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Comparison of the characteristics of wafer butterfly valves and flanged butterfly valves

To find out what is the difference between the wafer butterfly valve and the flange butterfly valve, let’s take a look at the comparison of some characteristics of the wafer butterfly valve and the flange butterfly valve.

Wafer type butterfly valve with worm gear

Wafer type butterfly valve with worm gear

The biggest difference is of course that the flanged butterfly valve has two more flanges, and the wafer type has two fewer flanges. Of course, the price is cheaper, and the price is about 2/3 of the flange. Flange butterfly valves are more reliable than wafer butterfly valves. Wafer butterfly valves are not as convenient as flanged butterfly valves in installation, because they need to be equipped with flanges, which can easily leak if they are not installed well.

From the perspective of specific working conditions, when selecting imported valves, use wafer-type butterfly valves as much as possible, which are light in weight and easy to replace. However, the length of the bolts of the wafer butterfly valve is longer, and the construction accuracy is higher. If the flanges on both sides are not aligned, the bolts will be subjected to greater pressure and the valve is prone to leakage. Under high temperature conditions, the bolts of the wafer butterfly valve may cause leakage after expansion, so if it is under high temperature conditions, the wafer butterfly valve is not suitable for large pipe diameters. In addition, wafer butterfly valves generally cannot be used at the end of the pipeline and downstream where it needs to be disassembled, because when the downstream flange is disassembled, the wafer valve will fall off. In this case, a short section must be made separately. For disassembly. The wafer butterfly valve has no flanges at both ends of the valve body, only a few guide bolt holes, and the valve is

Double flange butterfly valve (17)

Double flange butterfly valve (17)

connected with the flanges at both ends by a set of bolts/nuts. Compared with flanged butterfly valves, it is easier to disassemble. The cost of the valve is lower, but the disadvantage is that one sealing surface has a problem, and both sealing surfaces have to be disassembled. Regarding the blue butterfly valve, the above problem does not exist, and of course it has to pay a higher cost. But the cost will be higher.

The flange type butterfly valve has flanges at both ends of the valve body, which are connected with pipe flanges. The seal is relatively more reliable.
In addition to selecting the appropriate wafer butterfly valve or flange butterfly valve, attention should also be paid to the installation and maintenance of the butterfly valve. Because this is actually a place that can affect the selection of the valve outside of the specific purpose. Let’s take a look at the specific requirements below:
1. The valve disc stops at the closed position during installation.
2. Determine the opening position according to the rotation angle of the butterfly plate.
3. For the butterfly valve with bypass valve, the bypass valve should be opened before opening.
4. Ask professionals to install according to the manufacturer’s instructions, especially the heavy butterfly valve should be fixed.
5. The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical passage of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0° and 90°. When rotated to 90°, the butterfly valve is fully open.
The butterfly valve is used as a flow control, the main thing is to choose the size and type of the valve when purchasing. Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, and water treatment, but also used in cooling water systems of thermal power stations.

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

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Daily maintenance and precautions of ball valves
What is a wafer type butterfly valve
electric wafer butterfly valve vs electric flange butterfly valve
Wafer type double disc swing check valve introduction

Comparison table of valve diameter and medium flow rate

It is well known that the flow rate and flow rate of the valve mainly depend on the diameter of the valve, and also

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

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

related to the resistance of the valve structure to the medium. At the same time, it has a certain internal connection with various factors such as the valve pressure, temperature and medium concentration. The flow channel area of ​​the valve has a direct relationship with the flow rate and flow rate, and the flow rate and flow rate are two mutually dependent quantities. When the flow rate is constant, the flow rate is large, the flow channel area can be smaller; the flow rate is small, the flow channel area can be larger. On the contrary, the flow channel area is large, its flow velocity is small; the flow channel area is small, its flow velocity is large.
1. The flow rate of the medium is large, and the valve diameter can be smaller, but the resistance loss is large and the valve is easily damaged. If the flow velocity is large, it will have electrostatic effect on flammable and explosive media, causing danger; the flow velocity is too small, the efficiency is low and it is not economical. For the medium with high viscosity and explosive, the flow rate should be smaller. The flow rate of oil and liquid with high viscosity is selected according to the viscosity, generally 0.1~2m/s.
2. In general, the flow rate is known, and the flow rate can be determined by experience. The nominal diameter of the valve can be calculated through the flow rate and flow rate.
3. The valve diameter is the same, its structure type is different, and the fluid resistance is also different. Under the same conditions, the larger the resistance coefficient of the valve, the more the flow rate and flow rate of the fluid through the valve will drop; the smaller the valve resistance coefficient, the less the flow rate and flow rate of the fluid through the valve will drop.
The common flow rates of various media are shown in the following table:

liquid type use condition speed m/s
satuated vapor DN>200 30-40
DN=200-100 25-35
DN<100 15-30
superheated steam DN>200 40-60
DN=200-100 30-50
DN<100 20-40
low pressure steam P<1.0 (absolute pressure) 15-20
midium pressure steam P=1.0-4.0 (absolute pressure) 20-40
high pressure steam P=4.0-12.0 (absolute pressure) 40-60
compressed air vaccum 5-10
P≤0.3 (instrument pressure) 8-12
P=0.3-0.6 (instrument pressure) 10-20
P=0.6-1.0 (instrument pressure) 10-15
P=1.0-2.- (instrument pressure) 8-12
P=2.0-3.0 (instrument pressure) 3-6
P=3.0-30.0 (instrument pressure) 0.5-3
Oxygen P=0-0.05 (instrument pressure) 5-10
P=0.05-0.6 (instrument pressure) 7-8
P=0.6-1.0 (instrument pressure) 4-6
P=1.0-2.0 (instrument pressure) 4-5
P=2.0-3.0 (instrument pressure) 3-4
gas 2.5-15
semi-water gas P=0.1-0.15 (instrument pressure) 10-15
natural gas 30
Nitrogen P=5.0-10.0 (absolute pressure) 15-25
Ammonia vaccum 15-25
P<0.3 (instrument pressure) 8-15
P<0.6 (instrument pressure) 10-20
P≤2 (instrument pressure) 3-8
Acetylene water 30
5-6
Acetylene gas P<0.01 (instrument pressure) 3-4
P<0.15 (instrument pressure) 4-8
P<0.25 (instrument pressure) 5
chlorine  gas 10-25
liquid 1.6
Hydrogen chloride  gas 20
liquid 1.5
liquid ammonia vaccum 0.05-0.3
P≤0.6 (instrument pressure) 0.3-0.8
P≤2.0 (instrument pressure) 0.8-1.5
Sodium hydroxide concentration 0-30% 2
concentration 30-50% 1.5
concentration 50-73% 1.2
Sulfuric acid concentration 88-93% 1.2
concentration 93-100% 1.2
hydrochloric acid 1.5
water and other similar viscosity liquid P=0.1-0.3 (instrument pressure) 0.5-2
P≤1.0 (instrument pressure) 0.5-3
P≤8.0 (instrument pressure) 2-3
P≤20-30 (instrument pressure) 2-3.5
Heating network circulating water Cooling water 0.3-1
pressure backwater 0.5-2
pressureless backwater 0.5-1.2
tap water main pipe P=0.3 (instrument pressure) 1.5-3.5
sub pipe P=0.3 (instrument pressure) 1-1.5
boiler feed water >3
steam condensate 0.5-1.5
condensate free flow 0.2-0.5
superheated water 2
seawater and brackish water P<0.6 (instrument pressure) 1.5-2.5

Note: The unit of DN value is mm; the unit of P value is MPa.
for example:
The resistance coefficient of the gate valve is small, only in the range of 0.1 to 1.5; the resistance coefficient of the large diameter gate valve is 0.2 to 0.5; the resistance coefficient of the narrow gate valve is larger.
The resistance coefficient of the stop valve is much larger than that of the gate valve, generally between 4 and 7.
The resistance coefficient of the Y-type globe valve (DC type) is small, between 1.5 and 2; the resistance coefficient of the forged steel globe valve is large, even as high as 8.
The resistance coefficient of the check valve depends on the structure: the swing check valve is usually about 0.8-2, among which the multi-leaf swing check valve has a large resistance coefficient; the lift check valve has a large resistance coefficient, up to 12 .
The resistance coefficient of the plug valve is small, usually about 0.4 to 1.2.
The resistance coefficient of the diaphragm valve is generally around 2.3.
The drag coefficient of butterfly valve is small, generally within 0.5. The resistance coefficient of the ball valve is small, generally around 0.1.
Note: The resistance coefficient of the above valve is the value when the valve is fully opened. The selection of valve diameter should take into account the machining accuracy and dimensional deviation of the valve, as well as other factors. The valve diameter should have a certain margin, generally 15%. In actual work, the valve diameter depends on the diameter of the process pipeline.

Related products: wafer butterfly valve; lug butterfly valve; double flange butterfly valve;
Double eccentric butterfly valve

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

Related news/knowledge:
Prevention and treatment of valve corrosion;
Valve flow characteristic curve and classification;
What is the gear modification coefficient;
Valve model establishment and meaning

Comparison of bellows globe valve and ordinary globe valve

Comparison of bellows globe valve and ordinary globe valve:

Globe valve (3)

Globe valve (3)

1. Double sealing design (bellows + packing) If the bellows fails, the stem packing will also avoid leakage and meet international sealing standards.
2. There is no fluid loss, reducing energy loss and improving plant equipment safety.
3. Long service life, reduce maintenance times and lower operating costs.
4. The sturdy and durable bellows seal design ensures zero leakage of the valve stem and provides maintenance-free conditions.
5. The gas medium valve seat adopts PTFE soft sealing material to improve the sealing performance of this valve.
6. High temperature resistance≤425℃The valve seat adopts conical hard seal. Achieve airtight performance and zero leakage.

Tianjin Tanghai Valve Manufacturing Co., Ltd. is one of the largest globe valve manufacturers in China, main products are butterfly valves, check valves, gate valves and globe valves. Key words: butterfly valve, lug type butterfly valve, wafer type butterfly valve, U-type butterfly valve, double flange butterfly valve, gate valves, check valves, globe valves, valve parts (Valve body, Valve disc, Valve shaft, Valve seat…)

Our products use advanced manufacturing technology, and strictly conform to API, DIN, BS, EN, ISO, GB and other international standards. The main products are butterfly valves, gate valves, check valves, globe valves, valve parts (Valve body, Valve disc, Valve shaft, Valve seat…), etc. Our products are widely used in various fields such as marine industry, shipbuilding, petrochemical, metallurgy, water treatment, fire fighting, water supply and drainage, etc. The company has won unanimous recognition and praise from customers with high quality and good reputation.

Comparison and analysis of the performance of the wafer butterfly valve

With the same nominal pressure and nominal diameter, ordinary which has better tightness and is not easy to leak? butterfly valve or gate valve?

wafer type butterfly valve, NBR seat (11)

wafer type butterfly valve, NBR seat (11)

The airtightness of the gate valve is better than that of the butterfly valve, but there are also manufacturers’ butterfly valves that have better airtightness.
The gate valve is large in size and takes up a lot of space.
The butterfly valve is small in size and takes up little space.

When selecting concretely, the temperature of the medium, the sealing of the valve and the packing should also be considered.
The specification stipulates that the butterfly valve with a nominal diameter greater than 50 is used.

Wafer butterfly valve is a national key new product. The high-performance manual butterfly valve adopts a double eccentric and a special oblique cone oval sealing structure. It solves the shortcoming of the traditional eccentric butterfly valve that the sealing surface is still in sliding contact friction at the moment of opening and closing 0°~10°, and the sealing surface of the butterfly plate is separated at the moment of opening, and the effect of sealing when the contact is closed is achieved to extend the service life and maximize the sealing performance.

Tanghai Valve is the best manufacturer of wafer-type butterfly valve in China. We produce the best quality products with competitive low prices.

13 gate-valve-5

13 gate-valve-5

Our products use advanced manufacturing technology, and strictly conform to API, DIN, BS, EN, GB and other international standards. The main products are butterfly valves, gate valves, check valves, globe valves, valve parts (Valve body, Valve disc, Valve shaft, Valve seat…), etc. Our products are widely used in various fields such as marine industry, shipbuilding, petrochemical, metallurgy, water treatment, fire fighting, water supply and drainage, etc. The company has won unanimous recognition and praise from customers with high quality and good reputation.

We have established long-term and stable business relationships with many multinational companies. Our products are exported to Europe, the United States, Australia, and the Middle East, Southeast Asia and other countries and regions. The quality of our products has been widely recognized by customers, and has been trusted and praised by customers. Gradually we have established a close technical partnership with customers from various countries.

We are committed to “Build a top valve enterprise; Be a reliable partner!”

Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

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

related news /knowledge: What is a wafer type butterfly valve; Wafer butterfly valve installation instructions and steps;