Every industry has a demand for sanitary fittings, but the pharmaceutical industry takes the crown in this race. There is very little margin of error in this industry, as we are talking about medicines. Medicines that cure our headaches, medicines that save our life! As it is evident, the standard sanitary fittings aren’t meant for manufacturing drugs. Hence, there is a need for biopharmaceutical sanitary valves, which we are going to discuss in this brief. Biopharmaceutical fittings (BPE) are a perfect solution to this problem.

The Difference Between Sanitary Valves and Industrial Valves

On the face of it, there seems to be very little difference between biopharmaceutical fittings and 3A sanitary fittings. However, there are some critical differences in the styles of the two fittings that set them apart. The BPE fittings comply with the ASME-BPE standards. It is pertinent to mention it again that sanitary valves play a critical role in the production of pharmaceutical products. Therefore, it is natural that these vales feature high tolerance and clean interior surface finishes. This is in contrast to standard fittings. Furthermore, material requirements are a lot different than 3A sanitary standards. 3A standards are industrial valves that find plenty of uses in industries like food, beverage, and dairy.

What are the Main Types of Sanitary Valves?

Fun fact: It is possible to build sanitary valves with thousands of variations! However, for the sake of convenience, we can classify sanitary valves into three key types. This classification is made on the basis of their mechanical motions. These three classes are linear motion, rotary motion, and quarter-turn valves. Let us talk about them briefly in the following lines of this brief:

1.    Linear Motion Valves

These valves use a closing member. As they move in a straight line, they permit, stop or choke the medium’s flow. You might have come across some types of linear motion valves already. These include gate, diaphragm, pinch, lift check valves and globe valves.

2.     Rotary Motion Valves

In this type of sanitary valve, a valve closure member is used. It is this valve that permits motions on the cylindrical or angled paths. Some of the common types of rotary motion valves include ball, eccentric, swing check, and butterfly valves.

3.    Quarter Turn Valves

In essence, these are just like rotary motion valves. The key point to note here is that these valves require only a quarter-turn stem motion to switch their positions between fully open and fully closed.

An important that must be kept in mind is that a sanitary valve is defined by a set criterion. Unless these special sterile requirements are met, a valve cannot be deemed sanitary.

Let us talk a bit about the sanitary ball valves and butterfly valves in this space as well. Coming towards the sanitary ball valves first, well, they use a ball with a hole that is drilled through the middle swivel mounted to the valve body. The sanitary ball valves operate at their maximum when the ball is in line with the pipe. However, it is quite possible to rotate the hole in the ball away from the pipe’s direction. This chokes the flow rate. It is cut off completely once the hole is at 90 degrees in the pipe direction.

Often, there is a question about the nature of the butterfly valves. Do they have a place in the sanitary club or not? The answer is, yes, of course, they are sanitary valves. They feature a single eccentric structure. Their soft seal is predominantly different from the middle section. Their characteristic features are compactness, lightweight and minimalistic composition.

Who Uses Sanitary Valves and Why?

Now, let us talk a bit about the end users of sanitary valves. Usually, biopharmaceutical sanitary valves are used by folks concerned with the pharmaceutical industry, biotechnological facilities, and certain other purity industries. What makes them suitable for use in these industries? Let us find that out in this section of the discussion!

In medical industries, contamination is the last word you would want to hear. We don’t need to build on why it is a taboo word there, right? Now to the real point, if there are services in the valves, then the chances of contamination increase by a significant factor. So ideally, valves that come without any services sound like a perfect pick for industries that we have mentioned in the earlier lines of this brief, right? Guess what? Sanitary valves come without any services! So that contamination problem is solved alright, what do you think?

Cleaning is cumbersome sometimes. When we are talking about mega industries like the pharmaceutical industry, then we need to pay more attention to streamlining the process. That’s where sanitary valves save the day. Because they are not stained easily, they are a super convenient option. Now you might not realize it at first, but the extensiveness of the process is directly proportional to the amount of cleaning that needs to be done afterward!

Sanitary valve manufacturers in USA are making gold as they are a perfect pick for anyone who is weary of polishing and smoothing valves all the time. Do you know who that is? Pharma boys! Rust is enemy number one in all such settings. It can complicate things to a great extent. Hence, sanitary valves are a perfect pick again because they are made of polished stainless steel.

Standards & Certification

ASME-BPE

ASME has a BPE committee that acts as a governing body for BPE standards. The ASME-BPE standard is concerned with all aspects of BPE fittings. These aspects include tolerances, interior surface finishes, product markings, composition, and packaging. BPE certification implies that ASME has conducted an audit of a company. Companies that hold ASME-BPE certification can proudly flaunt that they are meeting the required standards. Such audits are a must for compliance. Companies who undergo the said audits have permission to label their products with ASME certification marks.

One of the key requirements of ASME-BPE standards is that the BPE fittings must be consistent in terms of dimensions. It doesn’t matter who is producing them; the manufacturer becomes an irrelevant topic in this discussion. Then, these sanitary valves must also come with specific permanent markings on the outside of the fittings. These markings include heat number, material type, company, manufacturing country, surface finish, and the letters BPE inscribed on them.

An important question that arises here is: how is material verification performed in the case of BPE fittings? Well, it is done so by using a niton gun. Thanks to this clever invention, identifying a fitting in terms of its chemical composition is fairly easy. All that it takes is a single click! Performing this identification is extremely important since, without it, one cannot be sure about the materials that the end-users are getting.

Traceability

Traceability is one of the most important factors when we are talking about BPE fittings. It is absolutely essential that the chemical and mechanical make-up of the materials must meet the set criterion. Otherwise, the sanitary valves in question will not be given the due nod of approval. Here, talking about heat numbers is a must; they identify the manufacturing lot of the steel. Normally, heat numbers are marked on the outer side of the sanitary valves. Heat numbers must match up with the corresponding paperwork. This corresponding paperwork is dubbed Materials Test Reports. It serves as proof that the sanitary valves meet the specified standards.

MTR

Let us talk about Material Test Report (MTR) in this domain as well. It is an official piece of documentation from the mill; it specifies the mechanical and chemical properties of the steel. Its importance in material traceability and verification cannot be ignored. The MTR must be provided with every sanitary valve. Sanitary valve suppliers need to take care of these parameters.

Conclusion

So, that would be all from this brief. As it is evident from these lines, the biopharmaceutical sanitary valves have critical importance in medicine and related pharmaceutical industries. Precision and fine finishes are key parameters that distinguish them from their industrial counterparts. To ensure that nothing wrong has happened throughout the process, documentation and packaging have been given due weightage as well. It is these major points that allow users to trace back products to inception. Once the understanding is at the most perceptive level, users can easily pick the sanitary valve that is the requirement of the process.

Today, the industrial web is bigger than ever. It is getting more and more specific with every day passing. Biopharmaceutical industries needed something safer and more efficient to solve their quality woes and concerns. Sanitary valves are the answer, as it seems!

The post The Ultimate Guide to Bio-Pharmaceutical Sanitary Valves appeared first on Adamant Valves.

What are Diaphragm Valves?

Diaphragm valves are bi-directional on-off throttle valves. They control the flow and speed of fluids through an area. Diaphragm valves regulate the area through which fluids enter or exit the system. The name diaphragm comes from a thin and flexible membrane that moves up and down within the valve’s body, causing it to open and close. Diaphragm valves can be made from plastics, single-use materials, and stainless steel. Stainless steel Diaphragm valves are easy to maintain, and they are clean and leak-proof.

How Do Diaphragm Valves Work?

Diaphragm valves are pretty similar to pinch valves in the way they work. The valve has a linear compressor that pushes the thin diaphragm into contact with the valve’s body. When the user decides to shut the valve, the actuator is pressed or turned, pushing the membrane to the edge of the valve, thus closing the valve.

Criteria for Selecting a Diaphragm Valve

You may encounter some problems specifying the correct valve size to use as there are no industry standard diaphragm valves. Below are some parameters you can consider when purchasing a diaphragm valve, so you can make the right choice.

● Valve size: The size of the valve is important since they have different throttling applications. As such, the size of the valve has a way of affecting the control of the fluids. To get the right valve size to use, ensure that the volume of the process fluid moving through the system is known. Hence, it’s important to know the state of the liquid, how it flows, as well as the viscosity and specific gravity of the fluid. Endure to also know the inlet and outlet pressures and temperatures.

● Deciding the Type of Actuator to Use: The actuator type will determine the size of the diaphragm valve you should select. Actuation types include electric motor, thermal, pneumatic, hydraulic, etc. This factor determines how the valve is opened or closed. The type of actuator you use depends on the force of the fluid flow through the system.

Advantages of Using a Diaphragm Valve

1. It serves as an on-off and throttling service valves
2. There is no case of stem leakage when using the diaphragm valve
3. The diaphragm valve provides tight bubble service
4. There are no pockets that trap impurities, slurries, and other solids.
5. Diaphragm valves have suitable linings that are resistant to chemical attacks.

Disadvantages of the Diaphragm Valve

1. Diaphragm valves are not suitable for use where the temperature is below -60 or more than 450 degrees Fahrenheit.
2. It is also not suitable for use in a flow system, where the flow pressure is more than 300psi.
3. Diaphragm valves are not ideal for use in multi-turn operations

Application of Diaphragm Valves

Diaphragm valves are used in different industries because they are cheap, very effective, and made in different sizes and forms. Below are some common places where the diaphragm valve is of importance:
1. Power industry
2. Vacuum services
3. Breweries
4. Corrosive applications
5. Water treatment facilities, and
6. Pharmaceutical manufacturing systems

What Are Butterfly Valves?

A butterfly valve controls fluid flow using a rotating circular plate or two hinged semicircular plates attached to a transverse spindle and mounted on a pipe to prevent or control flow. Butterfly valves are used mainly in places with limited space. They are very easy to operate and they open fast, with just a 90-degree rotation of the handle that will cause the valve’s complete opening or closure.

Advantages of Using Butterfly Valves

1. They are relatively light in weight
2. Butterfly valves work well in small spaces since they have a compact design
3. Have low-pressure drop and high-pressure recovery
4. They are used to provide bubble-tight service

Disadvantages of the Butterfly Valve

1. The butterfly valve leaves residual materials in the pipeline.
2. The flow turbulence affects the movement of the disc.
3. Sometimes, the thickness of the valve may restrict the fluid flow.
4. Thick liquids can sometimes prevent the disc from moving freely.

Application of Butterfly Valve

Some common applications where the butterfly valve offers effective control includes:
1. Vacuum service
2. Slurry and similar services
3. High pressure and high-temperature water and steam services
4. Compressed air or gas applications
5. Cooling water, air, games, and fire protection.

The most significant difference between the butterfly and diaphragm valves is their valve elements. The diaphragm valve uses a thin, flexible membrane, whereas a butterfly valve uses a circular plate that controls fluid flow by closing and opening.
Are you in search of top-quality valves for your system? Visit Adamant valves to get high-quality sanitary valves, including stainless steel diaphragm valves, butterfly valves, pneumatic valves, and electric valves for different flow systems. Feel free to call us today at (949) 407 8897 to reach our experts and get the perfect valve for your system.

The post Difference Between Diaphragm Valve and Butterfly Valve and Their Different Areas of Application appeared first on Adamant Valves.

A sanitary valve for powders is widely used in many industries.

A customer of Adamant Valves has a wide range of products, including organic infant formulas, organic follow-on milk, organic milk, organic cereals, allergenic formulas, milk-free infant formulas, dietetic baby food, probiotics, and polyunsaturated fatty acids.

Butterfly Valve for Powders

The drive for innovation has necessitated the requirements of extraordinary accuracy in production and packaging. The company, from a technological point of view, classifies itself somewhere between a dairy and pharmaceutical products and pays the highest attention to the selection of sanitary components for its process.
Sanitary diverter valves and sanitary butterfly valves play an important role in powder conveying.

How to convey powders for sanitary valves in the materials handling industry?

In a typical wet blending/spray drying process for infant formulas and powders, ingredients are blended with water in large batches and then pumped to a heat exchanger for pasteurization. After pasteurization, the liquid is homogenized and the product may be concentrated by passing it through an evaporator or sent directly to the spray dryer.

the product is then atomized in the spray dryer. As droplets of products are fluidized in the dryer, water is evaporated, and then dry powder drops to the bottom of the spray dryer, where it is discharged with a sanitary butterfly valve to a fluidized bed.

As droplets of products are fluidized in the dryer, water is evaporated and then dry powder deposits drop to the bottom of the spray dryer. There the product is typically dried further and cooled. The outlet air from the spray drying chamber still carries product (fines) which is normally ducted into cyclones and bag filters after the spray dryer. From there the product is discharged with sanitary shutoff valves into the fines return line.

The fines can either be transported by conveying pneumatically to the fluidized bed or back to the top of the spray dryer for agglomeration purposes. The actual conveying path is selected by the sanitary valve. After the fluidized bed, the finished powder passes through a sifter and is then pneumatically conveyed to storage silos or packaging lines, where it is deposited into bags or where it is canned.

Moisture and warm temperatures in the wet blending and spray drying process are conducive to bacterial growth. Therefore wet cleaning is normally applied in this process while dry cleaning is often typical in the process after the fluid bed dryer.

What are the features in the design of Adamant sanitary butterfly valves for powders?

It is designed for the delivery of a split open and closed valve by using the principle of compressed air to realize sealing. The valve is the ultra smaller torque and longer life standard than other normal butterfly valves.

What distinguishes sanitary valve components is the gap-free design, especially in critical areas, such as inlet flanges or side cover gaskets. This is very important when the production plants are cleaned wet, in order to prevent product deposits and also humidity residues in gaps.

The post 3 Things You Should Know About Sanitary Valve for Powders appeared first on Adamant Valves.

The aim of using a butterfly valve is for isolating or regulating the flow of liquid. The closing technique takes the form similar to a disk. All the operation is similar to that of a ball valve, where a quick shut-off is there to regulate the flow. Usually, people prefer butterfly valves as they are inexpensive as compared to other valves due to their lightweight. A butterfly valve needs less support to function.

Here in butterfly valve sanitary, a circular pipe is attached which controls the flow of material through a circular pipe or tube. Usually, the materials for which a butterfly is used are air, gas, steam, or liquid. It can be also be used for certain dry materials.

Butterfly valves are quick opening valves associated with a metal circular disc along with its pivot axes at right angles. It regulates the direction of the flow of the pipe. It works with the mechanism that when it is rotated on a shaft, it seals against seats in the valve body. The butterfly valves are normally used as throttling valves to control flow. The high-performance butterfly valves do not have any pockets where the fluids may get trapped while the valve is closed.

This type of valve is one of the most compact, as well as lightweight valves, that exist on the earth. It has a wide range of applications. This kind of valve is more popular due to the choice of the seat as well as the lining. Moreover, the disc options have significantly enhanced the demand for the same over the latest years making the valve a smart alternative.

Being full of all the favorable qualities like the wide range of materials with desired sizes and pressure ratings offers reliable and positive isolation with moderate flow control potential more than a wide range of applications all the way through the valve industry.

The petrochemical trade and oil industry use this metal seated valve because they are fire safe, lightweight as well as perfectly suitable for actuation. If used for the appropriate application these butterfly valves offer you a great number of advantages. It is suitable for chemical services. The main advantage of the valve is that it can be used where space is less. It is designed to be used with small dimensions.

The post What is Butterfly Valve Working Principle? appeared first on Adamant Valves.

On the large semi-circle rotating in a long radius, the tangent of rotation trajectory of butterfly plate sealing surface will form an angle with the sealing surface of the valve seat, which makes the sealing surface of the butterfly plate completely break away from the sealing surface of the valve seat so that the relative mechanical abrasion and the squeezing angle stroke between the butterfly plate and the sealing surface of the valve seat are much shorter during the process of opening and closing of sanitary butterfly valve.

When the butterfly plate rotates from 0 degrees to 8~12 degrees, the mechanical abrasion and deformation from squeezing are further lowered, and the sealing performance and service life are further improved.

The features of wafer butterfly valve:

1. This valve can be designed into a flange connection and clamp connection.

2. Actuating method can be manual, electric, or pneumatic.

3. The use of a “U” shape stainless steel sealing ring. The valve seat has a certain degree of elasticity. Whether in high-temperature or low-temperature situations, the valve and the butterfly plate both have excellent sealing performance.

4. It is a metal-to-metal linear sealing butterfly valve. The sealing surface of the butterfly plate uses soldered stainless steel or hard alloy. The sealing surface is abrasion-resistant and has a long service life.

5. This butterfly valve has excellent sealing performance and is high-temperature resistant, pressure-resistant, abrasion-resistant, and corrosion-resistant.

The post The Structural Features of Wafer Butterfly Valve appeared first on Adamant Valves.

1. Quick.

The grooved clamp is used for contact and a corresponding pipe is used for pipeline placement. No welding, no second galvanization, no second placement. The placement rate is raised.

2. Lightweight.

Clamp contact is lightweight, the number of bolts is small, the placement is easy, no extra skills are needed.

3. Reliable.

Scientific and rational design of parts and unique C-type rubber sealing ring have the effect of triple sealing, which ensures the reliability of the joint sealing.

4. Safe.

The grooved clamp is used for contact and the corresponding pipe is used for pipeline placement. Only mechanical assembly is needed. No need for welding and no open flames. Therefore, there’s no slag to pollute the pipeline, which ensures the site’s safety. It’s particularly suitable for working under fire-free conditions.

5. Economical.

Due to the easy and quick placement, no need for extra skills, low repair rate for placement, the overall placement cost can be 30-50% lower than that of the flange type.

6. Occupies small space.

The space occupied by grooved clamp contact is about 70% of that of the flange type. And because the number of fastening bolts is small, it is particularly suitable for working in a crowded space.

7. Easy maintenance.

As long as the placement is appropriate, the pipeline passes the pressure testing immediately. No need for regular maintenance and no need to change the spare parts for decades.

8. Common practical pipes.

Grooved clamp contact can be used to connect metal pipes such as seamless steel pipe, galvanized steel pipe, welded steel pipe, stainless steel pipe, brass pipe.

9. Flexible connection of the pipe can be achieved.

The pipelines connected by flexible grooved clamp contact are flexible systems. They can absorb the displacement caused by temperature changes, allowing the pipe to have a certain offset angle.

Conclusion

Thank you for reading our article and we hope it can help you better understand the features of clamp-type butterfly valves. If you want to learn more about clamp-type butterfly valves, we would like to advise you to visit Adamant Valve homepage for more information.

The post The Features of Clamp Type Butterfly Valves appeared first on Adamant Valves.

Although there are thousands of online publications online about valves, the reality is that most of them provide biased information. When it comes down to choosing the right valve, you need to be extremely careful. This is so because you don’t want to buy a valve that will break down a few days later.

Getting information about the different types of valves is essentially important in finding the right valve. Here, we are going to talk about pneumatic sanitary threaded butterfly valves.

A Pneumatic sanitary threaded butterfly valve is widely used in isolation and control of the medium in piping systems. This valve has also been designed to operate automatically. Pneumatic sanitary threaded butterfly valves are widely used in the pharmaceutical, chemical, beverage, food, and brewing industries. This is so because it is easy to clean and mainly used for sanitary purposes.

The main difference between this valve and other butterfly valves is that this one has been designed for sanitary purposes. The valve not only allows a smooth flow of media but also comes with a low maintenance cost. A large number of industries are now using this valve because it comes with lots of benefits. The food, as well as brewing, pharmaceutical, and beverage industries, are now considering sanitary valves among some of the most important industrial applications.

These valves are normally small in size and when actuated pneumatically, they can close and open very quickly. This makes it very easy to achieve a perfect shutoff. As compared to a ball valve, this valve has a lighter disc which means that it needs less structural support.

Pneumatic Sanitary Threaded Butterfly Valves are also precise which makes them the best in industrial applications. They also have a low maintenance cost and are easy to operate. This valve is simply the best choice for anyone who wants a reliable and efficient valve. The fact that this valve is constructed using stainless steel; is the ideal valve for use in the food, beverage, and brewing industries. It`s much easier to clean as compared to other butterfly valves in the US market.

The post Finding the Right Sanitary Threaded Butterfly Valves appeared first on Adamant Valves.

The electric butterfly valve is composed of an electric actuator and butterfly valve, so it has the advantages of easy operation and simple structure commonly seen in sanitary butterfly valve. It can also be widely used in chemical, pharmaceutical, and other industries. And because of the electric actuator, the development of the butterfly valve reaches a new level. The mechanism of the electric butterfly valve: The valve stem is driven by electric devices, which makes the butterfly plate rotate 90 degrees to open or close the valve.

The mechanism of the electric actuator

The mechanism of the electric actuator is actually quite simple. It’s just like the razor that we use daily. The energy source is electricity, which leads to the operation of the valve plate, achieving the opening and closing of the valve and connecting or shutting off the fluid.

The electric actuator of the electric butterfly valve can be divided into switch type and regulation type. The switch-type electric butterfly valve simply plays the role of switching. The regulation-type electric butterfly valve is to plays the role of regulating the flow. It can accurately adjust the flow to the thousandth of degrees. However, it’s also a kind of valve that is relatively expensive.

Valve is a kind of device installed inside the pipelines. To check the state of the switch on the field doesn’t seem very practical, so we have feedback signals. The regulation type itself as feedback signals. According to specific user requirements, feedback signals can be installed.

Storage method of electric butterfly valve:

1. This product should be stored in a dry and well-ventilated room. It should not be stored outdoors. The sealing ring should not be in contact with oily substances so that aging can be avoided.

2. Storage and transportation: lids are used at both ends of the diameter to prevent dust and rust and to keep the channels clean. At both ends of the processing surface, dirt should be removed and rust inhibitors should be coated.

3. For an electric butterfly valve whose storage period is over 18 months, before installation and use, we should re-test it to ensure the integrity of the structure and function.

4. When placing an electric butterfly valve, make sure the electric device doesn’t get crushed and the terminals don’t get damaged, and avoid contact with corrosive substances. Be careful when handling to avoid damage to electrical and mechanical parts.

The post How Does an Electric Butterfly Valve Work? appeared first on Adamant Valves.

A sanitary butterfly valve is a quarter-turn valve that goes from fully open to fully closed by rotating only 90 degrees. Butterfly valves help you regulate the flow of fluid within large-diameter piping by changing the deflection angle of the butterfly plate. The central disc is held in place by a rotating rod connected to an actuator that controls the disc’s open-close movement. These valves can be used to cut off flow completely or regulate the flow rate.

Where are Butterfly Valves Used?

The butterfly valve is suitable for large-capacity pipelines transmitting various corrosive and non-corrosive fluid mediums in applications like furnaces, gas lines, petroleum processing, liquefied petroleum gas pipes, hot and cold air, chemical smelting, power generation, environmental protection, construction, water treatment, and other engineering systems. It is used to regulate and cut off the flow of the medium.

How are Valves Tested?

Valves are pressure vessels that must meet stringent requirements to bear medium pressure without leakage. The valve body, valve cover, and other critical components must be free from cracks, loose pores, slag, and other defects that affect the strength.

There are several valve tests that can be completed throughout the production process. It’s important to conduct valve testing at each step, from design, to manufacture, installation, operation, and maintenance. However, the most important valve tests are conducted before the valve leaves the factory. Quality assurance specialists perform multiple close appearance inspections and valve-specific performance tests to expose any defects and make adjustments accordingly. Only after all the tests are qualified can the product be put into use. 

What is the Correct Pressure Test Method?

Pneumatic butterfly valves have the same strength test requirements as shut-off valves. To test a butterfly valve’s sealing performance, the test medium should be introduced from the medium inflow end. Make sure the butterfly plate is opened, the other end closed, and inject the test medium at the pressure specified by your testing requirements.

After ensuring there is no leakage at the stuffing and other sealed parts, close the butterfly plate. Open the other end, if there is no leakage at the butterfly plate’s sealing, it is considered qualified. The butterfly valve that is used for flow regulation can skip the sealing performance test.

The post How Do You Test a Butterfly Valve? appeared first on Adamant Valves.

When this force is directed to the valve stem screw thread, it’ll become difficult to open the valve again. Therefore, the torque required to open the valve (namely the torque applied to the valve stem nut) is usually bigger than the torque required to close the valve.

In addition, for a pair of sealing surfaces that is in contact with each other, the coefficient of static friction is bigger than that of kinetic friction. So to make the sealing surfaces have a relative displacement from the stationary state, a large force must be applied to overcome the static friction force. This is more evident in valves that are opened again after being closed.

Because temperature changes make the pressure between sealing surfaces bigger and the static friction force needed to be overcome also increases, when the valve re-opens after being tightly closed, the torque needed to be applied on the valve stem screw thread is bigger, sometimes much bigger, than the torque needed to close the valve.

There are some gate valves or flange sanitary butterfly valves whose valve stem screw thread is on the gate plate, hand wheel or electronic device drives the valve stem to make the gate plate move up and down, the valve stem only makes rotation movement with no lifting movement. Such a gate valve is called a dark stem gate valve or rotary stem valve.

The post Precautions on Closing Turbine Double Flange Butterfly Valve appeared first on Adamant Valves.