butterfly valve Archives

Factors affect the sealing performance of butterfly valves

October 19, 2021

For the choice of butterfly valve, sealing is the most important attribute, because it directly affects the effect of butterfly valve throttling and is a direct manifestation of the quality of butterfly valve products. However, for most

wafer type butterfly valve, NBR seat (11)

working conditions, sealing does not mean that one drop is not allowed to leak. For the sealing performance of the butterfly valve, the accurate judgment standard should be: any sealing is allowed to have a small amount of leakage sometimes, if the leakage is not effective, it can be considered as sealed. The use experience of the valve shows that, in many cases, it is unnecessary to put high requirements on the sealing performance of the valve, because some working conditions completely allow a small amount of leakage of the medium, because this leakage is not enough to affect the use of the valve.
Of course, there are also more demanding working conditions in terms of sealing, usually for high pressure or corrosive media, and pipelines that transport flammable, explosive and toxic media. The leakage of the medium between the valve sealing surfaces may cause personal hazards, economic losses, and even In the event of an accident, etc., the tightness requirements should be reasonably put forward according to the danger level of the medium.
For example, for a hard-sealed butterfly valve, a certain amount of leakage is allowed when the sealing performance test is performed in the closed state in accordance with the technical standards for valve manufacturing. However, in order to ensure the high sealing performance of the hard-sealed butterfly valve, Tanghai Valve still carefully grinds the sealing surface, increasing the specific pressure on the sealing surface within the allowable specific pressure range of the sealing surface material, and improving the rigidity of the structure at the same time. At the same time, Tanghai Valve has stricter requirements on design, manufacturing and processing, such as:
(1) The quality of the valve body and bonnet, especially during forging or casting, should avoid defects and uneven composition such as folding, slag inclusion, pores, organization evacuation, and hidden cracks.
(2) The processing quality of the connecting parts of the valve stem and the valve body is improved, especially the roughness of the valve stem and the stuffing box, the straightness of the valve stem, the verticality of the stuffing box hole of the bonnet, and the processing accuracy are increased.
(3) The structure selection of the valve stuffing box. Since the seal at the valve stem is a dynamic seal, the packing is easy to wear during the rotation or sliding process of the valve stem. It is necessary to select a special low-leakage packing seal and packing seal combination, and strictly control the packing and packing. The gap between the valve stem, the gap between the packing and the stuffing box.
In summary, in addition to meeting the process conditions and standard specifications, the sealing performance of the control butterfly valve should also be fully considered for various operating conditions. In the engineering design, the sealing level of the butterfly valve should be selected to meet the principles of safety, reasonableness and economy.

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

Characteristics of the centerline wafer butterfly valve

October 14, 2021

The centerline wafer butterfly valve is one of the commonly used butterfly valves. It is named because of the structure of the stem axis, the center of the butterfly plate and the center of the body at the same position. The structure of the centerline butterfly valve is very simple, and the installation and maintenance are also very

Wafer type butterfly valve with worm gear

convenient. As a component that controls the on-off and flow rate of the pipeline system, the centerline clamp valve is widely used in pipeline systems in the fields of petroleum, chemical industry, hydropower station, municipal construction, water supply and drainage.
The sealing form of the centerline wafer butterfly valve is generally a soft seal, and the sealing material is rubber or polytetrafluoroethylene, so the centerline wafer butterfly valve is usually a soft sealing butterfly valve. Therefore, the advantages of this type of valve are that the seal can be replaced, the sealing performance is excellent and reliable, zero leakage can be achieved, and two-way sealing can be achieved. . However, due to the limitation of its own structural characteristics, the centerline wafer butterfly valve also has some shortcomings. Because the butterfly plate and valve seat of the valve are always in a state of squeezing and scratching, the resistance distance is large, and the wear on the butterfly plate and valve seat is very large, so In order to overcome the phenomenon of squeezing and scratching and ensure the sealing performance of the valve, the valve seat of the centerline butterfly valve adopts elastic materials such as rubber or polytetrafluoroethylene to ensure the sealing performance of the valve. However, materials such as banana and polytetrafluoroethylene are subject to temperature restrictions in use. Therefore, the disadvantage of the centerline butterfly valve is that it is not resistant to high temperatures.
The centerline wafer butterfly valve is not suitable for high temperature and high pressure working environment, has poor wear resistance and short service life. These shortcomings make the scope of application of the valve have certain limitations. In order to overcome this problem, there is now a triple eccentric metal hard seal butterfly valve, which is different from the centerline wafer butterfly valve. The stem axis of the triple eccentric butterfly valve deviates from the center of the butterfly plate and the center of the body at the same time, and the rotation axis of the valve seat and the axis of the valve body channel There is a certain angle. Compared with the centerline butterfly valve, the triple eccentric butterfly valve is more resistant to high temperature, and also has good sealing performance and longer service life.
The valve body and the valve seat are connected components, and the sealing surface layer of the valve seat is welded with temperature-resistant and corrosion-resistant alloy materials. The multi-layer soft laminated sealing ring is fixed on the valve plate. Compared with the traditional butterfly valve, this butterfly valve has high temperature resistance, light operation, no friction when opening and closing, and when closing, the torque of the transmission mechanism increases to compensate for the sealing, which improves the butterfly valve. The advantages of sealing performance and extended service life.

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

Comparison of pin butterfly valve and pinless butterfly valve

October 13, 2021

We often hear such statements as pinless butterfly valves and pinless butterfly valves in the purchase of butterfly valves. Because of technological reasons, pinless butterfly valves are usually more expensive than pinned butterfly valves. This makes many customers think whether pinless butterfly valves are more expensive than pinless butterfly valves. Is it better to have a pin butterfly valve? How does a pin butterfly valve compare with a pinless butterfly

Wafer butterfly valve-PN20-WCB-ANSI-150 (3)

valve? This article introduces Tanghai Valve for you.
From the appearance point of view of the pin butterfly valve and the pinless butterfly valve, the most essential difference is whether there is a tapered pin positioning on the valve plate. The connection method that uses a pin to penetrate the valve plate and the valve stem is a pin butterfly valve, and vice versa is a pinless butterfly valve. For pin butterfly valves and pinless butterfly valves, they have their own advantages and disadvantages. The specific situation is as follows:
Appearance comparison-the pinned butterfly valve has obvious pin head protrusions, which is not as smooth and beautiful as a pinless butterfly valve, but in fact it does not have a huge impact on the overall appearance.
Process comparison-the structural processing technology of the pin butterfly valve will be relatively simple, but if it needs to be repaired after long-term use, it will be more troublesome to disassemble the shaft and valve plate. Because the pin usually hit is that the pile pin is hard pressed up with a press, it is not easy to take out the valve stem. The pinless butterfly valve is relatively complicated in structure and technology because of the different ways of

wafer-type-butterfly-valve-with-handle-13

transmitting torque, but the later maintenance and disassembly are more convenient and convenient for repair.
Stability comparison——Because the pin butterfly valve is fixed with pins, the stability is definitely better than the pinless structure. The pinless structure affects the accuracy of the action due to the wear of the mating surface of the axle and the gate after long-term action. Therefore, the quality of pinless butterfly valves produced by manufacturers without mature processing technology and equipment is more worrying. This is also to remind customers and friends that if there is a demand for non-sold butterfly valves, you must choose a manufacturer with sound qualifications and mature production experience like Tanghai Valve. After all, Tanghai Valve has been in the valve manufacturing industry for 24 years, and it will be more professional in terms of quality, craftsmanship and management.
Sealing comparison-Finally, let’s take a look at the comparison of sealing effects. There is a saying that in actual use, the pin butterfly valve may see the medium from the pinned place to between the valve plate and the valve stem. The hidden danger brought by this is that the pin will be corroded and broken after a long time, causing the valve to fail to work, or the ejector rod leakage or the internal leakage of the pipeline. However, many manufacturers have begun to notice this problem. For example, Tanghai will choose to weld a layer of pins on the valve plate and shaft to prevent leakage from the pins.
In summary, compared with pin butterfly valves and pinless butterfly valves, objectively speaking, each design has its own characteristics and advantages, and one cannot simply say which one is better. As long as we choose the product that is most suitable for our cost budget and most suitable for our working conditions, it is a good product that suits us.

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

Introduction to the Features of Lever Wafer Butterfly Valve

October 9, 2021

Lever or Handle wafer butterfly valve is a kind of butterfly valve, usually with soft seal, which consists of a sealing surface made of rubber or fluoroplastic as a sealing material and a valve plate and stem made of carbon steel or

wafer-type-butterfly-valve-with-handle-13

stainless steel. Due to the limitation of the sealing surface material, the handle wafer butterfly valve is only suitable for water, gas, oil and other fluid media with a temperature of ≤80～120℃. The application fields include chemical industry, petroleum, electric power, textile, papermaking, construction water supply and drainage, etc. It is used for on-off control of normal temperature and pressure pipeline media on pipelines that transport various corrosive and non-corrosive fluid media in the engineering system, and can also be used for flow adjustment.
Handle wafer butterfly valves are generally only suitable for small-diameter valves, that is, valves with a diameter less than or equal to DN200mm. Because the small-diameter torque is relatively small, the opening and closing of the valve can be directly controlled by hand. The caliber is greater than 200mm, and according to the specific size of the caliber, it needs to be equipped with a turbine head, a pneumatic device or an electric device.
Because the handle wafer butterfly valve is a soft sealing butterfly valve, when the valve is installed and used, the valve must be opened at an angle, which is generally between 5°-10°. Do not allow the sealing surface rubber to be squeezed for a long time. state.
The main features of the handle wafer butterfly valve are:
1. The design structure is simple and unique, small in size, light in weight, and easy to operate.
2. Small-caliber operating torque is small, labor-saving and dexterous, opening and closing quickly.
3. It can be installed at any position of the pipeline, which is very convenient for installation and maintenance.
4. Handle wafer butterfly valves are usually soft-sealed, with reliable sealing performance, and can achieve two-way sealing with zero leakage.
5. The sealing surface material is easy to replace, resistant to aging, weak corrosion, and has a long service life.
Founded in 1994, Tanghai Valve is a professional valve manufacturer integrating design, development, production, sales, installation and service, and a high-quality valve manufacturer. The leading products include: wafer butterfly valves, flanged butterfly valves, hard-sealed butterfly valves, gate valves, butterfly check valves and other water series control valve products and related supporting pipeline accessories. The product sales range covers all parts of the country, and it has developed steadily in developing countries and regions such as Asia, Africa, and Latin America, and has successfully opened markets in developed countries and regions such as Europe and the United States. Products are widely used in water supply and drainage, electric power, petrochemical, metallurgical and other industries.

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

Correct installation of flanged butterfly valve can effectively prevent leakage

September 28, 2021

Butterfly valve has the advantages of good flow adjustment function and good closing and sealing characteristics, so it has become one of the fastest-growing valve varieties in the past ten years. It has simple and compact structure, light weight, convenient operation, reliable performance, complete functions, beautiful appearance, easy

Double flange butterfly valve (16)

maintenance, and is very popular with customers. In actual working conditions, if you want the flanged butterfly valve to achieve effective leakage prevention, the correct installation method is very important. Today, the editor of Tanghai Valve will share with you the installation precautions of the flange butterfly valve, as follows:
1. Before installation, you must carefully check whether the valve’s logo and certificate meet the requirements for use, such as Tanghai D342X flange rubber-sealed butterfly valve, to see whether the product brand, model, etc. are consistent with the valve required for the pipeline, and clean it after verification. Here is also the storage problem of flanged butterfly valves: the butterfly valves that have not been installed and used for the time being must be stored in a dry room; the butterfly valves that have been stored for a long time should be cleaned regularly, blown dry, and coated with anti-rust oil. The flange sealing surface should be protected by a blind plate.
2. Install according to the medium and its flow direction. For example, if you use water, you need to use ethylene-propylene rubber gaskets. When tightening the bolts, use the symmetrical or star-shaped torque method; if you use corrosive media, use PTFE gaskets. When tightening the bolts, use Torque on symmetrical or star-shaped method;
3. When installing the connecting bolts of the flange butterfly valve and the pipeline, do not tighten a single piece at one time, and should tighten it in diagonally opposite directions multiple times to prevent the uneven force from leaking at the flange connection.
4. When installing the butterfly valve, keep the butterfly plate in the closed position to prevent debris from entering the worn sealing surface. When the user is testing pressure, the pressure can be tested only after the two ends are installed with flange pairs.
5. When the valve is connected to the pipeline, flanges of appropriate specifications should be selected to ensure an effective sealing surface.
6. Before the electric flange butterfly valve is connected to the power supply for the first time, it needs to be manually adjusted to 1/3 of the closed position, and check whether the direction of the indicator plate is consistent with the opening direction of the valve.
7. When the flange butterfly valve is in use, if any malfunction is found, it should be stopped immediately.
Master the above correct installation method, flange butterfly valve will be more confidential and durable in application. If you are in need of purchasing high-quality flanged butterfly valves, Tanghai will be your best choice. The sealing surface of Tanghai flange butterfly valve has high processing precision, small opening friction and easy closing. Not only the self-sealing performance and the sealing performance are stable, but it also has the characteristics of self-locking that becomes tighter and tighter. It is suitable for gas, steam, air, water and other media. You are welcome to inquire.

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 of Triple Eccentric Metal seated Butterfly Valve

September 26, 2021

The triple eccentric butterfly valve belongs to the metal seated butterfly valve. The triple eccentricity is named because its stem axis deviates from the center of the disc and the center of the body at the same time, and there is a certain angle between the axis of rotation of the valve seat and the axis of the valve body channel. The triple-eccentric butterfly valve is corrosion-resistant, wear-resistant, and has a long service life. It is suitable for working conditions

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

where the medium temperature is ≤425℃. It is widely used in metallurgy, electric power, petrochemical, and water supply and drainage, municipal construction and other industrial pipelines for adjustment. Flow rate and use of off-load fluid. The body materials of the triple eccentric butterfly valve are cast iron, cast steel and stainless steel. This article will make an analysis and introduction to the advantages of the triple eccentric butterfly valve.

1. The metal-to-metal elastic hard seal structure is a structure in which an elastic metal J-ring is installed on the valve seat. The J-ring is pressed by a pressure plate and fixed with bolts. The two sides of the J-ring are respectively provided with sealing rings with good sealing performance, high temperature and high pressure resistance, and a certain margin. The position of the J-ring can be adjusted to make the valve After a period of use, it will not leak due to wear. The valve is suitable for medium and high temperature and medium and high pressure pipeline systems.

2. High wear-resistant self-lubricating composite bearings are used in the key parts of the relative movement of the shaft and the body to reduce the friction of the butterfly plate when it is opened or closed, and to ensure that there is no wear between the shaft and the body.

3. At the bottom of the lower shaft of the valve body, a high-hardness wear-resistant alloy spherical thrust pad and a high-hardness flat pad are used. During the movement of the butterfly plate, all downward gravity and friction forces are concentrated here. Due to the high hardness of the two thrust pads, the small contact area, long-term movement without abrasion, to ensure that the valve opens and closes easily, and never sinks.

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

4. The triple eccentric structure is a qualitative leap of the butterfly valve. Therefore, the valve greatly improves the service life and significantly improves the opening and closing torque. If you don’t understand the triple eccentric structure, you can click (https://www.tanghaivalve.com/triple-eccentric-butterfly-valve-th-btv-te/) to view.

5. The metal-to-metal multi-layer composite hard seal structure is a structure in which a multi-layer composite metal ring is installed on the valve plate. The multi-layer composite metal ring is made of stainless steel metal plates and flexible graphite sheets repeatedly laminated and pressed, which has high strength and rigidity. Flexible graphite still has good sealing performance under high temperature and high pressure. The combination of rigidity and flexibility of these two materials makes the valve suitable for most media, with a wide range of applications and long service life.

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

Introduction to the applicable occasions of butterfly valve

September 24, 2021

Butterfly valve is one of the most commonly used valves in piping systems. It has a wide range of applications. It can not only be used to cut off the flowing medium in the pipeline, but also can be used for flow adjustment. When the

Fluorine lined butterfly valve-PTFE-WAFER (10)

fluid in the pipeline passes through the butterfly valve, the pressure loss is about 3 times that of the gate valve, and the pressure loss is relatively large. Therefore, two factors should be considered when choosing a butterfly valve. One is the pressure loss experienced by the piping system, and the other is the pressure of the pipeline medium and the working temperature that the elastic valve seat material can withstand when the butterfly valve is closed.
The structural length of the butterfly valve is short, the overall height is also small, the operating torque is short, it can be opened and closed quickly, and fluid control can be performed well. The structural principle of the butterfly valve makes it most suitable for making large-diameter valves. When the butterfly valve is required to be used for flow control, in order to make it work more effectively, it is necessary to select the correct size and type of the butterfly valve.

What occasions are butterfly valves suitable for?

Double eccentric-wafer butterfly valve-D372F-150lbP-stainless steel (1)

1. It is required to be used for throttling and regulating control in the pipeline, and the valve structure is required to be short in length and fast in opening and closing. It is recommended to use a butterfly valve.
2. On pipelines that require two-position adjustment and necking, low noise is required, cavitation is generated, a small amount of leakage into the atmosphere, and the circulating medium is corrosive, a butterfly valve can be selected.
3. Under special working conditions where there are strict requirements for sealing, low temperature containing impurities, and easy to cause wear, it is recommended to use butterfly valves, and to use metal-sealed triple-eccentric or double-eccentric butterfly valves.
4. In petroleum, petrochemical, chemical, metallurgical, electric power and other fields, it is recommended to use metal hard-seal triple-eccentric butterfly valves. In many cases, they can replace gate valves and globe valves.
5. The center line butterfly valve is suitable for the environment with strict requirements on sealing performance and zero leakage. The center line butterfly valve is most suitable for fresh water, sewage, sea water, salt water, steam, natural gas, oil and oil at a working temperature of -10-150℃. Used in pipelines of various acid and alkali media.

triple offset butterfly valve-double flange- (5)

6. The double eccentric butterfly valve is very suitable for use in urban heating, gas, water and gas pipelines, as a device for intercepting or adjusting flow.
7. Eccentric soft sealing butterfly valves are widely used in gas pipelines and waterways in metallurgy, light industry, electric power and petrochemical systems. Used as a two-way opening, closing and adjustment of the ventilation and dust removal pipeline.

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

Introduction to the applicable occasions of butterfly valve

September 23, 2021

Butterfly valve is one of the most commonly used valves in piping systems. It has a wide range of applications. It can not only be used to cut off the flowing medium in the pipeline, but also can be used for flow adjustment. When the fluid in the pipeline passes through the butterfly valve, the pressure loss is about 3 times that of the gate valve, and the pressure loss is relatively large. Therefore, two factors should be considered when choosing a butterfly valve. One is the pressure loss experienced by the piping system, and the other is the pressure of the pipeline medium and the working temperature that the elastic valve seat material can withstand when the butterfly valve is closed.

U-type flange butterfly valve, ductile iron, DI, center line,

The structural length of the butterfly valve is short, the overall height is also small, the operating torque is short, it can be opened and closed quickly, and fluid control can be performed well. The structural principle of the butterfly valve makes it most suitable for making large-diameter valves. When the butterfly valve is required to be used for flow control, in order to make it work more effectively, it is necessary to select the correct size and type of the butterfly valve.

What occasions are butterfly valves suitable for?
1. It is required to be used for throttling and regulating control in the pipeline, and the valve structure is required to be short in length and fast in opening and closing. It is recommended to use a butterfly valve.
2. On pipelines that require two-position adjustment and necking, low noise is required, cavitation is generated, a small amount of leakage into the atmosphere, and the circulating medium is corrosive, a butterfly valve can be selected.
3. Under special working conditions where there are strict requirements for sealing, low temperature containing impurities, and easy to cause wear, it is recommended to use butterfly valves, and to use metal-sealed triple-eccentric or double-eccentric butterfly valves.
4. In the fields of petroleum, petrochemical, chemical, metallurgy, electric power, etc., it is recommended to use metal hard seal triple eccentric butterfly valve. In many cases, it can replace gate valve and stop valve.
5. The center line butterfly valve is suitable for the environment with strict requirements on sealing performance and zero leakage. The center line butterfly valve is most suitable for fresh water, sewage, sea water, salt water, steam, natural gas, oil and oil at a working temperature of -10-150℃. Used in pipelines of various acid and alkali media.
6. The double eccentric butterfly valve is very suitable for use in urban heating, gas, water and gas pipelines, as a device for intercepting or adjusting flow.
7. Eccentric soft sealing butterfly valves are widely used in gas pipelines and waterways in metallurgy, light industry, electric power and petrochemical systems. Used as a two-way opening, closing and adjustment of the ventilation and dust removal pipeline.

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 characteristics of the hard seal butterfly valve

September 22, 2021

Hard seal butterfly valve is a kind of butterfly valve with eccentric metal seal structure, and it is usually required to be installed horizontally in the pipeline. The sealing form of the metal hard seal butterfly valve is usually a metal-to-metal seal, and the sealing pair is composed of a metal hard material to a metal hard material. Hard-sealed butterfly valves can be driven by turbine manual, electric, pneumatic and so on.

triple offset butterfly valve-double flange- (5)

Nowadays, hard-sealed butterfly valves have been widely used in many fields such as petroleum, chemical industry, metallurgy, power generation, etc., to cut off or control the circulating medium in the pipeline system. At this stage, there is a relatively advanced hard-sealed butterfly valve, which is a triple-eccentric metal seated butterfly valve. Its body and seat are a conjoined component. On the sealing surface layer of the valve seat, a temperature-resistant and corrosion-resistant alloy material is surfacing welded. , And fix the multi-layer soft stacked sealing ring on the valve plate. The novel design allows the triple eccentric butterfly valve to overcome the shortcomings of poor sealing performance. The advantages of the triple eccentric butterfly valve are high temperature resistance, low friction when opening and closing, and when closed, the butterfly plate compensates for the seal along with the increase of the torque of the transmission mechanism, which greatly improves the sealing performance of the hard seal butterfly valve and prolongs the service life of the valve.

The advantages of the triple eccentric hard seal butterfly valve are:
1. The unique three-eccentric design enables frictionless transmission between the butterfly plate and the sealing surface of the valve body, reducing wear and extending the service life.
2. It can adapt well to low temperature, normal temperature and high temperature environment.
3. Pneumatic and electric devices can be configured according to the needs of users to meet the needs of remote control and program control.

The shortcomings of the triple eccentric hard seal butterfly valve are:
1. The butterfly plate of the hard sealing butterfly valve is fixed by multiple layers of soft and hard stacked sealing rings. When the butterfly plate is in the normally open state, the flowing medium will flush the sealing surface positively, which will affect the sealing performance of the valve over time.
2. Because the overall structure of the hard-sealed butterfly valve’s butterfly plate is too thick and the flow resistance is relatively large, the valve is not suitable for diameters below DN200.

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 characteristics of the soft sealing butterfly valve

September 18, 2021

Risilient seated /Soft sealing butterfly valve is one of the common butterfly valve types. It is a valve with simple structure and easy operation. It is mainly composed of valve body, valve stem, butterfly plate and sealing ring. The inside of the valve body is a cylindrical shape with a built-in butterfly plate. There are usually two ways to form the seal of a soft-seal butterfly valve. One is that the sealing pair is composed of a non-metallic soft material to a non-metallic soft material. Another is that the sealing pair is composed of a metal hard material to a non-metal soft

wafer type butterfly valve, EPDM seat (10)

material.
The most commonly used materials for the seat ring and seat of soft-sealed butterfly valves are EPDM, nitrile rubber, and polytetrafluoroethylene plastic. The soft-sealed butterfly valve with EPDM rubber seat material usually works in a working environment with a pressure less than 2.5Mpa and a temperature of -50~80℃. Applicable media include salts, acids, metal coating solutions, and water. , Wet chlorine, etc. The soft-sealed butterfly valve with nitrile rubber as the seat material usually works in a working environment with a pressure less than 2.5Mpa and a temperature of -10~90℃. The applicable media include water, oil, waste liquid, etc. The soft-sealed butterfly valve with polytetrafluoroethylene as the seat material can be used in an environment where the pressure is less than or equal to 1.6Mpa and the temperature is -196~200℃. The applicable media include heat resistance, cold resistance, general chemicals and solvents, and most of the liquid.
The advantage of the soft sealing butterfly valve is that it has good sealing performance and can achieve zero leakage. The disadvantage is that it is not resistant to high temperature and high pressure, and the sealing surface is easily eroded by the flowing medium, and the service life is short. The characteristics of the soft sealing butterfly valve are as follows:
1. The valve body is small and light, easy to install, disassemble and repair, and can be installed at any position in the pipeline.
2. The whole valve has a simple structure and is very compact, with small operating torque, and can be opened and closed by rotating 90 degrees.
3. It has good flow regulation performance.
4. The seal can be replaced, the sealing performance is good, and the two-way sealing can be achieved.
5. The butterfly plate can be sprayed with a coating layer, such as nylon rubber or polytetrafluoroethylene, according to the needs of users.
6. Flange connection and wafer connection can be designed according to requirements.
7. According to the requirements of the working conditions, the soft-sealed butterfly valve can be driven manually, electrically or pneumatically.

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

Posts

Factors affect the sealing performance of butterfly valves

Characteristics of the centerline wafer butterfly valve

Comparison of pin butterfly valve and pinless butterfly valve

Introduction to the Features of Lever Wafer Butterfly Valve

Correct installation of flanged butterfly valve can effectively prevent leakage

Advantages of Triple Eccentric Metal seated Butterfly Valve

Introduction to the applicable occasions of butterfly valve

Introduction to the applicable occasions of butterfly valve

What are the characteristics of the hard seal butterfly valve

What are the characteristics of the soft sealing butterfly valve

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