Butterfly Valve of Marine Valve

Product Introduction

Marine butterfly valve adopts the mounted structure, which reduces the connection bolts of the valve body itself under the condition of high pressure and large diameter, enhances the reliability of the valve and can overcome the influence of system weight on the normal work of the valve.

Scope of application

Marine butterfly valve is widely used in coal chemical industry, petrochemical industry, rubber, paper making, pharmaceutical and other pipelines as the medium of the shunt confluence or flow switching device.

 

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV, DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services.

 

Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.

We are committed to “Build a top valve enterprise; Be a reliable partner!”

Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

Dual Plate Swing Check Valve/Double-Door Check Valve

The Dual Plate check valve is used for pure pipeline and industrial, environmental protection, water treatment, high-rise building water supply and drainage pipeline, to prevent the reverse flow of the medium. The double-door check valve adopts clamping type, the butterfly plate is two semicircle, and the sealing surface can be body surfacing wear-resistant material or rubber lining, wide range of use, reliable sealing.

If you need more information, please click here: dual plate swing check valve, you can get more information here.

 

 

 

 

 

 

Check valve opening and closing parts by the medium flow and force to open or close, to prevent the medium backflow of the valve called check valve. Check valves belong to automatic valves, mainly used for medium one-way flow on the pipeline, only allow the medium to flow in one direction, in order to prevent accidents.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valveball 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.

PTFE Lined Butterfly Valve

PTFE butterfly valve is to adapt to some corrosive environment with strong acid, strong alkali, petroleum, chemical, food and other special areas of need, the use of PTFE made of the valve body, has a strong anti-corrosion effect. It can replace the stainless steel body under conventional conditions, with higher cost performance. The butterfly plate of the butterfly valve is installed in the diameter direction of the pipe. In the cylindrical channel of the butterfly valve body, the disc shaped butterfly plate rotates around the axis, the rotation Angle is 0°~90°, rotate to 90°, the valve brand is fully open.

Below photos are PTFE Lined Butterfly Valve of Tianjin Tanghai Valve, more information please click here: PTFE butterfly Valve.

 

 

 

 

 

 

PTFE (Teflon) butterfly valve can be equipped with AKR electric, BY pneumatic actuator, input control signal (4~20mADC or 1~5VDC) and single-phase power supply can control the operation, can realize intelligent type (regulating type) and switching type. With strong function, small size, light and pleasant, reliable performance, simple supporting, large circulation capacity, especially suitable for the medium is sticky, containing particles, fiber properties of the occasion.

At present, the PTFE butterfly valve, as a component used to realize the on-off and flow control of the pipeline system, has been widely used in petroleum, chemical industry, metallurgy, hydropower and many other fields. In the known butterfly valve technology, its sealing form is mostly sealed structure, sealing materials for rubber, PTFE, etc. Due to the limitation of structural characteristics, it is not suitable for high temperature resistance, high pressure resistance, corrosion resistance, wear resistance and other industries.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valveball 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

Concentric Type Butterfly Valve

Butterfly Valve according to the struction can be classified as: concentric type; eccentric type; triple eccentric.

Today we focus on introducing concentric type butterfly valve, what is concentric type butterfly valve according to structure? The rotary center of the valve disc is located on the center line of the valve body and through the center of the sealing surface.

This is a cross section of the butterfly valve with names on each part and a drawing of butterfly valve with gearbox. And you can also click here wafer butterfly valve to check more information.

The following figure explains the function of each component in detail:

 

 

 

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valveball 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.

Driving device for Manual Wafer Butterfly Valve

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)

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 valvegate valvecheck valveglobe valveknife gate valveball 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

Related news /knowledge:
Where can butterfly valves be used
Uses and characteristics of manual butterfly valve (1)
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What are the advantages of gate valves-resilient & metal seated

Where can butterfly valves be used

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)

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 valvegate valvecheck valveglobe valveknife gate valveball 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

Related news /knowledge:
electric hard seal butterfly valve vs electric soft seal butterfly valve
Installation and operation method of manual butterfly valve
Applicable occasions of butterfly valve
Ventilation butterfly valve installation instructions

Advantages and Disadvantages of Centerline Butterfly Valves

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)

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 valvegate valvecheck valveglobe valveknife gate valveball 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

Related news /knowledge:
electric hard seal butterfly valve vs electric soft seal butterfly valve
Installation and operation method of manual butterfly valve
Characteristics of the centerline wafer butterfly valve
Vulcanized vs soft seated/back-up butterfly valve

Installation and operation method of manual butterfly valve

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)

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 valvegate valvecheck valveglobe valveknife gate valveball 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

Related news/knowledge:
electric hard seal butterfly valve vs electric soft seal butterfly valve
Vulcanized vs soft seated/back-up butterfly valve
Ventilation butterfly valve installation instructions
The correct operation method of manual valve

Stem structure and Integral Seat of centerline wafer butterfly valve

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)

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 valvegate valvecheck valveglobe valveknife gate valveball 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

Related news/knowledge:

Stem structure of centerline wafer butterfly valve
Reasons and solutions for leakage of valve sealing surface
Characteristics of the centerline wafer butterfly valve
Centerline flange butterfly valve

Stem structure of centerline wafer butterfly valve

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)

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 valvegate valvecheck valveglobe valveknife gate valveball 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

Related news /knowledge:
Comparison of pin butterfly valve and pinless butterfly valve
Structural characteristics & features of flanged butterfly valves
Precautions for installation of pinless wafer butterfly valve
Structural Characteristics and application of Centerline Butterfly valves