usually used to control the flow on large-diameter pipelines, and gate valves, globe valves or ball valves are not suitable. Imagine that on a DN1500 pipeline, if a gate valve or globe valve is used, the valve needs to be made very large and takes up a lot of space, while the ball valve is not suitable for large-diameter valves. Although butterfly valves can also be used for flow regulation, in small-diameter pipelines, butterfly valves are rarely used for flow regulation. One is because it is not easy to adjust, and the other is the sealing performance of butterfly valves and globe valves and ball valves. Compared with the poor, the gate valve cannot do flow regulation. Small-diameter butterfly valves are generally used in pipelines that pass through water, such as water supply and drainage, circulating water, fire water, etc. In addition, butterfly valves are often used in places where the requirements for sealing are not particularly high, and the frequency of opening and closing is not particularly frequent.

The above is the introduction of “where the butterfly valve can be used”. The butterfly valve plays a very important role and has become an indispensable control component in our daily production work. If you have purchase requirements for butterfly valve products, you are welcome to inquire Tanghai Valve.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Advantages and Disadvantages of Centerline Butterfly Valves

August 16, 2022

Advantages of Centerline Butterfly Valves
The centerline butterfly valve adopts the centerline sealing structure, and the centerline of the disc sealing of the butterfly valve is consistent with the centerline of the valve body and the rotation centerline of the valve stem. The upper and lower ends of the butterfly plate near the

Double flange butterfly valve (16)

valve stem are designed as two smooth planes, and are in close contact with the valve seat gasket made of rubber to ensure that the medium does not leak from both ends; the outer edge of the butterfly plate is designed as a spherical outer edge, It should be ensured that the arc surface has a suitable surface roughness during processing, and the seat gasket should ensure that the sealing surface has a suitable surface roughness during molding. When the valve is closed, the butterfly plate rotates 0-900 degrees, and gradually compresses the valve seat gasket made of rubber, so that the elastic force formed by the elastic deformation of the valve seat gasket is used as the necessary sealing pressure to ensure the sealing of the valve.
The centerline butterfly valve is designed to reduce flow resistance:
1) The channel is designed as a full-diameter structure, which ensures the flow area of the valve and reduces the flow resistance when the fluid passes through the valve.
2) The butterfly plate adopts the disc-shaped streamline design, which can not only ensure the stress intensity in the center of the butterfly plate, but also ensure that the valve can obtain a larger flow coefficient and a smaller fluid resistance coefficient.
3) The valve seat sealing ring is designed as a soft sealing structure of rubber and resin skeleton (fixed sleeve), which is embedded in the valve body after being manufactured. The part of the inner ring higher than the inner cavity of the valve body adopts a streamline design to achieve the purpose of reducing the flow resistance.

Disadvantages of Centerline Butterfly Valves
Because of its own structure, the centerline butterfly valve can only be made into a soft-sealed butterfly valve, so the centerline butterfly valve can only be used in the working environment of low pressure and normal temperature, and is not suitable for high temperature and high pressure conditions.
The above is the introduction of the advantages and disadvantages of the centerline butterfly valve

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Installation and operation method of manual butterfly valve

August 8, 2022

The most common driving methods for butterfly valves are manual, pneumatic, hydraulic and electric. This article mainly introduces the manual butterfly valve. Manual butterfly valve can be subdivided into handle butterfly valve and turbine butterfly valve. The two have no major impact on the installation of manual butterfly valves, and the difference lies more in the operation and use.

JIS 10K-wafer butterfly valve-backup seat (2)

Installation precautions for manual butterfly valve
1. Before installing the manual butterfly valve, it is necessary to first confirm whether the product is suitable for the working conditions of the medium in the pipeline. The interior of the butterfly valve must be clean, including the sealing ring, valve shaft, and butterfly plate. There must be no foreign matter. Do not close the butterfly plate before cleaning the butterfly valve to prevent damage to the sealing ring.
2. The wafer type manual butterfly valve needs to use the special flange for butterfly valve during installation.
3. It is best to install it vertically on the pipeline, not upside down.
4. When it is necessary to adjust the flow, it is recommended to use a turbine butterfly valve.
5. After installation, every part of the valve should be checked regularly during use, and faults should be eliminated in time.

How to operate a manual butterfly valve
From the above, we know that manual butterfly valves are divided into handle butterfly valves and turbo butterfly valves, and their operation methods will of course be different. The operation of the handle butterfly valve is to pull the handle, turn it counterclockwise to open the valve, and turn it clockwise to close the valve. The turbine butterfly valve is to install a worm gear reducer on the valve stem of the butterfly valve. The turbine device makes the operation of the butterfly valve more labor-saving, copes with a larger medium pressure environment, and also improves the operability of the valve.
If the diameter of the butterfly valve is less than 150mm, it is recommended to use the handle to drive it. If the diameter of the butterfly valve exceeds 150mm, it is recommended to use the turbine device, which is more labor-saving to operate. The maximum diameter of the handle butterfly valve can only be 250mm. If it exceeds this maximum diameter, it is no longer applicable and needs to be equipped with an electric or pneumatic actuator.
In industrial engineering, we recommend the use of turbo butterfly valves, because in addition to saving labor, turbo butterfly valves have better sealing performance than handle butterfly valves. Another point is that in the pipeline with high switching frequency, the service life of the turbine butterfly valve is higher than that of the handle butterfly valve.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Stem structure and Integral Seat of centerline wafer butterfly valve

July 25, 2022

The centerline wafer butterfly valve can be divided into two types: pinless butterfly valve and pinned butterfly valve. The main difference between them is whether the valve plate and valve stem are fixed with pins. The pinned butterfly valve and the pinless butterfly valve

JIS 10K-wafer butterfly valve-backup seat (1)

correspond to the needs of different working conditions, and more depends on the needs of users. Because the process of the pinless butterfly valve is more effective and more complicated, and there is no pin hole on the surface of the butterfly plate, its price will also be a little more expensive than that of the butterfly valve with a pin. And relatively speaking, it does not appear pitting corrosion and point leakage. Now let’s take a look at the pinless structure of the centerline wafer butterfly valve:

Centerline Wafer Type Butterfly Valve Double Half Shaft Structure
The double half shaft is a kind of structural performance of the midline wafer butterfly valve, also called the square shaft. Corresponding to it is the through shaft. Double semi-shaft means that there is a shaft on the upper and lower sides of the valve plate of the butterfly valve. The upper shaft and the valve stem are integrally formed to act as a transmission, and the lower shaft is a circular shaft, which plays the role of positioning the valve plate. Since the connection between the upper shaft, the valve stem and the valve plate is usually through a square shaft – a square hole, there are also hexagonal connections. Therefore, the processing of the valve plate is usually processed by punching, slotting or EDM, and the processing efficiency is low. In addition, the lower shaft also needs to pass through the through hole at the bottom of the valve body to be installed. After that, a gasket and a retaining ring need to be added to the bottom to fix the lower shaft. The processing and assembly of the valve body also increases the difficulty. Therefore, this structure is only used in large sizes now.

Large and small head shaft structure of centerline wafer butterfly valve
The stem of this midline wafer type butterfly valve is a flat shaft that passes through the valve plate. At the lower end, the diameter is reduced to a size smaller than the flat hole of the valve plate to pass through the valve plate, and the bottom of the valve body is positioned to ensure the valve Concentricity and symmetry of the plate. The processing of the through hole of the valve plate only requires a high degree of coaxiality of the single-side feed. In addition, there is no through hole at the bottom of the valve body, which also avoids external pollution caused by the leakage of the valve body. However, due to the variable diameter of the valve stem and the valve body, the processing cost is appropriately increased, and the upper and lower holes of the valve seat are not of equal diameter, which is easy to cause errors in the assembly process.

Equal Diameter Flat Shaft for Centerline Wafer Type Butterfly Valve
The structure of this midline wafer butterfly valve is evolved from the structure of the large and small head shafts. The valve stem is an equal-diameter shaft. The bottom is processed into double D type and the valve plate forms a close fit to ensure the transmission of the valve plate. It is also a flat hole, but the direction of the flat hole is rotated by a 90°, so as to ensure that when the valve is at the closing point or close to the closing point, the valve stem is in contact with the valve body bushing with a circular surface to ensure the symmetry of the valve plate and the same The axial degree can not only avoid the bending deformation of the valve stem but also make the valve close tightly. Since the valve body and seat are the same size in both directions, the efficiency can be greatly improved during processing and assembly. This kind of structure is simple and practical, and has the characteristics of high processing efficiency, quick assembly, tight coordination, economical saving and so on.

We all know that the seal of the centerline wafer butterfly valve is inseparable from the sealant sleeve, and the integral sealant sleeve is actually a wafer-type butterfly valve with a reliable sealing and leak-proof valve seat. It includes the annular valve body of the upper and lower valve necks, the annular valve seat embedded on the inner wall of the valve body, the butterfly plate, and the valve body which is rotatably installed on the valve body through the valve seat and the butterfly plate through the upper and lower valve necks. The valve stem and the transmission device, the valve seat is composed of an annular skeleton and an integral sealant sleeve formed integrally with it.

The integral sealant sleeve of the midline wafer butterfly valve consists of an inner wall sealant layer covering the inner wall of the skeleton and an end face sealant layer covering the two ends of the skeleton respectively. It is characterized in that the two end-face sealant layers are divided into a circumferential extension edge covering the end face of the annular valve body, and the extension edge of one end-face sealant layer is integrally and fixedly connected with the end-face sealant layer. The fixed epitaxial edge of the end face sealant layer on the other side and the end face sealant layer are detachably connected movable epitaxial edges.

The birth of this midline wafer butterfly valve seat is that the butterfly valve, as a fluid pipeline valve, has very strict requirements on its tightness. However, the current wafer butterfly valve still has the problem of running and dripping, which affects the normal use. Therefore, how to improve the structure of the valve seat has become a concern. However, the integral sealing valve seat, which is reliably sealed against leakage, can completely cover and seal the joint between the valve seat and the annular inner wall of the valve body. Therefore, it can effectively prevent the fluid in the pipeline from entering the valve body, effectively avoid the leakage of the valve caused by engineering construction and other reasons, and ensure the normal operation of the valve. In addition, the structure of the fixed epitaxial edge and the movable epitaxial edge is also convenient to assemble and use. While ensuring the quality of the project, it saves costs and is suitable for market promotion.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Stem structure of centerline wafer butterfly valve

July 11, 2022

The centerline wafer butterfly valve can be divided into two types: pinless butterfly valve and pinned butterfly valve. The main difference between them is whether the valve plate and the valve stem are fixed with a pin. The pinned butterfly valve and the pinless butterfly valve

JIS 10K-wafer butterfly valve-backup seat (3)

correspond to the needs of different working conditions, and more depends on the needs of users. Because the process of the pinless butterfly valve is more effective and more complicated, and there is no pin hole on the surface of the butterfly plate, its price is also a little more expensive than that of the butterfly valve with a pin. And relatively speaking, it does not appear pitting corrosion and point leakage. Now let’s take a look at the pinless structure of the centerline wafer butterfly valve:

Centerline Wafer Type Butterfly Valve Double Half Shaft Structure
The double half shaft is a kind of structural performance of the midline wafer butterfly valve, also called the square shaft. Corresponding to it is the through shaft. Double semi-shaft means that there is a shaft on the upper and lower sides of the valve plate of the butterfly valve. The upper shaft and the valve stem are integrally formed to act as a transmission, and the lower shaft is a circular shaft, which plays the role of positioning the valve plate. Since the connection between the upper shaft, the valve stem and the valve plate is usually through a square shaft – a square hole, there are also hexagonal connections. Therefore, the processing of the valve plate is usually processed by punching, slotting or EDM, and the processing efficiency is low. In addition, the lower shaft also needs to pass through the through hole at the bottom of the valve body to be installed. After that, it is necessary to add a gasket and a retaining ring to the bottom to fix the lower shaft. The processing and assembly of the valve body also increases the difficulty. Therefore, this structure is only used in large sizes now.

Large and small head shaft structure of centerline wafer butterfly valve
The stem of this midline wafer butterfly valve is a flat shaft that passes through the valve plate. The diameter at the lower end is reduced to a size smaller than the flat hole of the valve plate to pass through the valve plate, and the bottom of the valve body is used for positioning to ensure the valve Concentricity and symmetry of the plate. The processing of the through hole of the valve plate only requires a high degree of coaxiality of the single-side feed. In addition, there is no through hole at the bottom of the valve body, which also avoids external pollution caused by the leakage of the valve body. However, due to the variable diameter of the valve stem and the valve body, the processing cost is appropriately increased, and the upper and lower holes of the valve seat are not of equal diameter, which is also prone to errors in the assembly process.

Equal Diameter Flat Shaft for Centerline Wafer Type Butterfly Valve
The structure of this midline wafer butterfly valve is evolved from the structure of the large and small head shafts. The valve stem is an equal-diameter shaft. The bottom is processed into double D type and the valve plate forms a close fit to ensure the transmission of the valve plate. It is also a flat hole, but the direction of the flat hole is rotated by a 90°, so as to ensure that when the valve is at the closing point or close to the closing point, the valve stem is in contact with the valve body bushing with a circular surface to ensure the symmetry of the valve plate and the same The axial degree can not only avoid the bending deformation of the valve stem but also make the valve close tightly. Since the valve body and seat are the same size in both directions, the efficiency can be greatly improved during processing and assembly. This kind of structure is simple and practical, and has the characteristics of high processing efficiency, quick assembly, tight coordination, economical saving and so on.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

wafer type single plate swing check valve manufacturer

April 15, 2022

Our company specializes in the production of wafer type single plate check valve, stainless steel single disc check valve, aluminum bronze single plate check valve, etc. The price is favorable and the quality is stable. Specializing in the production of valves for 16 years.

wafer type, single disc swing check valve (3)

Single-plate check valve is an ultra-thin check valve with short structure size and single disc design. Compared with the traditional swing check valve, this series of valves has no external leakage, can be installed at any position, Good sealing performance, low linear vibration, low pressure drop and zero seat ring wear advantages.
Product name: Single plate check valve
Product model: H74H, H74W, H74X
Nominal diameter: DN50～DN1000
Structural form: single flap swing
Nominal pressure: 1.6MPa～4.0MPa
Connection method: Wafer type
Applicable temperature: -29ºC～+425ºC
Drive Mode: Media Push
Body material: cast steel, stainless steel, aluminium bronze, …
Standard: National standard GB, German DIN, American API, ANSI
Applicable medium: water, oil, steam, gas, liquid
Manufacturer: Tanghai valve

ALB Single plate check valve

Product description of single plate check valve:
H74H, H74W, H74X single-plate check valve is an ultra-thin check valve with short structure size and single disc design. Compared with the traditional swing check valve, this series of valves has no external leakage, Can be installed in any position, good sealing performance, low linear vibration, low pressure drop and zero seat ring wear advantages.
The working principle of single plate check valve:
The single-plate check valve is a disc type ultra-thin check valve. The disc is attached with an O-ring seal, which has good sealing performance, and is assisted by a spring to close, and the action is sensitive. It is especially suitable for places with limited installation space. It has the advantages of simple structure, beautiful appearance, light weight and convenient installation. It is mainly suitable for water supply system, petroleum, chemical industry, metallurgy and other industrial sectors. It is most suitable for places with limited installation space.
Product features of single plate check valve:
1. The structure is very short in length, small in size and light in weight, which brings great convenience to the installation, handling and storage of pipes for the valve, and can save a lot of materials and reduce costs.
2. The valve is an integral structure, simple and compact, the impact force is small when the valve is closed, the water hammer pressure is small, the valve life is long, and the reliability is high.
3. It can be installed horizontally or vertically, and it is light in weight, and it is not necessary to set a support for the valve.
4. The flow channel is smooth, the fluid resistance is small, and the valve disc can be fully opened under a small pressure difference.
Performance parameters of single plate check valve:

Code	Pressure（MPa）	Temp（℃）	Medium	Body material
H74X-10C/16C/25C	1.0～2.5	－29～80	Water, Oil	CS /SS /ALB
H74H-10C/16C/25C/40C	1.0～4.0	－29～425	Water, Oil, Gas	CS /SS /ALB
H74W-10P/16P/25P/40P	1.0～2.5	≤150	Nitric acid	SS
H74Y-40P	4.0	≤150	Nitric acid	SS

Outline structure diagram and main dimensions:

video of wafer type single disc swing check valve:

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

What are the advantages of gate valves-resilient & metal seated

April 15, 2022

The gate valve has an opening and closing gate. The movement direction of the gate is perpendicular to the direction of the fluid. The gate valve can only be fully opened and fully closed, and cannot be adjusted or throttled. The gate

DN1000-DIN-F5-NRS gate valve-IS&Y (6)

valve is sealed by the contact between the valve seat and the gate plate. Usually, the sealing surface will be surfacing with metal materials to increase wear resistance, such as surfacing 1Cr13, STL6, stainless steel, etc. The gate has a rigid gate and an elastic gate. According to the different gates, the gate valve is divided into a rigid gate valve and an elastic gate valve.
Gate valve is a kind of valve with a large number of consultations every day. It is often used in water supply systems. The advantages of gate valves are:
1. Small flow resistance. The medium channel inside the valve body is straight, and the medium flows in a straight line. When the gate is fully opened, the internal resistance of the valve body channel is almost zero, and the flow resistance is very small.
2, opening and closing labor-saving. Whether the gate valve is open or closed, the movement direction of the gate is perpendicular to the flow direction of the medium, and the resistance of the gate to the lifting movement is also very small, and it is very labor-saving to open and close.
3. The full opening and full closing of the gate valve requires a long stroke, and the closing time is relatively long, which also makes the water hammer phenomenon less likely to occur.
4. The two sides of the gate valve channel are symmetrical, and the installation is not restricted by the flow direction of the medium, which is convenient for installation.
5. The shape is simple, the length of the structure is short, the manufacturing process is good, and the scope of application is wide.
6. Wide range of uses, gate valves are made of gray cast iron, ductile iron, cast steel, stainless steel, forged steel and other materials. Different materials can be used in different working conditions and environments, and have a wide range of applications.
Precautions for installation and use of gate valve
1. The handwheel, handle and transmission mechanism are not allowed to be used for lifting, and collision is strictly prohibited.
2. The double gate gate valve should be installed vertically (that is, the valve stem is in the vertical position and the handwheel is at the top).
3. The gate valve with bypass valve should open the bypass valve before opening (to balance the pressure difference between the inlet and outlet and reduce the opening force).
4. The gate valve with transmission mechanism shall be installed according to the provisions of the product instruction manual.
5. If the valve is frequently switched on and off, lubricate it at least once a month.
6. The gate valve is only used to fully open and fully close the medium on various pipelines or equipment, and is not allowed to be used for throttling.
7. For gate valves with handwheels or handles, auxiliary levers should not be added during operation (if the sealing is not tight, the sealing surface or other parts should be checked and repaired). Turn the handwheel and handle clockwise to close, and vice versa. The gate valve with transmission mechanism should be used in accordance with the stipulations in the product instruction manual.

gate valve (3)

The difference between a metal seated gate valve and a resilient seated gate valve:

What are the differences between hard sealing gate valves and soft sealing gate valves? This article will introduce you.

material difference:
The material of the hard sealing gate valve body is mainly cast steel, stainless steel and forged steel. The gate plate and internal flow channel seal are all made of Stellite alloy accumulation welding.
The material of the soft-sealed gate valve body is mostly cast iron, the valve plate is covered with rubber, the appearance of the soft-sealed gate valve, and the valve wall of the flow channel side are all sprayed with electrostatic powder. Not only is the appearance beautiful, but more importantly, the smoothness of the flow channel and the inner valve wall ensures that the rubber-lined gate will not be affected by the roughness of the inner valve wall when opening and closing.

difference in use:
Soft-sealed gate valve is suitable for non-corrosive gas-liquid medium at normal temperature (≤80℃). Such as water, air, oil, water treatment sewage and other pipelines. And has a good sealing effect, almost zero leakage can be achieved.
The hard-sealed gate valve is suitable for high temperature (≤425℃) with slightly corrosive gas and liquid. Such as steam, heat transfer oil, sewage, petroleum, chemical industry, metallurgy, pipeline. Can have a certain degree of wear resistance.

To sum up, the difference between a soft-sealed gate valve and a hard-sealed gate valve is that the sealing performance of the soft-sealed gate valve is better than that of the hard-sealed gate valve, but the temperature and wear resistance of the hard-sealed gate valve is better than that of the soft-sealed gate valve. Each has advantages and disadvantages.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Video of resilient seated gate valve:

Principle and Maintenance of Silence Check Valve

April 12, 2022

Silence check valve, also called silent check valve, muffler check valve.

The principle of silent check valve:
The silent check valve is an automatic valve, which realizes the opening and closing of the valve flap by relying on the pressure of the medium flow. When the medium flows through the valve body, the valve flap is pushed open by the

silent check valve (9)

medium pressure, the valve is opened, and the medium flows through. When the medium stops flowing, the valve disc loses pressure and automatically closes, and blocks the backflow of the medium. The purpose of the muffler check valve is to prevent the backflow of the medium in the water supply and drainage system and the high-rise building pipe network system, to prevent the reverse rotation of the pump and the driving motor, and the discharge of the container medium.

silent check valve features:
1. The design of the valve disc is modeled after the “bullet head”, and the design of the valve body is modeled after the “waist drum”, which not only improves the flow direction of the medium, but also reduces the fluid resistance and the flow resistance coefficient.
2. The silent check valve is small in size and low in price. The structure is short and compact, and a non-metallic lubricating sleeve is installed between the guide shaft and the guide frame, which improves the flexibility of the valve disc movement, is not easy to cause locking, and can effectively eliminate the noise caused by the impact of the valve disc.
3. The skeleton rubber sealing ring is inlaid on the valve body, which avoids the direct erosion of the sealing ring by the medium and prolongs the service life of the sealing ring.
4. The opening and closing strokes of the valve disc are short, which can prevent the occurrence of water hammer.
5. The application field of silencing check valve is generally installed at the outlet of the pump in suitable drainage system and high-rise building pipe network system. In addition, the valve is not suitable for installation and use in the sewage pipe network.

The maintenance and maintenance of the silent check valve are as follows:
1) The opening and closing parts should be in the closing device during storage and transportation, and the following work should be done at the same time:
①The flap of the silent check valve should be fixed in the open position.
②The inner openings at both ends of the diameter are blocked with foam boards, and the ports must be plugged with stuffy caps to prevent dust and rust, and keep the channel clean and the end surface flat;
③ Appropriate packaging protection, shockproof and anti-collision shall be carried out for the cylinder part;
2) The silent check valve should be placed smoothly, with the pneumatic drive device facing upwards and not being squeezed against each other.
3) It should be checked regularly when placed for a long time. Every three months, check the dirt and rust on the two passages, the sealing surface, and the protection status of the welding joint. After wiping the dirt and rust, repaint the anti-rust oil for protection.
4) In order to prevent the reverse flow of the medium, check valves should be installed on the equipment, devices and pipelines;
5) silent check valve is generally suitable for clean medium, not suitable for medium containing solid particles and high viscosity;
6) Generally, vertical silent check valves should be used on horizontal pipelines with a nominal diameter of 50mm;
The silent check valve should be stored in a dry and ventilated room to prevent moisture, rain and rust.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Video of dual plate wafer check valve: https://youtu.be/XqRRI7o-LFI

Difference between forged valve and cast valve

April 8, 2022

What is the difference between a forged valve and a cast valve? This article will explain to you how to distinguish between forged and cast valves.

PN40-DN100 cast steel WCB gate valve photo

forged valve:
Forged valves are forged and forged, and are generally used on high-grade pipelines with relatively small diameters, generally below DN50.
1. Forging: It is a processing method that uses a forging machine to apply pressure to a metal blank to cause plastic deformation to obtain a forging with certain mechanical properties, certain shape and size.
2. Forging materials are mainly carbon steel and alloy steel of various compositions, followed by aluminum, magnesium, titanium, copper, etc. and their alloys. The original state of the material is bar, ingot, metal powder and liquid metal. The ratio of the cross-sectional area of the metal before deformation to the die cross-sectional area after deformation is called the forging ratio. Correct selection of forging ratio has a lot to do with improving product quality and reducing costs.

Cast valve:
Casting valves are valves made by casting. Generally, the pressure levels of cast valves are relatively low (such as PN16, PN25, PN40, but there are also high-pressure ones, which can reach 1500Lb, 2500Lb), and most of the calibers are above DN50.
1. Casting: It is the process of smelting metal into a liquid that meets certain requirements and pouring it into a mold. After cooling, solidification, and cleaning, a casting (part or blank) with predetermined shape, size and performance is obtained. The basic technology of modern machinery manufacturing industry.

forged ball valve-3pcs-high PN

2. The cost of the blank produced by casting is low, and it is more economical for parts with complex shapes, especially with complex inner cavities; at the same time, it has wide adaptability and good comprehensive mechanical properties.
3. Materials (such as metal, wood, fuel, molding materials, etc.) and equipment (such as metallurgical furnaces, sand mixers, molding machines, core making machines, shakeout machines, shot blasting machines, cast iron plates, etc.) required for foundry production ) more, and will produce dust, harmful gas and noise and pollute the environment.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Video of center-lined butterfly valve: https://youtu.be/NuSZH_AJcwY
Video of resilient seated gate valve: https://youtu.be/AI-LT1dy2sU
Related news/knowledge:
cast steel gate valve vs stainless steel gate valve
The difference between carbon steel and cast steel
Valve material and valve standards-(1)

Posts

Driving device for Manual Wafer Butterfly Valve

Where can butterfly valves be used

Advantages and Disadvantages of Centerline Butterfly Valves

Installation and operation method of manual butterfly valve

Stem structure and Integral Seat of centerline wafer butterfly valve

Stem structure of centerline wafer butterfly valve

wafer type single plate swing check valve manufacturer

What are the advantages of gate valves-resilient & metal seated

Principle and Maintenance of Silence Check Valve

Difference between forged valve and cast valve

TH VALVE • PROFESSIONAL VALVE MANUFACTURER

GET IN TOUCH WITH US