Skype: jeany5678 ------ What's app:86 151 5776 6245 ------ Email: [email protected]

Archive for category: Industry News

You are here: Home / Industry News

Read news issued by STV Valve Company and acquire more comprehensive information about Company, latest valves and valve industry progress

what is the torque of API 600 gate valve

/in /by

The torque of API600 gate valve is the opening torque of the valve (valve torque). Unit: Newton. Meter.

Opening torque, also known as operating torque, is the most important parameter for selecting valve driving device. The opening torque is also another important index to measure the quality of valve products. When people evaluate the quality of valve, it is often described as light and flexible opening of valve. In the pipeline valve standards of some advanced industrial countries, it is regarded as one of the assessment indicators, and it is stipulated that the opening torque of manual valve shall not exceed 360n • M. If this torque is exceeded, it is necessary to consider selecting appropriate driving devices (such as electric, pneumatic and hydraulic devices). Some manufacturers print the opening torque in the product sample to facilitate users’ selection.

Opening torque (torque) refers to the force or torque that must be applied to open or close the valve. When closing the valve, it is necessary to form a certain sealing specific pressure between the opening and closing parts and the two sealing surfaces of the valve seat. At the same time, it is also necessary to overcome the friction between the valve stem and the packing, between the threads of the valve stem and the nut, and between the end support of the valve stem and other friction parts. Therefore, a certain closing force and closing torque must be applied. The opening and closing force and opening and closing torque required by the valve in the process of opening are changed, and the maximum value is at the final moment of closing or the initial moment of opening. When designing and manufacturing valves, try to reduce the opening and closing force and opening and closing torque.

The opening torque can be calculated or measured to obtain approximate results, or measured by torque wrench.

 

 

 

 

 

 

 

 

 

 

 

 

 

For rotating stem valves:
  1. 167 lbf-ft. No. 218 lbf-ft. Yes.
  2. 254 lbf-ft. No. K Add gland friction torque = (1000 x stem diameter^2) ÷12 (2) —- 188 lbf-ft. —- …
  3. 406 lbf-ft. M Actuator RPM = Speed in inches per min ÷ Lead of stem. 12 ÷ 1/3. = 36 RPM. Notes.
Dynamic torque can be calculated from the formula Td = C (ΔP). Here, ΔP is the effective pressure drop across the valve at a given temperature and C is, once again, a constant.
Stainless Steel Gate Valve

What are gate valves

/in /by

Gate valves are valves that have much popularity when it comes to all types of applications and attachments and is therefore suitable for both above-ground and underground installation. When installing gate valves underground, it is vital to pick the appropriate type of valve to avoid high replacement costs.

Gate valves are made for either fully open or fully closed services. They are installed in pipelines, similar check valves, as isolation valves and definitely should not be utilized as regulation or moderation valves. Operation on a gate valve usually occurs doing either clockwise to close or clockwise to open rotating motion of the steam. When operating the valve, the gate moves either up or downwards; not sideways.

Stainless Steel Gate Valve

 

 

 

 

 

 

 

 

 

 

 

 

 

Where are gate valves used?

Gate valves are usually used when free bore and minimum pressure loss are the requirements. When the pipeline is fully open, a typical gate valve has no obstruction in the flow path, which results in an extremely low-pressure loss. This design makes it possible to use a pipe-cleaning pig.

A gate valve is a multi-turn valve, meaning that the operation of the valve is finalized by means of a threaded stem. As the valve has to turn many times to go from an open to a closed position, the operation also stops the effects of the water hammer.

Gate valves can be used for a plethora of different fluids. The products from China Gate Valve Manufacturer are commonly suitable for under the following working conditions:

  • Neutral, wastewater and potable water: temperatures somewhere between -20 and 70+ degrees Celsius, maximum 5 m/s flowing speed, and limited up to 16 bar differential pressure.
  • Any gases: temperatures between -20 and +60 degrees Celsius, maximum flowing speed: 20 m/s flow velocity, and reaching up to 16 differential pressure.

Gate valves with bypass

Bypass gate valves are primarily used for three simple reasons:

  • Delayed filling of pipelines
  • With the main valve closed, and the bypass valve opens, a consistent flow is allowed, preventing possible stagnation
  • To balance the pipeline’s differential pressure, lowering the torque requirement of the valve and allow one-man operations

Parallel vs Wedge-Shaped Gate valves

Gate valves can be divided into two alpha types: Parallel and wedge-shaped. The difference is that parallel gate valves use a flat gate between two parallel (thus where their name originates) seats, and a popular variant is the knife gate valve designed with sharp edges on the bottom of the gate. The wedge-shaped gate valves used two inclined seats and a mismatched inclined gate.

Metal seated vs resilient seated gate valves

Before the resilient seat gate valve was mass-manufactured, gate valves including a metal seated wedge were widely used. The pointed wedge structure and angular sealing devices of a metal seated wedge need a bore of the valve’s bottom to confirm a tight closure. Therefore, sand and pebbles are embedded in the depression. The pipe network will never be fully free from impurities. Regardless of how well the pipe is flushed during installation or repair.

The Knowledge About Parts Of Industrial Valves

/in /by

Industrial valves is a mechanical device that controls the flow and pressure in a system or process. They are an important part of the pipeline system for transporting liquid, gas, steam, slurry and so on. Different types of valves can be provided: gate valve,  ball valve, butterfly valve, check valve, diaphragm valve, pipe clamp valve, pressure reducing valve, control valve, etc. Each of these types has many models, and each model has different functions and functions. Some valves are operated automatically, while others are operated manually or using actuators or pneumatic or hydraulic operation.
The functions of the valve are: stop and start the flow, reduce or increase the flow, control the flow direction, adjust the flow or process pressure, and release a certain pressure.
There are many valve designs, types and models with a wide range of industrial applications. All meet one or more of the above functions. Valves are expensive items, it is important to specify the correct valve for this function and must be made of the correct material for handling liquids.
Regardless of the type, all valves have the following basic components: body, bonnet, trim (internal components), actuator and packing. The basic components of the valve are shown in the figure below.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

valve body

The valve body, sometimes called the shell, is the main boundary of the pressure valve. It is the main component of the valve assembly because it is the frame that holds all parts together.
The valve body is the first pressure boundary of the valve and can resist the fluid pressure load of the connecting pipeline. It receives inlet and outlet pipes through threaded, bolted or welded joints.
The end of the valve body is designed to connect the valve to the pipe or equipment nozzle through different types of end connections, such as butt or socket welding, thread or flange.
The valve body is cast or forged in various forms, and each component has a specific function and is constructed of a material suitable for that function.

Valve bonnet
The cover of the valve body opening is the hood, which is the second important boundary of the pressure valve. Like the valve body, the bonnet is available in many designs and models.
The bonnet is used as a cover on the valve body and is cast or forged from the same material as the valve body. It is usually connected to the body by threads, bolts or welded joints. During the manufacture of the valve, place internal components (e.g. stem, disc, etc.) into the valve body, and then connect the bonnet to keep all components together.
In all cases, the hood to body connection is considered a pressure boundary. This means that the welded joint or bolt connecting the bonnet to the valve body is a pressure retaining component. Although the valve bonnet is a necessity for most valves, it has attracted people’s attention. The bonnet may complicate the manufacture of the valve, increase the valve size, represent a significant cost part of the valve cost, and is a source of potential leakage.

Valve trim
The removable and replaceable internal parts of the valve in contact with the flowing medium are collectively referred to as valve trim. These components include valve seat, disc, gland, gasket, guide rail, bushing and internal spring. The valve body, bonnet, packing, etc. are also in contact with the flowing medium and are not considered as valve internals.
The adjustment performance of the valve depends on the interface between the disk and the valve seat and the relationship between the disk position and the valve seat. Due to decoration, basic movement and flow control are possible. In the rotary motion decoration design, the disc slides tightly across the seat to produce changes in the flow opening. In the linear motion decoration design, the disc rises vertically away from the seat, resulting in an annular hole.
Valve trim components can be made of various materials because different characteristics are required to withstand different forces and conditions. The bushing and packing gland will not be subjected to the same forces and conditions as the disc and seat.
Flow medium characteristics, chemical composition, pressure, temperature, flow rate, velocity and viscosity are some important considerations in selecting appropriate decorative materials. The trim material may or may not be the same material as the body or bonnet.

Valve disc

The disc is the part that allows, throttles or stops flow, depending on its position. In the case of a plug or ball valve, the disc is called a plug or ball. Disks are the third most important primary pressure boundary. With the valve closed, the entire system pressure is applied to the disk, so the disk is a pressure related component.
Discs are usually forged and, in some designs, have a hard surface to provide good wear resistance. Most valves are named for their disk design.

valve seat

The seat or sealing ring provides a seating surface for the disc. The valve may have one or more seats. In the case of ball or swing check valves, there is usually a seat that forms a seal with the disc to prevent flow. In the case of gate valves, there are two seats; One is on the upstream side and the other is on the downstream side. The gate valve disc has two seat surfaces that contact the seat to form a seal to prevent flow.
In order to improve the wear resistance of the sealing ring, the surface is usually hardened by welding and then machining the contact surface of the sealing ring. When the valve is closed, fine surface treatment of the seat area is necessary for good sealing. The seal ring is generally not considered a pressure boundary component because the body has sufficient wall thickness to withstand the design pressure independent of the thickness of the seal ring.

 

ISO5211 Mounting Ball Valve Dimensions

/in /by

For ISO5211 Mounting Ball Valve connection size, most of the actuators are pneumatic, manual, electric and hydraulic operation. The following is the data sheet of flange connection size of American standard butterfly valves.

The flange connection size of American standard butterfly valve is ISO5211. American standard butterfly valve does not need to be explained. It is that the butterfly valve produced by American standard is called American standard butterfly valve. What is the upper flange? It refers to the size of the connecting part of the valve body and actuator. We call the upper flange size. The standard referred to is ISO 5211 international standard.

Most new ball and butterfly valves are now standard with an ISO mounting interface. This simply means that you can mount the actuator directly to the valve without a bracket and drive dog. This saves time, hassle and money. The below shows the dimensions for ISO5211.

 

 

 

 

 

 

 

 

 

Type is the code of the upper flange. In daily communication, we usually use codes like F07 and F10 to represent the connection size
D1 is the outer diameter of the upper flange
D2 is the diameter of the groove on the upper flange. Usually some actuators have a boss, a groove, and a convex groove to start and fix
D3 is the drilling center of the upper flange
D4 is the specification of bolt. Generally, the upper flange of American standard butterfly valve adopts the form of through hole
H1 is the depth of the groove
H2 is generally negligible
The last item is the number of holes
In order to connect the actuator and American standard butterfly valve, in addition to the above dimensions, there are stem dimensions, which can be square centered, round rod with keyway, and the height of the stem exposed from the bracket. With these dimensions, it is the completed dimension, so as to ensure the connection between the actuator and American standard butterfly valve.

 

How to choose the material of sight glass

/in /by

The pipeline sight glass is generally used in the pipeline of industrial production equipment such as crude oil, chemical plant, pharmaceutical industry and food industry. It can observe the fluidity of liquid, vapor, steam, grease and other media in the pipeline anytime and anywhere. It has the effect of monitoring production and preventing safety accidents in the process of processing, STV Valve Technology  thinks it is an indispensable part of pipeline equipment.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

How to choose the material of sight glass

When selecting the material of the main components of the sight glass, the process performance (temperature, working pressure) and organic chemistry (corrosion) of the working medium should be fully considered. In addition, we should also refer to the relevant requirements and regulations of our country and application units.
At present, there are many kinds of materials, suitable for a variety of different media and places. However, due to the limitations of glass window process performance, the corrosion of medium and high cost performance are mainly considered when using materials. Generally, there is no need to consider the working pressure resistance and application temperature of materials. Many raw materials can consider the application requirements of mirrors under different conditions. However, proper and effective selection of mirror raw materials can obtain the most economically developed service life and the best characteristics.
The medium is water, liquefied gas and other non corrosive. Under normal temperature and working pressure, the pipeline made of gray cast iron can be used.

WC alloy steel can be used for saturated steam, saturated steam, high and ultra-low temperature product oil, vaporized steam, air compression, water, gas, etc. when the application temperature is less than 200 ℃ and the application working pressure is less than 1.5MPa.
1. Monel alloy can be used in the pipeline with hydrochloric acid medium.
2. Martensitic stainless steel plate can be used for pipeline with general corrosive medium.
3. Hastelloy or titanium alloy can be used in pipelines with strong corrosive medium such as dilute sulfuric acid.
Alloy copper can be used in oxygen pipeline and offshore pipeline.

In the pipeline with strong corrosion, when the working pressure is not higher than 1.0MPa and the application temperature is not higher than 50 ℃, the non-metallic materials such as rubber lined pipeline, fluorine lined pipeline and FRP anti-corrosion can be used. The greater characteristic of non-metallic pipeline mirror is its strong corrosion resistance, and even has the advantage that metal composite materials can’t have.
common problem:

STV Valve Technology . proposes that when the application temperature of the pipe mirror is higher than 200 ℃, the glass window must be made of quartz glass, and the strongly corrosive pipe window must be made of tempered borosilicate glass.

​We’ve been in business for more than a 20 years, and over the years, we’ve learned what makes a good product. Dependability, durability and affordability are among our top considerations. If we don’t have a valve that meets your needs, we can even create a custom-made valve for your project. Reach out today for more information on our process and product options.

5 Tips For Selecting The Industrial Valve

/in /by

There are many types of industrial valves. When customers choose valves, they usually choose them according to the operating temperature, ambient temperature, pipe diameter, pipe pressure, operating pressure, interface size, medium flow, medium name, etc

Valves are part of the everyday life. They are used in many industrial, commercial and residential places to make a machine or a system work out. They are used in plumbing systems, safety devices, and many others that are used every day. A valve is anything that controls the flow of liquids, liquidized solids, gases, slurries and other by permitting them to pass through, obstructing the passages, or partially just doing so. Here are some tips on choosing an industrial valve:

Tip 1: Industrial valves come in many shapes and sizes, and choosing the best one depends on the things it would control. What would be the matter your system would regulate? Is it a gas or a liquid? Is it corrosive or not? Leaking would be minimized and large losses would be avoidable. Viscosity plays a big role on the selection of the valves you should use. If you use a valve that cannot handle viscous matter, leakages are most likely to happen. High-pressure gases would be difficult to seal. Furthermore, there are also some gases like methane and hydrogen that could ignite at the slightest exposure to other gases and liquids.

Tip 2: You should also consider the temperature of the matter that would pass through the passageways of your system. There are gases and liquids that expand or contract in varying temperatures, and the knowledge of these facts and numbers would be beneficial to one when choosing an industrial valve. Knowing how much a matter expand or contract in a lower or higher temperature is always a good thing.

Tip 3: As already said, the pressure is something to consider. It is hard to seal a gas or liquid that has high pressure. 70.0 bars would produce leakages 10 times more than systems that are operating on the same valve with 7.0 bars.

Tip 4: An excellent valve would only remain excellent for some years. Whether you don’t or you do know how to maintain industrial valves, they could only give you excellent performance some time and would then slowly retire. You might notice some minute leakages at first, but maintenance of these valves should include having someone to check every day or every week for some leakages. Dangerous systems would need checking and maintenance of the whole system more frequently, and this holds true for the checking and maintenance of an industrial valve.

Tip 5: It is also best to choose a valve that is right for you and anyone else in the industry. To do this, you should choose a valve that has been approved and certified, and meets the current standard codes. You should also check that the supplier of the valve is a pleasure to make business with, or risk having your supplies delayed and your customers angered.

The selection of industrial valves is one of the most important decisions you have to make in the process of the creation, maintenance and repair of a system. In order to have a perfectly working system, you need to have the components perfect, or the overall quality of the system would be compromised.

How do I choose a valve?
Determine the pressure and temperature requirements. Find out both the temperature and pressure ranges where the valve will be installed. Metal valves tend to withstand higher temperatures and pressures than plastic valves. Metal valves are also usually best for pressurized gases.
What is the main purpose of choosing the right type of valve to be used in process control?
Control valves alter fluid flow by varying the size of the flow passage as directed by a signal from a controller. This enables the direct control of flow rate and the consequential control of key process parameters, including pressure, temperature and liquid level.

Overview of industrial valves

/in /by

Industrial valve is an important accessory to control the flow of medium in industrial pipeline. It can be used to control the flow of air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. The valve is composed of valve body, opening and closing mechanism and valve cover

What are you looking for in an industrial valve? What are the best things to consider when choosing one? Because an industrial valve is important and is a part of many different things in many different industries, there is a great demand for honest and truthful industrial valve reviews. The question is what reviews should you believe in and what reviews should you be skeptical about? Here are some tips and reviews to help you choose:

The Basic Valves

Stop and check valves are the basic types of valves. Of course there are many different and more complicated types of valve, but stop and check valves are the foundations of these valves. Unlike other valves which depend on the flow or action of the substances it contains, a stop valve is basically a valve that could be opened or closed at will. Manually, it could be switched to prevent or promote flow of liquids, gases and other substances. A check valve, also more commonly known as a one-way valve, is a two-port valve that permits entry to one and permits exit to another.

The More Complicated Valves

Of course, one wouldn’t be able to compress and classify all types of valves into stops and checks. There are more complicated industrial valves out there and they are very much helpful in many industries.

  • Balls, plugs and butterfly valves are valves which has movable flows.  Ball valves have ball-shaped disks with holes, which when rotated would close or open the valve. Plugs are cylinders with holes and these also make use of holes moved perpendicular to the flow to close them. Butterfly valves are used to isolate or regulate flow; they are more similar to ball valves but are cheaper and lighter.
  • Gate and globe valves are also more common types of valves. Also known as a sluice valve, a gate valve would either fully close or fully open. There are no partials here, as the flow of the matter would require that you fully lift up a rectangular or circular wedge out of the way. Even at higher pressures, a gate valve would remain tightly shut. Globe valves are one of the most efficient types of valves. They are one of those valves which would always experience lesser leakages and lesser losses.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The Reviews

Of course, manufacturer reviews would always be good. If you see a manufacturer that tells you everything about the product – strengths and weaknesses alike – you have found an honest manufacturer. If you want to find the best reviews for industrial valves, it is best to look in third-party sites that do not get paid to publish good reviews for a product. Being skeptical is human nature, but trusting an honest review is a very good way to find the best things in the world. You might want to check for any inconsistencies about the review too. There is no perfect product but there could be the best product for you and your system.

 

API 594 Face to Face Dimensions Dual-Plate Wafer Check Valves

/in /by

Face to Face Dimensions Dual-Plate Wafer Check Valves API Std. 594 Class 150-2500 Type A

Dual-Plate Wafer Check Valves

NPS CLASS
150 300 600 900 1500 2500
2 60 60 60 70 70 70
2½ 67 67 67 83 83 83
3 73 73 73 83 83 86
4 73 73 79 102 102 105
6 98 98 136 159 159 159
8 127 127 165 206 206 206
10 146 146 213 241 248 254
12 181 181 229 292 305 305
14 184 222 273 356 356
16 191 232 305 384 384
18 203 264 362 451 468
20 219 292 368 451 533
24 222 318 438 495 559
30 305 368 505
36 368 483 635
42 432 568 701
48 524 629
NPS 150 300 600 900 1500 2500
CLASS

Notes:

  • Dimensions are in millimeters unless otherwise indicated.
  • The face-to-face tolerance shall be as specified in ASME B16.10 for sizes
    through NPS 24 and shall be 3 mm for sizes larger than NPS 24.
  • Flange faces with ring-joint grooves shall conform to the dimensions
    shown in either ASME B16.5 or ASME B16.47, as applicable.

what is the different Difference between ball valve and globe valve

/in /by

There are many different types of valves for different applications, so how do you know which is the best to use for your application?  Let’s look at globe valves and ball valves.  The main difference between these two types is the way they close.  A globe valve uses a plug (stem) that closes against the flow, and a ball valve has a gate (ball) that closes across the flow.  Globe valves are good for regulating flow, whereas ball valves are better for on/off control without pressure drop.

For decades globe valves were considered the industry standard in control valves.  They are designed with a stem that moves up and down inside the valve to control flow.  They are commonly used on hot and chill water coils, and larger models are often used to control flow to chillers.  One of the main limitations of globe valves is that their close-off rating can be lower than other valves, especially in the larger sizes.

Ball valves are designed with a ball inside the valve.  The ball has a hole through the middle so that when the hole is in line with both ends of the valve, flow will occur.  When the valve is closed by turning the ball 90 degrees, the hole is perpendicular to the ends of the valve, and therefore flow is blocked.  Ball valves are very durable and usually have excellent shutoff even after years of use.  They are generally preferred over globe valves in shutoff applications.  The main limitation for ball valves is proportional control because of the large amount of flow that the ball allows.

 

 

 

 

 

 

 

 

 

 

 

The key difference between a globe and a ball valve is that a ball valve is designed, mainly, for shut-off operations, whereas a globe valve is designed, mainly, to throttle fluids. These two valves are industry-standards respectively for shut-off (ball valve) and for regulation (globe valve) applications.

A globe valve does not fit shut-off operations, due to the pressure drop it creates in the piping system (a problem that does not exist for full bore ball valves).

Ball valves have a long service life even in case of continuous on-off operations; globe valves would deteriorate easily under this type of service.

 

[nolink]