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Differences Between a Ball Valve & a Butterfly Valve

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Everyone knows that there are many types of ball valves, including this butterfly valve. Then the well-known difference between a ball valve and a butterfly valve is its opening and closing member. The opening and closing member of the butterfly valve is a block plate, and the ball valve is a ball. They all rotate around one axis of their own. Let’s continue to see what is the difference between a butterfly valve and a ball valve.

Comparison between butterfly valve and ball valve
Advantages of butterfly valve 1: simple structure, small volume and light weight; disadvantages are that the range of using pressure and working temperature is much smaller than that of ball valve
Advantages of butterfly valve 2: good sealing can be realized under low pressure; the disadvantage is that the sealing performance is much worse than that of ball valve
Advantages of butterfly valve 3: it can transport mud with the least liquid accumulated in the pipe mouth, which is better than the ball valve
Advantages of butterfly valve 4: the structural principle of butterfly valve is more suitable for making large-diameter valve, widely used in oil, gas, chemical industry and other industries

Difference one
The cut-off method of ball valve and butterfly valve is different: the ball valve blocks the passage through the ball to realize the pipe cut-off flow; the butterfly valve relies on the butterfly wing, so the pipe will not flow if it is spread and sealed.

Difference two
The structure of the ball valve is different from that of the butterfly valve: the ball valve is composed of the valve body, valve core and valve rod assembly, and the body can only see some parts; the butterfly valve is composed of the valve body, valve seat, valve plate and valve rod, and all the accessories are exposed outside. Therefore, the tightness of butterfly valve is not as good as that of ball valve. When it comes to sealing, butterfly valves are also divided into soft sealing and hard sealing. Butterfly valve structure is relatively simple, can only be used in low-pressure environment, the highest pressure is only 64 kg. Compared with the ball valve, the maximum ball valve can reach about 100 kg.
Difference three

 

The working principle of the ball valve and butterfly valve is different: the ball valve has a 90 degree rotation action, only because its opening and closing parts are a ball, only need to operate 90 degree rotation to achieve opening or closing, which is most suitable for switching. But now v-ball valve can be used to regulate or control the flow. Butterfly valve is a kind of valve that uses disc type opening and closing parts to turn back and forth about 90 ° to open, close or regulate medium flow. It has a good function of regulating flow and is one of the fastest-growing valve varieties.

 

 

 

 

 

 

 

FAQ

What is a butterfly valve used for?
Butterfly valves are used where space is limited. Unlike gate valves, butterfly valves can be used for throttling or regulating flow as well as in the full open and fully closed position. The pressure loss through a butterfly valve is small in comparison with the gate valve
What is difference between ball valve and globe valve?
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.
Why are ball valves so expensive?
This is due to the fast opening/closing of the ball valve that may cause a water hammer. Cost: A ball valve is generally more expensive than a gate valve of the same specifications. However, a ball valve is typically more durable and requires less maintenance compared to a gate valve.

Why are forged steel valves black?

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Not all forged steel valves are black, such as stainless steel forged steel valves will not be black. You may refer to a forged steel valve made of A105 material, which is phosphatized and blackened for rust prevention. Generally, the forged steel valve of A105 material is generally phosphating black.

 

What is the torque of the hard seal ball valve?

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Hard-sealed ball valves are also a type of wear-resistant ball valves. Today we will talk about the calculation of the torque of hard-sealed ball valves. The torque of the hard-sealed ball valve is also smaller than that of a soft seal such as F4 (fluoroplastic). Generally, the torque of a metal hard-sealed ball valve is more than twice that of a soft seal. And if it is designed or used improperly, it will be stuck. The advantage of a hard-sealed ball valve over a soft-sealed ball valve is that it can be used at high temperatures or where wear is required.

The pressure hard seal ball valve is under load. The higher the pressure, the larger the load and the more laborious the operation, that is, the greater the operating torque. Factors affecting the torque of the hard-sealed ball valve are the pressure (load), the friction of the moving pair, the packing friction of the bonnet stuffing box, the machining accuracy of the rotating parts, the degree of lubrication, the pre-tightening force of the threaded joint, and the valve stem. Deformation, because the frictional force of the partial area between the valve stem and the cover rises linearly, the operating torque will increase sharply, and even the valve stem can not move directly. If the pneumatic actuator and the electric actuator do not have measures to deal with the fault, it is easy to cause Pneumatic actuators and electric actuators are damaged.

The torque calculation of the valve is specifically: the square of the valve diameter of the one-half of the valve is 3.14, which is the area of ​​the valve plate, and multiplied by the pressure (ie the working pressure of the valve) to obtain the static pressure of the shaft, multiplied by the friction coefficient. (To check the table, the friction coefficient of general steel is 0.1, the friction coefficient of steel to rubber is 0.15), multiplied by the shaft diameter divided by 1000 to obtain the torque of the valve, the unit is cattle·meter. STV valve engineers recommend that the driving torque of the floating ball valve and the fixed ball valve drive device is at least 1.3 times the operating torque of the valve. The operating torque of the metal hard seal floating ball valve is about 4 times that of the soft seal floating ball valve. The metal hard seal is fixed. The operating torque of the ball valve is approximately 3-4 times the operating torque of the soft seal fixed ball valve.

F91 Pressure forged steel self-sealing check valve

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The forged steel check valve is a pressure self-tightening valve cover. The valve designed according to this design form has a valve body and a valve cover which are screwed, and the internal pressure is sealed by a self-sealing ring. The optional sealing discs are available in swing type, lift type, and ball type. The connection standard can be American or GB threaded, welded and flanged.

What is the function of the foot valve?

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The Foot valve consists of valve evaluation, disc, bonnet, bushing, sealing ring and other parts. See the water from the water source in the figure below from the bonnet to the valve body. Under the action of fluid pressure, the valve disc opens water.

When the pressure in the outlet pipe closes the valve disc rapidly after stop, the liquid will not be poured back to the water source, which plays the role of unblocked pumping and saving water energy loss.

  1. Check valves should be installed on equipment, installations and pipes to prevent medium backflow.
  2. Check valves are generally suitable for cleaning media, not for media containing solid particles and high viscosity.
  3. Vertical lift check valves should be generally used in horizontal pipelines with nominal diameter of 50mm.

what a wafer ball valve

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Wafer ball valve is Introducing a new type of thin-type ball valve that has been developed after absorbing foreign advanced production technology

The wafer ball valve is simple in structure, small in size and light in weight, and consists of only a few parts. Moreover, it can be quickly opened and closed by only rotating 90°, and the operation is simple, and the valve has good fluid control characteristics. When the ball valve is in the fully open position, the thickness of the valve plate is the resistance of the medium flowing through the valve body, so the pressure drop generated by the valve is small, so that the flow control characteristic is good. The tower valve has two sealing types: a spring seal and a metal seal. Elastomeric sealing valve, the sealing ring can be mounted on the valve body or attached to the periphery of the valve plate.

The wafer ball valve is also widely used in chemical, petrochemical, smelting, medicine, food and other industries in SO2, steam, air, gas, ammonia, CO2 gas, oil, water, brine, lye, seawater, nitric acid, hydrochloric acid, Use as a regulating and shut-off device in the pipeline of medium such as sulfuric acid or phosphoric acid

STV Delivery Forged Steel Wafer Ball Valve,150LB,F316L,DN50

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Product Name: Forged Steel Wafer Ball Valve,150LB,F316L
Connect form: flange.
Size: 1/2″ – 4″.
Suitable medium: water, oil, steam,
Suitable temperature: -40 – +150°C.
Working pressure: 1.6 -2.4 – 6.4.
Main material: A105.F304 ,F316,F316L.
Design and manufacture adoption: ISO, API, GB, BS, we are strict with the security
and quality ,it was accepted by clients and sells to internal, external market.

STV Valve Technology Group Co., Ltd is a professional leader China wafer ball valve,wafer ball valve stainless steel,wafer type ball valve,wafer ball valve manufacturers,lug wafer ball valve,wafer ball valve dimensions,wafer ball valve face to face,wafer ball valve italy,wafer ball valve pn16,wafer flanged ball valve,wafer floating ball valve,wafer pattern ball valve,wafer type ball valve drawing,wafer type ball valve manufacturers manufacturer with high quality and competitive price.

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How to choose the stainless steel valve

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  1. Care must be taken when selecting a suitable stainless steel valve. In order to avoid ambiguity, you should have an understanding of stainless steel valves;
         2, the requirements of the characteristics need to look at the flow resistance, discharge capacity, flow characteristics, sealing level and other information is how;
         3. For the reliability and service life of the product, it is necessary to ask in detail;
         4. If the chemical composition of the stainless steel valve does not meet the corresponding national standards, it does not need to be purchased and selected;
         5. Because stainless steel valves are manual, electric, pneumatic, etc., it is necessary to clarify how the operation mode is;
         6, when buying, you must choose a good after-sales service

Stainless steel valves are widely used in pipeline installations in petroleum, chemical, metallurgy, textile, food, shipbuilding, medical, environmental protection and other industrial sectors. They have the ability to resist atmospheric oxidation, ie, rust, and also contain acid. The ability of the alkali, salt medium to resist corrosion, that is, corrosion resistance.

STV Valve Technology Group Co., Ltd offers a wide range of stainless steel ball valve,stainless steel gate valve,stainless steel globe valve,stainless steel check valve,stainless steel foot valve .

What is the Working principle and characteristics of stainless steel 3-way ball valve

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Stainless steel 3-way ball valve anti-corrosion, anti-penetration, anti-friction multi-layer seal, valve seat with soft and hard double seal, increase the stability of the seal, valve body material: carbon steel, stainless steel, working temperature: -46 ° C ~ +200 ° C

Stainless steel 3-way ball valve is a relatively new type of ball valve, it has its own unique structure of some advantages.Stainless steel three-way ball valve has the advantages of small fluid resistance, simple structure, small volume, light weight, compact and Reliable, convenient operation, quick opening and closing, convenient maintenance and so on. The following details of the stainless steel tee ball valve working principle and stainless steel tee ball valve advantages.

It works as follows:
A, the opening process
1 In the closed position, the ball is mechanically pressed by the valve stem and pressed against the valve seat.
2 When the handwheel is turned counterclockwise, the valve stem moves in the opposite direction, and the bottom angular plane causes the ball to disengage from the valve seat.
3 The valve stem continues to lift and interacts with the guide pins in the spiral groove of the valve stem, causing the ball to start rotating without friction.
4 Until the fully open position, the stem is raised to the extreme position and the ball is rotated to the fully open position.
B, the closing process
1 When closing, turn the handwheel clockwise, the valve stem begins to lower and the ball moves away from the seat.
2 Continue to rotate the hand wheel. The valve stem is subjected to the guide pin embedded in the upper spiral groove, so that the valve stem and the ball rotate at 90° at the same time.
3 When it is about to close, the ball has rotated 90° without contact with the seat.
4 In the last few turns of the handwheel, the angular plane at the bottom of the valve stem mechanically wedges against the ball, causing it to press tightly against the valve seat for a complete seal.
Five, stainless steel three-way ball valve structure features:

  1. Open and close without friction. This function completely solves the problem that the conventional valve affects the sealing due to the friction between the sealing faces.
  2. Top-loading structure. The valve installed on the pipeline can be directly inspected and repaired online, which can effectively reduce the parking of the device and reduce the cost. This type of valve should generally be installed horizontally in the pipeline.
    3, single seat design. It eliminates the problem that the cavity medium in the valve affects the safety of use due to abnormal boosting.
  3. Low torque design. The specially designed valve stem can be easily opened and closed with a small handle.
  4. Wedge seal structure. The valve is mechanically supported by the valve stem, and the ball wedge is pressed onto the valve seat to seal, so that the sealing property of the valve is not affected by the change of the pressure difference of the pipeline, and the sealing performance is reliably guaranteed under various working conditions.
  5. Self-cleaning structure of the sealing surface. When the ball is tilted away from the valve seat, the fluid in the pipeline passes through the spherical sealing surface at 360°, which not only eliminates the high-speed fluid scouring on the valve seat, but also washes away the accumulation on the sealing surface to achieve self-cleaning.

STV Valve Technology Group Co., Ltd is a professional leader China  stainless steel 3-way ball valve Manufacture,stainless steel 3 way ball valve,high pressure stainless steel 3 way ball valve,1 stainless steel 3 way ball valve,1/2 stainless steel 3 way ball valve,1/4 3 way stainless steel ball valve,3 way actuated ball valve stainless steel,3 way flanged ball valve stainless steel.

How to Identification of BSPP,BSPT, NPT threads?

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When you choose valves and pipe fittings, thread is a very important feature you have to consider. No matter how well the product is made, a wrong thread type will make it useless. You have to determine the thread type before you order.

NPT Connections
NPT (National Pipe Thread) seals are the most popular type of seal for pressure calibration systems in the U.S. and Canada. NPT male adapters have a taper thread that wedges into the female NPT adapter. They seal due to the “out of roundness principle” which means that the male stretches the female fitting until there is so much force that the connection can hold pressure. One of the challenges with this design is that if you connect stainless steel to stainless steel then over-tightening or poor lubrication can cause gauling and damage to the threads. Thread sealant is needed to seal but only 2 turns of thread sealant is required. Any more than that and the seal can leak around the thread sealant. Ralston Instruments has a wide variety of male NPT adapters , male Quick-disconnect NPT adapters, male NPT calibrator adapters, female NPT adapters, female NPT gauge adapters and female Quick-disconnect NPT gauge adapters.

BSPT Connections

BSPT (British Standard Pipe Thread) is similar to NPT except there are important differences. The angle across the flanks of threads (if you sliced the fitting in half long-ways and measured the angle from root to crest to root) is 55 degrees instead of 60 degrees as it is for NPT. Another important difference is that for many BSPT pipe sizes the thread pitch is different than NPT. Thus an NPT male will sometimes fit into a BSPT fitting or vice versa but they will not seal. This is a popular fitting in China and Japan but is very rarely used in North America unless the equipment to which it is attached was imported. Thread sealant is needed to seal the male and female fitting together. Ralston Instruments has adapters to both male BSPT adapters and female BSPT adapters.

BSPP Connections
BSPP (British Standard Parallel Pipe) is most popular in the UK, Europe, Asia, Australia, New Zealand and South Africa. It is a parallel thread fitting that uses a bonded seal ring to do the sealing. This bonded ring seal is sandwiched in-between a shoulder on the male fitting and the face of the female fitting and is squeezed in place. BSPP pressure gauges have a longer male thread and use a copper crush washer that is squeezed in between the bottom of the male fitting and the bottom of the female BSPP hole forming a pressure tight seal. No thread sealant is needed to form a seal. Ralston Instruments has male BSPP adapters , female BSPP adapters, female BSPP gauge adapters, and female BSPP Quick-disconnect gauge adapters.

our company has mainly produces and sells : stainless steel threaded fittings , BSPP ball valves ,NPT threaded valves ,quick , welding pipe fittings ,pneumatic valves ,etc

How do you identify BSP and NPT threads?
 
With NPT, the peaks and valleys of the threads are flat. In BSP, they are rounded. Secondly, the NPT angle of the thread is 60 degrees and the BSP angle is 55 degrees.
 
How do I know what BSPP fittings I have?
 
To identify a BSPP fitting complete the following steps:
  1. Confirm the thread is parallel or tapered.
  2. Determine the threads per inch (TPI) count using a thread gauge or calipers.
  3. Determine the thread O.D (male thread) or I.D (female thread) using calipers.
How can I tell what NPT threads I have?
 
As a general “rule of thumb” an NPT thread is approximately 1/4″ (0.25”) larger than its “name.” For a 1/4″ NPT fitting the “nominal” OD is 0.533”. NPT fittings are slightly tapered so the “nominal” diameter is the diameter in the middle of the threaded portion, as measured by the top (crest) of the threads.
 
What are the three basic types of threads?
 
Three are parallel (UN/UNF, BSPP, metric parallel) and three are tapered (NPT/NPTF, BSPT, metric tapered). Three are pipe threads (NPT/NPTF, BSPT, BSPP) and three are not (UN/UNF, metric parallel, metric tapered).