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Which valves are used for wastewater and sewage treatment

January 20, 2022

Which valves are used for wastewater and sewage treatment? The continuous increase of water pollution in my country has made the sewage treatment and regeneration industry receive unprecedented attention. In the sewage treatment pipeline system, the valve plays a very important role.

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

Definition of sewage treatment
Sewage treatment: The process of purifying sewage in order to make it meet the water quality requirements for discharge into a body of water or for reuse. Sewage treatment is widely used in construction, agriculture, transportation, energy, petrochemical, environmental protection, urban landscape, medical treatment, catering and other fields, and is increasingly entering the daily life of ordinary people.

Sewage treatment classification
According to the classification of sewage sources, sewage treatment is generally divided into production sewage treatment and domestic sewage treatment. Production sewage includes industrial sewage, agricultural sewage and medical sewage, etc., while domestic sewage is sewage generated in daily life, which refers to the complex mixture of various forms of inorganic and organic substances, including: ① floating and suspended solid particles; ② glue shape and gel-like diffusion; ③ pure solution.
According to the quality of water pollution, there are two types of water pollution: one is natural pollution; the other is man-made pollution. At present, man-made pollution is the most harmful to water bodies. Water pollution can be divided into three categories: chemical pollution, physical pollution and biological pollution according to the different pollution impurities. The main pollutants are: (1) industrial wastewater discharged without treatment; (2) domestic sewage discharged without treatment; (3) farmland sewage with extensive use of chemical fertilizers, pesticides, and herbicides; (4) industrial waste and domestic garbage piled up by the river ; ⑸ soil erosion; ⑹ mine sewage.

Sewage treatment valve
Modern sewage treatment technology can be divided into primary, secondary and tertiary treatment according to the degree of treatment. Generally, the degree of sewage treatment is determined according to the water quality and the destination of the treated water. The valves used at each level are also different.
primary treatment
It mainly removes suspended solid pollutants in sewage, and most of the physical treatment methods can only complete the requirements of primary treatment. After primary treatment of sewage, BOD can generally be removed by about 30%, which does not meet the discharge standard. The primary treatment belongs to the preprocessing of the secondary treatment. Valves and their pipeline accessories are used: knife gate valve, triple eccentric butterfly valve, filter, etc.
secondary processing
It mainly removes colloidal and dissolved organic pollutants (BOD, COD substances) in the sewage, and the removal rate can reach more than 90%, so that the organic pollutants can meet the discharge standard, and the suspended solids removal rate can reach 95%, and the effluent effect is good. The valves used are soft-sealed butterfly valves, gate valves, ball valves, check valves, etc.
tertiary treatment
Further treatment of refractory organic matter, nitrogen and phosphorus and other soluble inorganic matter that can lead to eutrophication of water bodies. The main methods are biological denitrification and phosphorus removal, coagulation sedimentation, sand filtration, activated carbon adsorption, ion exchange and electrodialysis. The valves used are wafer butterfly valve, gate valve, ball valve, check valve, rubber soft joint, etc.

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

Video of center-lined butterfly valve: https://youtu.be/NuSZH_AJcwY
Video of triple eccentric butterfly valve: https://youtu.be/AkRwg2X1Wh0
Video of dual plate wafer check valve: https://youtu.be/XqRRI7o-LFI
Video of knife gate valve: https://youtu.be/vFSbTF_FGXM
Video of resilient seated gate valve: https://youtu.be/AI-LT1dy2sU

Precautions for the application of fluorine-lined valves

January 19, 2022

Appropriate selection and application of fluorine-lined anti-corrosion valves is a matter of concern to everyone in engineering. Tanghai Valve puts forward the following views based on years of field application experience for your reference. We are specialised in the production of fluorine lined butterfly valves.

lug butterfly valve-lined-PTFE-DI body (1)

The price of fluorine-lined butterfly valves is much lower than that of corrosion-resistant stainless steel valves and Hastelloy valves. Some metal valves with strong corrosive media cannot be used, but only plastic-lined valves can be used well. However, the plastic-lined valve must be suitable for application. It is hoped that several technical conditions such as application pressure and application temperature should be used. Take our company’s products as an example to illustrate the following:
(1) The temperature of the medium used in the fluorine-lined valve: Usually, the fluorine plastic used in the fluorine-lined valve is F46 (FEP), and the temperature of the medium used cannot exceed 150 °C (the medium temperature can reach 150 °C in a short time, and the temperature of the long-term use It should be around 120℃), otherwise, the F46 lining of various parts of the valve is easy to soften and deform, resulting in the valve not closing and the leakage is large.
If the temperature of the medium used by the user is below 180 °C for a short time and below 150 °C for a long time, another fluoroplastic, PFA, can be used, but the price of fluoroplastic lined with PFA is more expensive, so it should be used in advance when matching. Inquiry.
(2) Do not have negative pressure. Fluoroplastic-lined valves should avoid negative pressure in the pipelines used. If there is negative pressure, it is easy to cause the fluoroplastic-lined layer of the valve cavity to be sucked out (bulged) and shelled, resulting in failure of the valve to open and close.
(3) The pressure and differential pressure should be controlled within the allowable range. Especially the fluorine-plastic-lined regulating valve and globe valve sealed by bellows. Because the bellows is made of tetrafluoro material, the pressure is high and the pressure difference is high, which can easily lead to the rupture of the bellows.
Bellows-sealed fluoroplastic-lined regulating valve can be changed to PTFE packing seal if the operating condition pressure and differential pressure are high.
(4) The medium conditions used in the fluoroplastic valve should not have hard particles, crystallization, impurities, etc., so as to prevent the valve from breaking the valve core, the fluoroplastic layer of the valve seat or the tetrafluoro bellows during the opening and closing operation. For the medium with hard particles, crystals and impurities, when selecting, the valve core and valve seat can be changed to Hastelloy, but additional inquiry is required.

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

Video of PTFE butterfly valve:

Introduction to Common Butterfly Valve Materials

January 14, 2022

This article makes an introduction to the commonly used butterfly valve materials. For butterfly valves, you should already have a certain understanding. There are many types of butterfly valves. According to the different connection forms, they can be divided into wafer butterfly valves and flanged butterfly valves; according to different sealing surface materials, they can be divided into soft sealing butterfly valves and metal hard sealing. Butterfly valve;

Types of wafer butterfly valves

according to the different driving methods, it can be divided into handle butterfly valve, turbine butterfly valve, pneumatic butterfly valve, electric butterfly valve and so on. So what are the commonly used butterfly valve materials?
Commonly used butterfly valve materials are mainly cast iron, cast steel, stainless steel three categories. Each material can be further subdivided. Below we will give an introduction to these three types of butterfly valve materials.

Category 1: Cast Iron
Cast iron is subdivided into four categories: gray cast iron, malleable cast iron, ductile iron, and nickel cast iron. This article mainly introduces the two main cast iron materials made by Tanghai valve: gray cast iron, ductile iron and stainless steel.

lug butterfly valve-lined-PTFE-DI body (1)

Gray cast iron is cast iron with flake graphite, because the fracture is dark gray when broken, so it is called gray cast iron. Gray cast iron is the most widely used cast iron, and its output accounts for more than 80% of the total output of cast iron. The casting performance, cutting performance and wear resistance of gray cast iron are very good. Its disadvantage is that its strength, plasticity and toughness are lower than other cast irons.
Grey cast iron is used as the material of butterfly valve, which is usually suitable for weak acid and weak alkali media such as water and air, but not suitable for pipelines with perhydrochloric acid and nitric acid media.
Ductile iron is a high-strength cast iron material with very high strength, toughness and wear resistance, and its comprehensive performance is close to that of steel. At present, the application range of ductile iron is second only to gray cast iron. We often say “replace steel with iron”, which refers to ductile iron.

U type flange butterfly valve (4)

Ductile iron is used as the material of butterfly valve, which has certain corrosion resistance and performance is much higher than that of butterfly valve made of gray iron. The applicable medium includes steam, general gas and oil.

The second category: cast steel
Cast steel is a cast iron alloy, which is a general term for iron-based alloys used to produce castings that do not undergo eutectic transformation during solidification. The advantages of cast steel are greater design flexibility and variability, increased overall structural strength and a wide range of weight variations. Using cast steel as the butterfly valve material, the performance is better than that of cast iron but not as good as stainless steel. Butterfly valve made of cast steel is suitable for steam, non-corrosive gas, oil, etc.

The third category: stainless steel
Stainless steel refers to steel that is resistant to weak corrosive media such as air, steam, and water, and chemically corrosive media such as acid, alkali, and salt, also known as stainless acid-resistant steel. Generally, the butterfly valve made of stainless steel has the best performance and can be used in more severe working conditions. It is used in some ultra-high temperature, ultra-low temperature and strong acid-base corrosive medium pipelines. Wear-resistant and long-lasting.

The above is the introduction of commonly used butterfly valve materials. Generally speaking, the price of stainless steel butterfly valve is the highest, and gray cast iron is the cheapest. If you want to know more about butterfly valve, you are welcome to visit Tanghai Valve”

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

Video of center-lined butterfly valve:

Structure diagram of double eccentric butterfly valve

January 11, 2022

Double eccentric butterfly valves are often referred to as high performance butterfly valves. On the basis of the single eccentric butterfly valve, the most widely used double eccentric butterfly valve is further improved and formed.
Structural features of double eccentric butterfly valve: The center of rotation of the valve plate (ie the center of the valve shaft) forms a dimension α offset with the valve plate sealing section, and a dimension b offset with the centerline of the valve body.

double eccentric butterfly valve structure diagram

Sealing principle of double eccentric butterfly valve: On the basis of the single eccentric sealing butterfly valve, the center of rotation of the valve plate (ie the center of the valve shaft) is offset by a dimension b with the center line of the valve body. When the double eccentric sealing butterfly valve is in a fully open state, The valve plate sealing surface will be completely separated from the valve seat sealing surface, and a gap y larger than the X gap in the single eccentric sealing butterfly valve is formed between the valve plate sealing surface and the valve seat sealing surface, thereby reducing the opening and closing of the valve plate. Mechanical wear and abrasion between the two sealing surfaces of the butterfly valve seal pair.

high performance-double eccentric-butterlfy valve-wafer-lug-flanged (6)

In the usual design, when the valve plate is rotated from 0° to 8° to 12°, the sealing surface of the valve plate can be completely separated from the sealing surface of the valve seat, so that during the opening and closing process of the butterfly valve, the sealing surface between the valve plate and the valve seat is separated. Compared with mechanical wear, the extrusion angle stroke is shorter, so that the mechanical wear and extrusion deformation are further reduced, and the sealing performance of the butterfly valve is further improved.

The main reasons for the failure of the sealing performance of the double eccentric butterfly valve sealing pair
① During the opening and closing process of the butterfly valve, when the valve plate rotates and squeezes the elastic soft valve seat, the valve plate and the valve seat are mechanically worn and scratched;
②After the valve plate squeezes the elastic valve seat, the elastic valve seat or the elastic layer of the valve plate will produce permanent plastic deformation, cold flow, elastic failure, etc.;
③The material of the elastic valve seat or the elastic layer of the valve plate is aging and failing, etc.;
④ Medium cavitation and erosion of the sealing surface.

Features of double eccentric butterfly valve
①The structure is more complicated than the single eccentric sealing butterfly valve, and the cost is slightly higher;
②The sealing performance is better than that of the single eccentric sealing butterfly valve;
③The service life is longer than that of the single eccentric sealing butterfly valve, and the operating pressure is also higher.
Difference: Double eccentric butterfly valve can use metal seat, which improves the application of butterfly valve in high temperature field. However, because its sealing principle is a positional sealing structure, that is, the sealing surface of the disc and the valve seat is in line contact, and the elastic deformation caused by the disc extrusion of the valve seat produces a sealing effect, so it has high requirements for the closing position (especially metal Valve seat), low pressure bearing capacity, which is why traditionally people think that butterfly valves are not resistant to high pressure and have large leakage.

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

Video of double eccentric butterfly valve:

The role and application of gate valve

January 7, 2022

This article introduces you to the function of gate valve, and then understands the purpose of gate valve. The gate valve is a very important control component on the pipeline that transports the fluid medium. The structure of the gate valve is composed of a valve body, a valve cover, a valve stem, a gate plate, a sealing ring, and a driving device. The driving device is usually a hand wheel, and it can also be equipped with a pneumatic or electric actuator.

DIN-F4-BB-NRS-soft seated-wedge gate valve-DN100-PN16-copper holding ring-handwheel (3)

The gate of the gate valve is a disc shape, and the valve stem is driven to realize the opening and closing of the valve. The movement direction of the valve stem and the gate is perpendicular to the valve body passage and the direction of fluid flow in the pipeline. The gate valve has only two states, fully open and fully closed, so it can only be used to cut off the flow of the medium in the pipeline, and cannot adjust the flow rate. In addition, when the gate valve is opened and closed, the stroke distance of the gate is long. Although the opening and closing is labor-saving, it takes time. Therefore, the function of the gate valve is very suitable for use in pipelines that do not need to be opened and closed frequently, and used as a cut off or connected to the circulating medium in the pipeline.
The gate of the gate valve has two sealing surfaces. When the gate valve is closed, the sealing surface of the gate can be pressed against the seat on one side by the pressure of the medium to achieve sealing, which is self-sealing. The gate is basically a forced sealing type, that is, when the gate valve is closed, it needs to rely on the external force of the medium to force the gate to the valve seat to ensure the sealing performance of the sealing surface of the gate valve.
Gate valves can be divided into open-stem gate valves and concealed-stem gate valves according to their structural form. The functions of the two structural forms of gate valves are not much different, and the more difference lies in the use environment.
1. The stem of the rising stem gate valve is exposed, and the opening and closing state of the valve can be observed intuitively when the valve is opened and closed, so as to avoid misoperation. But also because the valve stem is exposed, the height of the rising stem gate valve, which is originally large in height, is even greater. Therefore, the rising stem gate valve is suitable for use in places that require a lot of operating space, and is not suitable for working conditions with narrow space.
2. The valve stem of the concealed stem gate valve is inside the valve body, so the on-off state of the valve cannot be directly observed, and another indicating device is required. However, because the valve stem is in the valve body, the volume of the dark-stem gate valve is smaller than that of the open-stem gate valve, and it is more suitable for use in occasions where the operating space is small and the location is limited and the pipeline is dense.
When the gate valve is fully opened, there is no obstruction when the medium flows through the inside of the valve body passage, and the flow resistance is almost zero. In addition, the valve body channel of the gate valve is symmetrical on both sides, the medium can flow in both directions, and it is not affected by the flow direction of the medium during installation. The gate valve has a wide range of applications due to its good manufacturing process. Gate valves have a wide range of uses, and are widely used in water conservancy systems, water supply and drainage systems, as well as petroleum, chemical, electric power, urban construction, and fire protection 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

Video of resilient seated gate valve:

How many types of gate valves? gate valve classification

January 6, 2022

How many kinds of gate valves are there? Which gate valve is suitable for which occasion? How many kinds of gate valves are there?

Commonly used gate valves are as follows:

DIN-F4-BB-NRS-soft seated-wedge gate valve-DN100-PN16-copper holding ring-handwheel (3)

1. Gray iron gate valve: including gray iron open rod gate valve and gray iron dark rod gate valve, this gate valve is suitable for municipal construction, water treatment, water supply and drainage, water conservancy engineering and other fields.

2 ductile iron gate valve: usually for soft seal gate valve, and divided into exposed rod and hidden rod. This kind of gate valve is mainly used in sewage treatment, building fire control, water supply and drainage engineering and other municipal engineering pipeline.

Gray cast iron gate valves and ball valve gate valves are cast iron gate valves. These gate valves are mostly used in normal temperature and low pressure pipelines, and the medium used is mostly water.

3 carbon steel gate valve and stainless steel gate valve: these two kinds of gate valves are used in high temperature and high pressure pipelines, the use of medium for steam, oil and so on. Applications include petroleum, chemical, metallurgy and so on.

4. Knife gate valve: suitable for all kinds of fluid media such as pulp, mud, sewage, powder, syrup, coal pulp, ash, slag-water mixture, etc.

Knife gate valve (6)

The above are just a few common gate valves. In fact, gate valves are not only the above, according to the structure of gate valves, different standards, connection, drive, etc., can be divided into many types.

According to the structure:

1. Implicit stem gate valve: stem nut is placed inside the valve body, in direct contact with the medium, often fixed on the gate. Through the rotation of the stem, the stem nut drives the lubrication plate up and down to complete the opening and closing.

2. Plain stem gate valve: the stem trapezoidal thread is placed outside the valve body, on the upper part of the stem. By rotating stem nut, stem drives gate synchronous rise and fall, realize valve opening and closing, easy to identify the valve. On and off state to avoid misoperation.

3. Flat gate valve: the sealing face is parallel to the vertical center line, so the valve body is parallel to the sealing face on the gate. This valve is the most common type of double gate.

4. Wedge valve: the sealing face is at a certain Angle with the vertical center line, that is, the two sealing faces are wedge valves.

According to different standards: gb gate valve, American standard gate valve, German standard gate valve, Japanese standard gate valve.

According to the connection mode: flange gate valve, welding gate valve, threaded gate valve.

According to the pressure grade: high pressure gate valve, medium pressure gate valve, low pressure gate valve.

According to the driving mode: electric gate valve, pneumatic gate valve, manual gate valve.

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

Video of knife gate valve:

Video of resilient seated gate valve:

How to judge whether the check valve is qualified in the factory pressure test

January 5, 2022

Check valve refers to the valve that actively opens and closes the valve flap by relying on the activity of the medium itself to avoid the back flow of the medium. It is also called check valve, one-way valve, reverse flow valve, and back pressure valve. The check valve is a kind of active valve whose primary effect is to avoid the back flow of the medium, avoid the reversal of the pump and drive motor, and the discharge of the container medium.

dual plates check valve photos-normal sealing (1)

Check valves can also be used to supply supplementary lines to auxiliary systems whose pressure may rise above the system pressure. The effect of this type of check valve is to only allow the medium to move in one direction and block the movement in the opposite direction. Usually this kind of valve works actively. Under the effect of the fluid pressure moving in one direction, the valve flap opens; when the fluid moves in the opposite direction, the self-coincidence of the fluid pressure and the valve flap will affect the valve seat, and then the movement will be cut off.
Check valves can be divided into swing check valves (rotating according to the center of gravity) and lift check valves (moving along the axis). The swing check valve has a hinge mechanism and a valve disc like a door freely leaning on the surface of the slanted valve seat. In order to ensure that the valve clack can reach the proper position of the valve seat surface every time, the valve clack is designed in a hinge mechanism so that the valve clack can meet the swing space and make the valve clack truly and comprehensively touch the valve seat. The valve clack can be made of metal, or inlaid with leather, rubber, or covered with a composition, depending on the requirements of performance. When the swing check valve is fully opened, the fluid pressure is almost unblocked, so the pressure drop through the valve is relatively small.
The valve disc of the lift check valve is located on the sealing surface of the valve seat on the valve body. Except that the disc can be lifted and lowered freely, the rest of the valve is the same as a shut-off valve. The fluid pressure lifts the disc from the sealing surface of the valve seat, and the backflow of the medium causes the disc to fall back to the seat and cut off the movement. According to the operating conditions, the valve disc can be an all-metal structure, or it can be inlaid with a rubber pad or a rubber ring on the disc holder. Like the stop valve, the passage of fluid through the lift check valve is also narrow, so the pressure drop through the lift check valve is larger than that of the swing check valve, and the flow rate of the swing check valve is restricted. rare.

all types of check valve and structures -code names-photos

Check valve experiment status
The flap axis of the lift check valve is in an orientation straight with the horizontal; the channel axis of the swing check valve and the flap axis are in an orientation approximately parallel to the horizontal line.
In the strength test, the test medium is introduced from the inlet end to the specified value, and the other end is closed, and the valve body and bonnet are qualified without leakage.
In the sealing test, the test medium is introduced from the outlet end, and the sealing surface is checked at the inlet end. No leakage at the packing and gasket is qualified.

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

Video of dual plate wafer check valve:

What is a fluorine-lined valve? How to extend the service life of it?

January 4, 2022

Fluorine-lined valves are made by using PTFE resin (or profile processed) to be molded (or inlaid) on the inner wall of the steel or iron valve pressure part or the outer surface of the valve inner part, and use its The unique performance of the anti-corrosive medium valve is made into various types of valves and pressure vessels.

Fluorine lined butterfly valve-PTFE-WAFER (10)

Among anti-corrosion materials, polytetrafluoroethylene has incomparable excellent performance. In addition to molten metal, elemental fluorine and aromatic hydrocarbons, it is used in various concentrations of hydrochloric acid, sulfuric acid, nitric acid, aqua regia, organic acids, strong oxidants, and concentrated , Alternate dilute acid, alternate alkali, and various organic agents are all reacting spontaneously. The inner wall of the valve is lined with polytetrafluoroethylene, which not only overcomes the shortcomings of low strength of polytetrafluoroethylene material, but also solves the corrosion resistance of the valve theme material. Poor performance and high cost. In addition to its excellent chemical stability, PTFE has good antifouling, anti-sticking properties, extremely low dynamic and static friction coefficients, and good anti-friction and wet performance. Use it as a valve opening and closing sealing pair, and it is necessary to reduce the sealing surface The friction force between the valve and the operating torque of the valve is reduced, and the service life of the product is increased. The scope of its application can also be extended to the food and pharmaceutical industries.

Fluorine-lined valves are also known as anti-corrosion valves. They are often exposed to harsh working conditions. They are not toxic and harmful chemicals, or are very corrosive. Various acids and alkalis or organic solvents. Improper use will cause major economic losses and serious problems. as a result of. Correct use and maintenance of the valve can prolong the service life of the fluorine-lined valve. What details can be done to effectively protect it?
1. Before use, carefully read the fluorine-lined valve instruction manual.
2. Use according to the pressure, temperature, and use medium specified on the nameplate or in the manual.
3. When using, prevent the fluorine-lined valve from generating excessive pipeline stress due to temperature changes, minimize temperature changes, and add U-shaped expansion joints before and after the valve.
4. It is forbidden to use levers to open and close the fluorine-lined valve. Pay attention to the opening and closing indication position and limit device of the fluorine-lined valve. After opening and closing are in place, do not forcefully close it to avoid premature damage to the fluorine plastic sealing surface.
5. For some media that are unstable and easy to decompose (such as the decomposition of some media will cause volume expansion and abnormal pressure increase in working conditions), which will cause valve damage or leakage, measures should be taken to eliminate or limit the factors that cause unstable media to decompose . When selecting the valve type, the fluorine-lined valve with automatic pressure relief device should be selected in consideration of the changes in working conditions that may be caused by the unstable and easy decomposition of the medium.
6. For fluorine-lined valves on pipelines with toxic, flammable, explosive, and highly corrosive media, it is strictly forbidden to replace the packing under pressure. Although the fluorine-lined valve is designed to have an upper sealing function, it is not recommended to replace the packing under pressure.
7. For pipelines with spontaneous flammable media, measures must be taken to ensure that the ambient temperature and working condition temperature do not exceed the spontaneous ignition point of the media to prevent the danger caused by sunlight or external fire.

Applicable medium: various concentrations of acid-base salts and certain organic solvents.
Features: It is the most ideal anti-corrosion material in the world at present, and it has been widely used in the lining of large-scale rotary forming equipment and pipe fittings.

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

Video of PTFE butterfly valve:

Structure of Triple Eccentric Metal seated Butterfly Valve (Picture)

December 31, 2021

Butterfly valves can be divided into soft-sealed butterfly valves and metal seated butterfly valves according to the sealing form. This article mainly analyzes the structure of the triple eccentric metal seated butterfly valve. Metal hard seal butterfly valves are usually used in some high temperature and high pressure environments. They are mainly composed of valve body, butterfly plate, valve shaft, valve seat, butterfly plate sealing ring, shaft sleeve, self-lubricating bearing, driving device and so on.

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

The triple eccentric metal hard seal butterfly valve is a high-performance butterfly valve. It drives the rotation of the valve shaft through various driving devices, and the valve shaft drives the butterfly plate to rotate within the range of 0-90° in the valve body passage to achieve the valve opening and closing. The purpose is to realize the control of the medium flowing in the pipeline. Because of its super high performance, the triple eccentric metal hard seal butterfly valve can be widely used in the pipelines of generators, steam, hot and cold air, chemical smelting engineering, power generation, environmental protection, etc. The applicable media include various corrosive and non-corrosive fluid media. .

Structure diagram of triple eccentric metal seated butterfly valve
Insert “154-1 Picture”

Structural features of triple eccentric metal seated butterfly valve
①Unique and novel three-way eccentric design, frictionless transmission between sealing surfaces, greatly prolonged valve life.
②The elastic seal is produced by the torque, which improves the sealing performance of the valve.
③The wedge-shaped design allows the valve to be closed tighter and tighter, realizing automatic sealing, and the sealing surfaces directly compensate each other to achieve zero leakage.
④The drive mode of the valve can be selected according to the needs of customers, such as equipped with pneumatic and electric devices.
⑤ Only need to change the material of the parts, the valve can be applied to different media, and it can also be lining anti-corrosion (lining F46, GXPP, PO, etc.).
⑥The sealing ring is made of stainless steel, and it has the advantages of metal hard seal and elastic seal. It can achieve good sealing performance regardless of low temperature environment or high temperature working conditions.

If you want to know more about the triple eccentric metal seated butterfly valve, please pay more attention to the official website of “Tanghai Valve”. If you have any valve requirements in this area, you are also 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

Video of triple eccentric butterfly valve:

Application of double eccentric butterfly valve and triple eccentric butterfly valve

December 29, 2021

Butterfly valves can be divided into centerline butterfly valves, single eccentric butterfly valves, double eccentric butterfly valves and triple eccentric butterfly valves. These butterfly valves are widely used in our production and life. Because of some defects of the centerline butterfly valve itself, it is not suitable for the environment where the temperature and pressure are too high or too low, so the butterfly valve is continuously improved, and this is the new design of single eccentric, double eccentric, and triple eccentric. Improvement is a breakthrough. Nowadays, the

Double eccentric-lug butterfly valve-D72F-150lbP-stainless steel (4)

application range of double eccentric butterfly valve and triple eccentric butterfly valve is wider and wider. This article will introduce the application of double eccentric butterfly valve and triple eccentric butterfly valve.

Application of double eccentric butterfly valve
The double eccentric butterfly valve is designed with eccentric structure and is widely used in the fluid pipeline system of water supply and drainage, sewage, construction, petroleum, chemical, textile, paper, hydropower, metallurgy, energy and other projects for regulation and interception.
Under normal circumstances, the seat material of the double eccentric butterfly valve is made of tetrafluoroethylene, which can effectively prevent corrosion. In addition, metal sealing seat can also be used to adapt to the high temperature environment. However, the double eccentric butterfly valve adopts metal sealing seat. The sealing surface of the butterfly plate and the seat is in line contact. The seal is a positional sealing structure. This sealing structure cannot withstand high pressure. If used in high pressure conditions, it will cause a lot of leakage. Therefore, do not use double eccentric butterfly valves with metal seal seats in high-pressure working environments or systems that require tight shut-off.

Application of triple eccentric butterfly valve

triple eccentric butterfly valve-lug

The triple eccentric butterfly valve is currently the most technologically advanced butterfly valve. It not only absorbs the advantages of other butterfly valve products, but also avoids the shortcomings of other butterfly valves, and has been valued by more and more users and technicians. The triple eccentric butterfly valve has a lot of leeway in the selection of sealing materials, and can deal with corrosive media such as high and low temperatures and various acids and alkalis. In addition, the triple eccentric butterfly valve can achieve zero leakage and is particularly suitable for making large-diameter valves. When used as a cut-off valve, it can replace gate valves and ball valves; when used as a flow adjustment, it can replace bulky shut-off valves.
At present, triple eccentric butterfly valves are used in important pipelines in large industrial fields such as petroleum exploration, petroleum refining, petrochemical, and energy power generation. As people continue to study, it is believed that triple eccentric butterfly valves will be applied to more and more fields.
If you want to know more about double eccentric butterfly valve and triple eccentric butterfly valve, please visit the official website of “Tanghai Valve”. If you have valve requirements in this area, you are also welcome to inquire and order.

TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D.
Video of center-lined butterfly valve: https://youtu.be/NuSZH_AJcwY
Video of double eccentric butterfly valve: https://youtu.be/yOw2xp3bIaE
Video of triple eccentric butterfly valve: https://youtu.be/AkRwg2X1Wh0

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