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What are the taboos when installing valves

The valve is an important component in the fluid pipeline, and it is also a relatively fragile pipeline control device. Installing a valve is a technical task. It seems easy. In fact, there are many details to pay attention to. If there are some contraindications when installing the valve, it is serious. It will cause immeasurable consequences. This article will explain this problem to help you install valves safely and produce safely.

manual valve installation site-method

manual valve installation site-method

Taboos during valve installation
1. During winter construction, the valve shall be hydrostatically tested in a sub-zero temperature environment.
Possible consequences: due to the rapid freezing in the tube during the hydraulic test, the tube freezes.
The correct method: try to do a hydraulic test on the valve before the winter as soon as possible. After the pressure test, the water inside and outside the valve must be cleaned to prevent the valve from freezing and cracking in winter. If it is necessary to do a water pressure test in winter, it needs to be carried out indoors at a temperature above zero. Similarly, the water must be removed after the pressure test.

2. The sewage, rainwater, and condensate pipes for concealed installation are not subject to closed-water tests.
Possible consequences: Once there is a problem with the pipeline, it can not be found in time, and there will be water leakage, which will cause losses to the user.
The correct method: For concealed sewage, rainwater, condensate pipes, etc., closed water tests must be performed in strict accordance with the specifications to ensure that there is no leakage.

3. The flange of the butterfly valve can be replaced by the flange of the ordinary valve at will.
Possible consequences: Because the size of the flange of the butterfly valve is different from that of the ordinary valve, the disc of the butterfly valve is relatively large. If the inner diameter of the flange is too small, it will affect the opening and closing of the butterfly valve and cannot open normally , And eventually damage the valve. Measures: Correct method: Process and install the flange according to the actual size of the butterfly valve flange.

4. The valve installation method is wrong, for example, the installation direction is wrong, and the installation is not carried out in the direction indicated by the valve instruction.
Possible consequences: valve operation failure, difficult opening and closing, troublesome maintenance, leakage of valve body seal.
Correct method: When installing the valve, install it in strict accordance with the valve installation manual. After the installation is completed, check it against the manual.

5. The installed valves, specifications and models do not meet the design requirements.
Possible consequences: affect the normal use of the valve, or even damage the valve and cause losses.
The correct method: Before installing the valve, you must fully understand the working conditions and environment of the construction, and at the same time, you must be familiar with the application range of various valves, and select the valve model and specifications in strict accordance with the requirements of the working conditions.

6. Before installing the valve, the quality inspection of the valve was not carried out in accordance with the regulations.
Possible consequences: Failure to conduct quality inspection on valves, resulting in unqualified valves being installed on pipelines, increasing the possibility of pipeline leakage, and also increasing potential safety hazards in production.
Correct method: Before the valve is installed, the valve must be strictly inspected. The test should be 10% of the total number of valve products in each batch to ensure that the valve meets various national standards.

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

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Cleaning /Purge method of triple eccentric butterfly valve

As a new type of high-performance butterfly valve product, triple eccentric butterfly valve is widely used in heating, heating, gas supply, water supply pipeline and heating system of power station. After the triple eccentric butterfly valve is installed on the pipeline, it must be purged before work. After the butterfly valve and the pipeline are

triple offset butterfly valve-double flange- (5)

triple offset butterfly valve-double flange- (5)

installed, purging is required. The purging is to clean the pipeline and prevent the medium in the pipeline from affecting the normal operation of the valve. . What are the purge methods for the triple eccentric butterfly valve?

There are three common purging methods for triple eccentric butterfly valves: water flushing, air purging, and steam purging. Let’s introduce them one by one below.

Water flushing method:
1. Use clean water when flushing valves and pipes with water.
2. When flushing, use the maximum flow rate, and the flow rate of the water flow is not less than 1.5m/S.
3. The valve and the drainage branch of the pipeline must be flushed.
4. Water rinsing should be carried out continuously, until the color and transparency of the drain outlet are basically the same as the inlet water from the naked eye, it is qualified.
5. After the valves and pipelines have been flushed with water, if they are not put into production temporarily, the water inside should be completely drained to keep the valve body and pipeline dry.

Air purging method:
1. Air purging uses a large container in a large compressor to perform intermittent purging of valves and pipes. The purging pressure cannot exceed the design pressure of the vessel and pipeline.
2. When purging oil-free pipelines, the gas must not contain oil.
3. After air purging the pipeline, you can paste a white cloth or white painted wooden target board on the pipeline exhaust port where the valve is installed to check whether the pipeline is cleaned. After blowing for a few minutes, there is no rust on the white cloth. Other sundries such as dust are qualified.

Method of steam purging:
1. During steam purging, a temporary pipeline should be installed, which should be installed in accordance with the technical requirements of the steam pipeline.
2. The steam pipeline is used for purging the valves and pipelines with a large flow of steam, and the flow rate of the steam is not less than 30m/s.
3. Before steam purging, the pipes should be warmed up and the water in the valves and pipes should be drained. The pipes should be warmed up, drained in time, and the thermal displacement of the pipes should be checked.
4. The steam purging should be carried out in a cycle, and the sequence is heating-cooling-reheating.

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

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Problems Existing in the Use of Triple Eccentric Butterfly Valves

The triple eccentric metal seated butterfly valve is a high-quality valve category with high reliability and a wide range of applications. The triple eccentric butterfly valve is composed of main components such as valve body, butterfly

D673H-16C-stainless steel pneumatic triple eccentric butterfly valve

D673H-16C-stainless steel pneumatic triple eccentric butterfly valve

plate, valve stem, multi-layer metal sealing ring, shaft seal and drive mechanism. Its advantages are solid structure, good sealing performance, small torque, easy automatic control, etc. The triple eccentric butterfly valve is suitable for a variety of demanding working conditions, and has a wide range of applications in petroleum refining, natural gas extraction, chemical industry, power stations, metallurgy, and urban heating. However, things have two sides, and there are many problems in the use of the three-eccentric metal seated butterfly valve.
1. The butterfly plate of the triple eccentric butterfly valve is fixed with multiple layers of soft and hard stacked sealing rings. When the butterfly plate is in the open state, the circulating medium will directly wash the sealing surface. The soft sealing material in the metal sheet sandwich is in the long-term wash of the medium. It will directly affect the sealing performance of the valve.
2. The triple eccentric butterfly valve is not suitable for valves with a diameter smaller than DN200 because of its own structural constraints, the entire butterfly plate is very heavy and the flow resistance is very large.
3. The sealing between the butterfly plate sealing surface and the valve seat of the triple eccentric butterfly valve is to press the butterfly plate against the valve seat by the torque of the transmission device. When the medium in the pipeline is in a state of positive flow, the higher the pressure of the medium, the tighter the sealing and squeezing. But when the medium in the pipeline flows back, the pressure of the medium may cause seal leakage.
In order to solve the problems existing in the use of the triple eccentric butterfly valve, a high-performance triple eccentric two-way metal seated butterfly valve was developed. For the two-way sealing triple eccentric butterfly valve, the seat sealing ring is composed of multiple layers of stainless steel sheets on both sides of the soft T-shaped sealing ring. The sealing surface of the butterfly plate and the valve seat is an oblique cone structure, and then a high temperature and corrosion resistant alloy material is surfacing on the sealing surface of the oblique cone structure, and the spring fixed between the pressure plate of the adjusting ring and the adjusting bolt of the pressure plate are assembled together .
This special structure effectively compensates for the elastic deformation between the shaft sleeve of the triple eccentric butterfly valve and the valve body, and perfectly solves the problem that the triple eccentric butterfly valve is prone to leakage during the two-way interchangeable medium delivery process. The soft T-shaped sealing ring composed of multilayer stainless steel sheets on both sides not only has the advantages of a metal seated material, but also has the characteristics of a soft sealing material. Therefore, the three-eccentric butterfly valve with two-way sealing is suitable for both low temperature and high temperature conditions. Under the conditions, it can maintain excellent sealing performance.

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

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Selection and application of eccentric butterfly valve
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Factors Affecting the Operation and Use of resilient seated Butterfly Valves

Butterfly valves are classified according to the sealing material, which can be divided into resilient seated   butterfly valves and hard-sealed butterfly valves. There is a big difference in the scope of use between the two. The sealing pair of the resilient seated butterfly valve is composed of two parts. One side of the sealing pair is made of metal hard

U-type-flange-butterfly-valve-2

U-type-flange-butterfly-valve-2

material and the other side is non-metal soft material. This combination makes the resilient seated butterfly valve have good sealing performance and can achieve zero leakage. However, compared with hard-sealed butterfly valves, resilient seated butterfly valves are not suitable for high temperature environments.

The resilient seated butterfly valve is small in size, light in weight, and has good sealing performance. It is responsible for switching on and off and controlling fluid flow in the pipeline system. It has a very wide range of applications in petroleum, chemical, metallurgical, and municipal construction industries.

The connection method of resilient seated butterfly valve is flange type and wafer type. In the process of operating and using resilient seated butterfly valve, some situations are often encountered. Let’s take a look at the factors that affect the operation and use of resilient seated butterfly valve.

  1. In the valve market, rubber and PTFE are the most commonly used sealing materials for resilient seated butterfly valves. These sealing materials can maximize the sealing performance of resilient seatedbutterfly valves, regardless of whether it is a liquid or a gas medium. Zero leakage. However, because of the limitations of the structural characteristics of these sealing materials, the resilient seated  butterfly valve cannot be used in high temperature, high pressure and high-wear circulation pipelines. If any of the above conditions appears in the pipeline, the resilient seated   butterfly valve will malfunction and damage.

    Fluorine lined butterfly valve-PTFE-WAFER (10)

    Fluorine lined butterfly valve-PTFE-WAFER (10)

  2. The sealing ring of the resilient seated butterfly valve is fixed on the valve plate. When the butterfly plate of the butterfly valve is in the open position, the fluid medium in the pipeline will flush the sealing surface of the butterfly valve positively. Under the long-term erosion and corrosion of the fluid medium, the resilient seated material will wear out over time, which will affect the sealing performance of the resilient seated butterfly valve and cause leakage.

The factors that affect the operation of the resilient seated butterfly valve are the above two points. After the operator understands this information, he must pay attention to the use of the resilient seated butterfly valve, master the correct operation method of the resilient seated   butterfly valve, and regularly perform maintenance and repairs to maximize the resilient seated   butterfly valve Play a role and serve our industrial production.

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

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Applicable occasions and application conditions of butterfly valves

At present, the butterfly valve has become the most widely used valve in the application field. Many people are not very familiar with the applicable occasions of butterfly valves. This article will take you to understand the applicable occasions and application conditions of butterfly valves, so that you have a better understanding of butterfly valves.
When the valve plate of the butterfly valve is opened and closed, there is wiping property between the butterfly plate and the valve seat, so the butterfly valve can be used in the flowing medium pipeline with suspended solid particles, according to the strength of the seal. It can also be used in powder and granular flowing medium pipelines.

U-type-flange-butterfly-valve-2

U-type-flange-butterfly-valve-2

The structure length and overall height of the butterfly valve are not large, and the opening and closing speed is very fast. When the butterfly valve is fully opened, only the butterfly plate in the valve body is the only resistance to the flow of the medium, so the fluid resistance of the butterfly valve is also very small. Between 15° and 70°, sensitive flow control can be performed. Therefore, according to the structure principle of the butterfly valve, the butterfly valve is most suitable for making large-diameter valves.

Specifically, the application occasions of butterfly valves are as follows:
1. In the pipeline that requires throttling, adjustment and control of flow;
2. In the working environment of mud medium and medium containing solid particles;
3. In occasions requiring short valve structure length;
4. In occasions requiring fast opening and closing speed;
5. In occasions where the pressure difference is small.

The butterfly valve can also be used under the following conditions:
1. In the case of two-position adjustment, narrowing passage, low noise, cavitation and vaporization, a small amount of leakage to the atmosphere, and abrasive media, butterfly valves can be used.
2. Under special working conditions, throttling adjustment or strict sealing requirements, or severe abrasion, low temperature and other working conditions require the use of three-eccentric or double-eccentric special butterfly valves with metal sealing belts.

The above is an introduction to the applicable occasions and application conditions of the butterfly valve. I hope to provide you with help in the use of the butterfly valve. Tanghai Valve is a high-quality butterfly valve manufacturer. If you have a need for butterfly valves, look for the brand of Tanghai Valve.

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

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Installation and Maintenance of Butterfly Valve

The butterfly valve has become one of the most widely used valves. Although it is only a small part on the fluid pipeline, it has a very large effect. The installation and maintenance of butterfly valves is a science. The correct installation of butterfly valves is the first step to ensure the normal operation of the pipeline, and subsequent maintenance has a positive effect on prolonging the service life of butterfly valves and reducing production costs. This article will talk about the installation and maintenance of butterfly valves for you.

lug type butterfly valve, ductile iron, center lined,

lug type butterfly valve, ductile iron, center lined,

The working principle of butterfly valve
The working principle of the butterfly valve is that the valve stem drives the rotation of the butterfly plate to complete the opening and closing, and the rotation angle is 90°; changing the deflection angle of the butterfly plate can control the flow of the medium. Common butterfly valves include wafer butterfly valves and flange butterfly valves. Wafer type butterfly valve uses double-head bolts to connect the valve between two pipeline flanges. Flange type butterfly valve has flanges on the valve, and bolts are used to connect the flanges at both ends of the valve to the pipeline flanges. Butterfly valve allows fluid speed: liquid ≤ 4.5 m/s, gas ≤ 20 m/s.

Installation direction and position of butterfly valve

ductile iron, DI, butterfly valve, manufacturer, center line, TH valve

ductile iron, DI, butterfly valve, manufacturer, center line, TH valve

Butterfly valves generally have no direction requirements. If required, it should be determined according to the rotation angle of the butterfly valve and the working principle of the pneumatic actuator. The best position of the valve installed on the horizontal pipeline is vertical installation, and vertical downward is not allowed. The valve installation position must be easy to operate; timely installation is temporarily difficult, and the operator must also consider the long-term work of the operator. It is best to keep the valve hand wheel flush with the chest, generally 1.2 meters away from the operating floor, so that it is easier to open and close the valve. The handwheel of the floor valve should be upward, not tilted. For valves that lean against the wall against the equipment, leave room for the operator to stand on. It is necessary to avoid operating from the sky, especially acid-base, toxic media, etc., otherwise it is very unsafe.

Maintenance work of butterfly valve
When maintaining the butterfly valve, pay attention to whether there is water in the pneumatic actuator mechanism. In the wet season, the accumulation of water in the air compressor tank makes the transmission mechanism or the transmission shaft sleeve rust, and the accumulation of water in the air compressor tank in the cold winter weather enters the pneumatic actuator mechanism and freezes, causing aerodynamics. When the actuator is operated, the torque is too large, which damages the transmission components and cannot be operated manually; if the actuator is operated forcibly, the internal parts of the actuator will also be damaged. During maintenance, the discharge valve in the air compressor tank should be opened from time to time and the internal water should be taken out. For butterfly valves with hand wheels, open the turbine box cover to check whether the lubricating oil is normal within 6 months of operation, and keep a proper amount of lubricating oil.

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

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resilient seated butterfly valve vs metal seated butterfly valve

Butterfly valve, also called flap valve, has a wide range of uses. It is generally installed on pipelines that transport various corrosive and non-corrosive fluid media in gas, natural gas, liquefied petroleum gas, cold and hot air, chemical smelting and other engineering systems for adjustment. And cut off the flow of the medium. There are many types of butterfly valves, and different types of butterfly valves have different uses. Butterfly valves are classified according to the sealing form and can be divided into soft-sealed /resilient seated butterfly valves and hard-sealed /metal seated butterfly valves. Although there is only one word difference between the two types of butterfly valves, they are very different in terms of structural materials and application fields. This article will analyze the difference between a resilient seated butterfly valve and a metal seated butterfly valve.

wafer type butterfly valve, EPDM seat (10)

wafer type butterfly valve, EPDM seat (10)

The main difference between resilient seated butterfly valve and metal seated butterfly valve lies in the sealing surface:

The two sides of the sealing pair of the resilient seated butterfly valve are made of metal materials on one side, and the other side is made of elastic non-metallic materials, generally rubber or tetrafluoroplastics. The combination of this sealing material makes the resilient seated butterfly valve have good sealing performance, but it is not resistant to high temperature, easy to wear, and has a short service life.

Both sides of the sealing pair of the metal seated butterfly valve are made of metal materials. The metal-to-metal seal makes the sealing performance of the metal seated butterfly valve normal, but it is resistant to high temperature, pressure and abrasion, and has a long service life.

The seat of the soft sealing butterfly valve is made of rubber or tetrafluoroplastic. It has excellent sealing performance and can achieve zero leakage, but it has a relatively short service life and is not resistant to high temperatures. It is also not suitable for some highly corrosive media pipelines. The sealing seat of the hard-sealed butterfly valve is made of metal material, and the sealing performance is

D673H-16C-stainless steel pneumatic triple eccentric butterfly valve

D673H-16C-stainless steel pneumatic triple eccentric butterfly valve

relatively poor, but it is wear-resistant and has strong pressure resistance. It is suitable for strong corrosive medium pipelines.

In addition to the difference in the sealing surface, the difference between the resilient seated butterfly valve and the metal seated butterfly valve is as follows:

  1. Resilient seatedbutterfly valves are mostly center-line type. Metal seatedbutterfly valves are mostly single eccentric, double eccentric and triple eccentric.
  2. The Resilient seatedbutterfly valve is suitable for normal temperature environment. metal seatedbutterfly valves are well adapted to low temperature, normal temperature and high temperature environments.
  3. The Resilient seatedbutterfly valve is suitable for low pressure and normal pressure environment. metal seated butterfly valveis not only suitable for low pressure and normal pressure, but also suitable for medium and high pressure working environment.
  4. As mentioned above, the sealing performance of the Resilient seatedbutterfly valve is better than that of the metal seatedbutterfly valve, but now in order to adapt the hard sealing butterfly valve to more working conditions, it has a special process
  5. The Resilient seatedbutterfly valve is suitable for the two-way opening and closing of the ventilation and dust removal pipeline and the adjustment of water treatment, light industry, petroleum, chemical and other industries. metal seatedbutterfly valves are mostly used in heating, gas, gas, oil, acid and alkali environments.

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

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Ways to Extend the Service Life of Valves

In industrial production, we always want to reduce costs, increase production capacity, and maximize profits. In addition to vigorously developing scientific and technological productivity, in daily work, paying attention to some small details, avoiding waste, can also reduce costs. Valves are disposable items and have their own service life. Once this period has passed, they must be replaced with new ones. Frequent replacement of valves will increase our production costs. Therefore, extending the service life of the valve can also maximize our production benefits. This article will start with the selection of the valve and tell us how to maximize the service life of the valve during the process of valve maintenance.

marine valve; butterfly valve; check valve; gate valve; manufacturer in China

marine valve; butterfly valve; check valve; gate valve; manufacturer in China

Valve selection
Getting the best performance level of the valve is the first step in ensuring the life of the valve, so we have to make sure that the right valve is selected and used in the right place. In many cases, the main reason for valve leakage and failure is the wrong valve design or the wrong material of construction. Therefore, when selecting a valve, you must be clear about the parameters of the pipelined medium, use temperature, pressure, etc., and select the correct and appropriate valve according to the parameters.

Valve installation
After purchasing a suitable valve, pay special attention to the installation. On-site technicians may cause further damage to the valve when removing the valve end cover. When the end cover is removed, dust and foreign matter will be deposited in the valve, which may cause Damage to the ball and valve seat, and cause leakage once installed. So do not open the end cap without special reason.
Incorrect hoisting of pneumatic valves or electric valves will damage the actuators and valves. When transporting the valve on site, there is a lifting ring on the valve. Do not lift the valve or actuator through the valve stem. Therefore, during the installation phase, the most important step is to purge the pipeline before it is pressurized.

Valve maintenance
After the valve is installed, frequent maintenance is required to prevent the valve and drive equipment from malfunctioning. Every month, the valve in operation should be moisturized to optimize the performance of the valve.

Finally, there are some caveats:
1. Make sure that the start of the valve and the material list of valve control accessories conform to our specification sheet.
2. The valve packaging must be inspected to ensure that the exterior of the valve and components are intact during the transportation process, and all grease fittings are present.
3. Ensure that the valve process connection is covered to prevent dust and debris from entering the body cavity.
4. Pay attention to the valve manufacturer’s instructions for lifting and transporting the valve.
Tanghai Valve, a high-quality valve manufacturer, has better quality and longer service life. Escort your production work.

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

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Working principle and characteristics of triple eccentric butterfly valve

Triple eccentric butterfly valve, also named triple offset butterfly valve.

Nowadays, butterfly valves have been used in many industries. In the beginning, the butterfly valve was only used for the interception and communication of water media. The triple eccentric design enhances the function of the butterfly valve and has become one of the valves with excellent performance in industrial industrial pipeline equipment. The triple eccentric butterfly valve, as the name implies, is that three independent offsets are designed as valves. In reality, many people do not know which one is a triple-eccentric butterfly valve because of insufficient cognition. In this article, let’s talk about the working principle and characteristics of the triple-eccentric butterfly valve.

triple offset butterfly valve-double flange- (5)

triple offset butterfly valve-double flange- (5)

The working principle of the triple eccentric butterfly valve is that the valve body of the butterfly valve has a horizontal valve port connected to the pipeline in structure, and the valve port has a valve plate. The shaft is perpendicular to the valve port and penetrates the valve body and the valve plate. The edge of the valve plate is provided with an outer spherical surface, and the valve port is provided with a sealing surface that can be matched with the outer spherical surface. When the sealing surface and the outer spherical surface are matched and sealed, there is an eccentric distance a between the sealing line and the axis of the shaft, which is in the transverse center of the valve plate. The line is the eccentricity b between the center line of the valve port and the center line of the shaft, and there is an angle β between the connection line of the outer spherical surface and the center line of the valve port. This is the principle of the triple eccentric butterfly valve.
The triple eccentric butterfly valve cleverly puts the triple eccentricity on the valve plate, and adopts a partial outer spherical structure on the outer edge of the valve plate. This structure needs to be completed on a CNC machine with a self-designed simple fixture. The outer eccentric spherical surface is polished to reach a roughness of Ra0.4, the spherical surface is chrome-plated or made of Stellite alloy, and the hardness reaches HRC45-60.
Put the eccentric angle on the valve plate, and press the valve seat on the valve body with a pressing ring, which solves the difficulties encountered in the processing of ordinary triple eccentric butterfly valves. The valve body, valve plate and valve seat cannot be exchanged for pairing. Repair after damage A series of problems such as high cost, all parts are modularized, warehouse management is simple, processing is simple, maintenance is convenient, and the cost of spare parts is reduced.
The butterfly valve is suitable for making large-diameter valves. It can be widely used in the cutting of petroleum transportation pipelines, metallurgical steel plants, gas main pipeline adjustment and cutting, chemical smelting equipment medium adjustment and cutting, water treatment equipment inlet and outlet adjustment and shutdown, and cooling water in thermal power stations. System, natural gas, lye, sea water, acid and other industries.

The characteristics of the triple eccentric butterfly valve are as follows:
1. Simple structure, light weight, composed of only a few parts. easy to use.
2. After the valve plate is fully opened, the thickness of the butterfly plate is the only resistance for the medium to pass through the valve body. The pressure is small and the flow can be better controlled.
3. When the valve plate is closed, the specific pressure between the outer spherical surface of the valve plate and the sealing surface of the valve seat is generated by the driving torque applied to the shaft. Coupled with the elastic compensation of the M-type elastic valve seat, the sealing performance of the valve can be enhanced, and the service life is greatly improved.
Understand the working principle and characteristics of triple eccentric butterfly valve, then where can I buy high-quality triple eccentric butterfly valve products? of course, Tanghai valve.

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

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electric butterfly valve code naming method

Electric butterfly valve model preparation method, electric butterfly valve code naming method, only suitable in China.
With the increase in demand for valves in my country’s industrial manufacturing industry, electric butterfly valves have become a more prominent one among many valves. However, due to the wide variety of electric butterfly valves, and the difference in control modes and medium pressure and temperature, users often choose electric Uncertainty about butterfly valve models! In order to avoid such a situation, our company specially provides the electric butterfly valve model preparation instructions for your reference and understanding!

lug type butterfly valve, ductile iron, center lined,

lug type butterfly valve, ductile iron, center lined,

The electric butterfly valve model preparation instructions include the addition of additional conditions for the butterfly valve, the difference in connection methods, the upgrade of the transmission mode, the change of the structure, the level of valve pressure, and the requirements for temperature, pressure, corrosion and material. Hope It is helpful to everyone in the selection!
Model representation method of electric butterfly valve:
Additional codes for electric butterfly valves: BD thermal insulation butterfly valve, SD telescopic butterfly valve, TLD desulfurization butterfly valve, DH check butterfly valve, DKS fast butterfly valve, FDBD square louver butterfly valve;
The code of the butterfly valve: D represents the butterfly valve;
Transmission form code: manual (omitted), 3 means turbine drive, 6 means pneumatic drive, 7 means hydraulic, 9 means electric;
Connection code: 4 flange type, 6 welding, 7 pair clip type;
Code of structural form: 1 means centerline type, 2 means double eccentricity, 3 means triple eccentricity, 4 means variable eccentricity, 5 means single eccentricity;
Sealing material code: H stainless steel, X rubber, F polytetrafluoroethylene, FX composite rubber, M Monel alloy, Y cemented carbide, W valve body directly processed;
Pressure grade code: 10=PN1.0Mpa, 16=PN1.6, 25=PN2.5, 40=PN4.0, PN is the code of domestic pressure, MPA is the unit of pressure, one kilogram is equal to 0.1Mpa; Class150LB=1.6 mpa, 300LB=2.5-4.0mpa, Class is the American standard code, LB is the American standard pound unit.
Shell material code: C cast steel, P stainless steel 304, R stainless steel 316, AL special alloy steel, Z cast iron, Q ductile iron, N nylon. To
The above are common codes related to butterfly valves. For products that need to be customized due to special working conditions, they can be selected according to the design plan.
Electric butterfly valve model preparation instructions: D943H-16C Stainless steel electric flange hard-sealed butterfly valve

D943H-16C-metal seated stainless steel electric triple offset butterfly valve

D943H-16C-metal seated stainless steel electric triple offset butterfly valve

D: Represents butterfly valve;
9: Indicates that the transmission mode is electric;
4: The connection method is flange connection;
3: The structure is triple eccentric;
H: The sealing material is stainless steel;
16: Indicates that the nominal pressure is 1.6MPa;
P: Indicates that the valve body is made of stainless steel.
Related valve model: Pneumatic butterfly valve model Electric ball valve model Pneumatic ball valve model

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

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