Butterfly Valve

The butterfly valve is also called butterfly valve, as the name suggests, its key parts like a butterfly against the wind, free rotation. The butterfly valve disc is the disc, around the seat of a shaft rotation, the size of the angle of rotation is the valve open and close.

1.Butterfly valve construction

The butterfly valve is mainly composed of the valve body, living body, valve shaft, bearing, sealing device, operating mechanism, and accessories.

2.How butterfly valves work

The butterfly valve is according to rotate the valve stem drive disc rotating at the same time for opening and closing of a valve, cylindrical channels in the butterfly valve body, disc around the axis of rotation, mainly is 90 ° rotating disc for flow control, when the butterfly plate reaches 90 ° valves in the fully open position, at the same time can change the angle of the butterfly plate to adjust the medium flow rate, generally installed on the diameter of the pipe direction. Butterfly valve and stem themselves are not capable of locking, in order to effectively regulate the flow need to install worm gear reducer, the butterfly valve equipped with worm gear reducer not only makes the butterfly valve self-locking ability but also can change the operating performance of butterfly valve and more accurate regulation of medium flow.

1)Butterfly valve has small flow resistance when fully opened. When opened at about 15°-70°, and can be sensitive flow control, thus in the field of large-diameter regulation, the butterfly valve is a very common application. Most butterfly valves can be used in media with suspended solid particles because the disc movement is scrubbing. Depending on the strength of the seal, it can also be used for powder and granular media.

2)Butterfly valve is suitable for flow regulation. The butterfly valve in the pipe pressure loss is relatively large, about three times as much as the gate valve, so when choosing butterfly valve, the pipeline system should be fully considered by the impact of pressure loss, should also consider the butterfly plate under the pressure of the pipeline medium strength. In addition, consideration must be given to operating temperature limitations of resilient seat materials at high temperatures.

3)The structure length and overall height of the butterfly valve are small, opening and closing speed is fast, and has good fluid control characteristics. The butterfly valve structure principle is most suitable for the manufacture of large diameter valves. When butterfly valves are required for flow control, the most important thing is to correctly select the specifications and types of butterfly valves so that they can work properly and effectively.

3.History

Butterfly valves have been in use since the end of the 18th century. James Watt used a butterfly valve in his steam engine prototype. With advances in materials and technology, butterfly valves can be made smaller and can withstand higher temperatures. After World War II, synthetic rubber was used for seals, allowing butterfly valves to be used in more industries. In 1969, James E. Hemphill patented an improvement in the butterfly valve that reduced the hydrodynamic torque required to change the valve's output.

We are a Casting Valve Manufacturer. If you are interested in our products, please feel free to contact us.

Differences Between Cast Iron And Cast Steel

One of the most prominent ways to make enduring and also quality parts is with spreadings. Casting enables a high degree of information, which leads to not requiring as well as additional fabrication or setting up. While several products can be cast, steel and iron are both most popular as a result of their outstanding mechanical properties for a variety of applications.

Cast iron normally describes grey iron, pliable iron, and also malleable iron. Which is an iron casting with carbon web content of more than 2%.
Cast steel usually describes normal carbon steel and alloy steel. Which is steel spreading with carbon web content less than 2%.
For that reason, no big difference between the chemical content and also raw materials for cast iron vs cast steel.

Deterioration Resistance

When it involves corrosion, iron has better deterioration resistance than steel. That doesn't suggest that either is unsusceptible deterioration though. When left unprotected, both metals will oxidize in the existence of wetness. Eventually, they will completely decay. To prevent this, the coating is suggested for both steels as well as iron spreadings.

Expense

Cast iron is frequently less expensive than cast steel because of the reduced product costs, energy, and labor needed to create an end product. While raw steel is extra costly, there are, nonetheless, prefabricated kinds of steel. Those consist of sheets, poles, bars, tubes, and beams of lights.

Castability

Cast iron is fairly simple to cast, as it puts conveniently and does not diminish as much as steel. This flowability makes cast iron a suitable metal for architectural or ornate ironwork frameworks such as fencing and road furniture.

The advantage and disadvantage of cast iron

The grey cast iron's good casting residential properties are excellent vibration damping, good wear resistance, excellent machinability, and reduced notch level of sensitivity. However, its tensile toughness as well as prolongation are very low. So, it can just create some steel parts with reduced physical requirements. Needs such as safety cover, cover, oil pan, handwheels, framework, floor, hammer, small manage, base, frame, box, knife, bed, birthing seat, table, wheels, cover, pump, valve, pipeline, flywheel, electric motor blocks, etc. When it comes to greater qualities, grey actors iron can withstand better load and also a particular degree of rigidity or deterioration resistance. This permits a few of the more important spreadings such as a cylindrical tube, equipment, base, flywheels, bed, cylinder block, cylinder lining, piston, transmission, brake wheel, combining plate, medium pressure valve, and so on.

The ductile iron and malleable iron have high stamina, ductility as well as heat-resistance, and also strength. So a bigger application, sometimes, can replace carbon steel. However, its production innovation is high. The production process is a lot more complex. This makes the production expense higher than regular grey cast iron and also cast steel. Therefore, there are a lot more casting issues for pliable iron. There are numerous areas that make use of ductile iron, such as stress pipelines and also installations, automobile applications, farming, road and also building applications, and also general engineering applications.

The advantage and the disadvantage of cast steel

The major benefit of cast steel is layout versatility. The developer of the casting has the best liberty of layout choices. This permits intricate shapes as well as hollow cross-section components.
Cast steel has metallurgy manufacturing flexibility and also the toughest variability. One can choose various chemical structure and control that is adapted to the numerous needs of different projects. This provides various heat treatment choices in the larger context of the mechanical properties and also performance. Also using great weld-ability and also workability.
Cast steel is a type of isotropic material and also can be made into the general architectural strength steel spreadings. This improves the dependability of the task. Coupled with the layout and weight, the advantages of short delivery time, price, and also economic situation offers cast steel a competitive advantage.

The weight variety of steel castings is larger. Little weight can be only a few lots of grams of liquified mold accuracy spreadings. The weight of large steel castings rises to several tons, lots of lots, or numerous loads.
Steel castings can be used for a range of functioning problems. Its mechanical residential or commercial properties are superior to any other spreading alloys, and a variety of high-alloy steel for unique objectives. To endure high tensile tension or the vibrant load of parts, it is important to take into consideration pressure vessel castings. In low or high temperature, huge as well as fundamental part tons essential components ought to offer priority to steel castings.
However, cast steel has fairly negative shake-suction, use resistance, and mobility. The casting efficiency, contrasted to cast iron, misbehaves. Also, the costs are more than normal actors iron.
As a result, cast iron vs cast steel, have their very own benefits and downsides. Either should be chosen according to the application and also their physical residential or commercial properties.

The Distinction Between a Butterfly Valve As Well As Gate Valve

Two of one of the most popular valves on the market today are butterfly valves as well as gate valves, so let's explore what each type can do and what makes them such reliable devices.

Gate valves

As the name indicates, the main feature of a valve is as a gatekeeper. The gate is the main part of the gate valves. A movable gate within the valve allows circulation or blocks it. This movable gate is regulated by a mechanical aid such as a screw or lever, which lifts or reduces the gate within.
Gate valves have been available in several sizes and shape yet have a tendency to be huge. Think of the valves managing the flow of water in main water pipes. In spite of their sometimes vast size, gate valves are designed to be controlled by a single person.

Butterfly valve

A close relative of the gate valve, and also an innovative variation, a butterfly valve can also be available in many shapes and sizes. Such a shutoff also works by utilizing an internal entrance. The distinction between this as well as a gate valve is in the means eviction runs within the valve.
Unlike the gate valve, eviction within the butterfly valve remains set and swivels around an inner axis. The shape of the interior gateway swiveling is the beginning of the butterfly name.
The butterfly valve has the very same feature as eviction shutoff, which is permitting and also blocking the flow. There are, nonetheless, some benefits and disadvantages to both kinds of valves, and also it is necessary to maintain that in mind when picking either shutoff.

Advantages and also Drawbacks of Butterfly and Gate Valves

Pressure differential: gate valves are typically far better than butterfly shutoffs at executing under pressure. Their building and construction suggest that flow can keep going without producing any kind of unnecessary stress changes. And also their usage does not take much initiative.
This is not the situation for butterfly valves. Their swivel gateway building and construction indicate that the holding gate is subjected to greater levels of pressure differentials. This equates right to greater toughness required to run a butterfly valve. And this is frequently fixed by using a long arm to run larger butterfly valves.
Wear and tear: gate shutoffs often tend to outmatch the butterfly valve when it pertains to longevity. The actual style of the valve makes certain that it does not endure as high as a butterfly valve when functioning. Even though contemporary butterfly valves are generated with higher stress resistances in mind, the unfortunate fact is that its design ensures a higher price of wear. Whether the valve is being opened or shut, its seal is always in straight exposure to stream rate, unlike the gate valve. When turned on, parts of the gate shutoff are revealed to flow for really short ruptures of time.
Security: this depends on making use of the valve as well as the stress it might encounter. A knowledgeable designer that recognizes what these valves can as well as can not do can prevent this problem entirely. That being claimed, it is necessary to understand and also approve that butterfly valves weren't initially made to handle high-velocity circulation. Certainly 6 m/s is the best velocity recommended for this sort of valve. Anything above subjects the butterfly valve to dangerous stress differentials that can increase wear and tear as well as may bring about early failing and also crashes.
High-pressure decrease: an additional issue influencing butterfly valves is the decline of stress as it is released. Today's insistence on maintaining high pressure throughout a system to save power is one of the reasons that gate valves and other alternatives are coming back into fashion.
Price: butterfly valves tend to be cheaper than gateway valves.
Dimension: butterfly valves are smaller and a lot smaller. Usually, this allows them to be a lot more flexible in their use than gate valves.
Both valves are predestined to function as an avenue of flow and also not as a regulator. Neither is developed to be utilized continuously. Once they are released, the flow is uncontrolled.

Butterfly Valves: The Ultimate Guide

What is a Butterfly valve?

A butterfly valve is a quarter-turn valve that starts throttling as well as circulation control of fluids. Given its name, you can quickly picture a slim steel disc that "flutters" about a dealt with the axis (stem assembly). The opening and closing device permits and limits the flow of a medium between an upstream and also downstream pipeline.

What type of valve is a butterfly valve?

In a much more technological tone, a butterfly valve is a regulated rotating valve that includes a turning disk that directs the flow of fluid in a system. Basically, the disk is operable as much as 90 degrees and that's why it is called a quarter-turn valve. A butterfly valve regulates the flow linearly and also can be bi-directional. The setup, as well as the procedure of the valve, is similar to a ball valve, but it is lighter and also less expensive.
For strangling services, you can make use of a high-performance butterfly valve, which is a greater sector criterion for bigger applications. Normally, this kind of valve is made to process huge capacities and often, viscous and seawater tool. We will certainly obtain much more right into high-performance butterfly valves later.
You can locate butterfly valves usually in piping systems supplying big volumes of liquids. These valves are fragile and also not recommended to take care of completely dry mass solids as they can choke or break the butterfly valve.
The procedure can be through a packing from a pneumatic actuator, an electric motor, a solenoid, or a hydraulic piston and cylinder. Either way, this type of valve is the most economical and the easiest to handle. Butterfly Valves are also more affordable than other types of valves.

Advantages

Here are some of the advantages of butterfly valves compared with other valve types.
1.Lightweight and compact
2.Easy to install
3.Low-pressure loss
4.Low maintenance
5.Simple, rapid operation

Disadvantages

The disc can interrupt flow even when it is open
Not recommended for high differential pressures

What are Butterfly Valves used for?

Butterfly valves are used in many industrial applications such as:
HVAC
Vacuum service
High-temperature applications
Refrigeration and Air Conditioning systems

Irrigation and agricultural needs
Corrosive processing
Lubrication
Petroleum Industries
Wastewater treatment
Slurries
Sanitary valve applications
Sprinkler and fire protection systems
When it comes to choosing a butterfly valve type for a specific application, one can look into a pile of different valve classifications. Seat, body, and disc materials are varied depending on the service they will be used.

Regulating Fluid Flow

In butterfly valves, fluid flow constriction and control is easily done by just turning the valve handle. As it is a regulating valve, it controls the flow rate of the system through the help of actuators. Basically, when a flow monitor senses that a set parameter (differential pressure) has been reached, it will signal the valve actuator to close or open the valve.

To control a regulating valve remotely, it must have a flow controller that automatically communicates with the valve mechanism based on the flow rate.

Flow Isolation

Butterfly valves are used typically in low-pressure and low-temperature applications. They are lightweight and easy to manipulate and their quarter-turn action can also be used for flow isolation.

Backflow Prevention

In food industries where there are aggressive washdown processes, butterfly valves can be used for backflow prevention. This is necessary, from standard regulations, as it is aimed in food processing to deliver procedures in sanitary conditions.

Installation

Here are a few installation tips, as well as a checklist to take note of:
1.In order to check parts of the butterfly valve, you can be able to disassemble it in order to further inspect its parts.
2.Before anything, see to it that the flange and pipeline are clean from foreign materials. These can damage the seat or disc and can also cause the disc to movement restrictions.
3.Since resilient seated valves extend to both faces, gaskets are not needed.
4.In order to easily insert the valve body spread the flanges and align the pipe-work. With this, the valve body is inserted even with no contact to pipe flanges.
5.Partially open the valve disc to prevent the valve from jamming.
6.Insert the valve between the flanges, taking care not to damage the seat faces.
7.When you lift the valve, hold it by the locating holes. Also, you can tie up a nylon sling around the body or the neck. Make sure you do not lift the valve at the actuator or its operator.
8.Once the valve is placed and aligned in between the flanges, insert all the bolts before hand-tightening them.
9.Slowly open the disc. This will test if it has the right clearance from the inside of the pipes.
10.Afterwhich, a gradual closure of the valve should also be done to verify enough clearance from the disc to the pipe flanges.
11.Fully open the valve and start to tighten all of the bolts.
12.To test proper clearances after fastening the valve in the pipeline, repeatedly fully open and close the valve. This ensures the valve functions well during operation.

Precautions For Ball Valve Repair And Maintenance

The ball valve came out in the 1950s. With the rapid development of science and technology, the continuous improvement of production technology and product structure, in a short period of 50 years, it has rapidly developed into a major valve category. In the developed western countries, the use of ball valves is increasing year by year.

To make the ball valve have a longer service life and maintenance-free period, in addition to normal working conditions, maintaining a harmonious temperature/pressure ratio, and reasonable corrosion data, you will also rely on the following considerations:

When the Cast iron ball valve China is closed, there is still pressurized fluid inside the valve body.

Before repairing the ball valve, relieve the pipeline pressure, and keep the valve in the open position.

Before repairing the ball valve, disconnect the power or air source.

Before maintenance, separate the actuator from the bracket.

It is necessary to find out that the upstream and downstream pipelines of the ball valve have indeed relieved the pressure before disassembling.

During disassembly and reassembly, care must be taken to prevent damage to the sealing surface of parts, especially non-metal parts. Special tools should be used when removing O-rings.

When assembling the ball valve, the bolts on the flange must be tightened symmetrically, gradually, and evenly.

The cleaning agent should be compatible with rubber parts, plastic parts, metal parts, and working medium (such as gas) in the ball valve. When the working medium is gas, gasoline can be used to clean the metal parts. Clean nonmetal parts with pure water or alcohol.

The disassembled individual parts can be cleaned by dipping. Metal parts with non-metal parts that have not been decomposed can be scrubbed with a clean, fine silk cloth impregnated with a cleaning agent (to prevent fibers from falling off and adhering to the parts). When cleaning, all grease, dirt, glue, dust, etc. adhering to the wall must be removed.

Non-metal parts should be taken out of the cleaning agent immediately after cleaning, and should not be soaked for a long time.

After cleaning, it needs to be assembled after the cleaning agent on the wall surface to be washed evaporates (can be wiped with a silk cloth not soaked in cleaning agent), but it should not be left for a long time, otherwise, it will rust and be contaminated by dust.

New parts also need to be cleaned before assembly.

Use grease for lubrication. Grease should be compatible with ball valve metal materials, rubber parts, plastic parts, and working medium. When the working medium is gas, grease for lubrication can be used. Apply a thin layer of grease on the surface of the seal installation groove, apply a thin layer of grease on the rubber seal, and apply a thin layer of grease on the sealing surface and friction surface of the valve stem.

When assembling, it should not be allowed to pollute, adhere or stay on the surface of the parts or enter the cavity with metal chips, fibers, grease (except those specified for use), dust, other impurities, and foreign objects.

We are ball valves suppliers. If you are interested in our products, please feel free to contact us.

Common Faults And Maintenance Of Valves

The cast iron check valve supplier summarizes the common failures of the valve and several reasons for the failure.

1. Common faults of valves

First of all, the reason for the problem is that the operation method of the staff is not in place during the operation, so the limit device cannot fully exert its specific function, and the excessive torque should have a corresponding protective effect, but In the actual operation process, this protection function was not brought into play, resulting in valve failure.

The frequency of use is an important factor affecting the life of the valve. If the valve is used for a long time without sufficient rest, the valve will malfunction. At the same time, some parts are not inspected in detail during the equipment process, resulting in damage to the plump This is also an important reason affecting the use of mechanical equipment.

During the operation, the staff did not handle the switch with care. Once the strength of the operation is not effectively controlled, it will damage the internal structure of the valve and affect the sensitivity of the valve.

The welding process is also the cause of valve failure. A good welding process can ensure the smooth use of the valve. On the contrary, a poor welding process will cause cracks on the surface of the valve, which will adversely affect the use of the valve.

Under normal circumstances, in order to ensure the performance of the valve, the internal packing is an important link, but in actual use, the packing is too compact, which will cause the performance to be affected to a certain extent.

2.Valve maintenance measures

Maintenance of transmission parts

Since the opening and closing of the cast iron check valve will cause the action of the connection part, in the long-term opening and closing action, the lubricating grease previously added will gradually lose, and during the operation, the drying rate of the lubricating grease will be accelerated due to corrosion and temperature. Check the transmission parts frequently and add grease in time. Prevent wear of transmission equipment due to lack of lubricating grease, or transmission failure due to jamming.

Maintenance during valve grease injection

When the valve is greased, the problem of grease injection is often ignored. After the grease gun is refueled, the operator selects the valve and the grease injection connection mode and then performs the grease injection operation. There are two situations:

On the one hand, the amount of grease injection is small, and the grease injection is insufficient, and the sealing surface is worn faster due to lack of lubricant; on the other hand, the grease injection is excessive, causing waste. The sealing capacity can be calculated according to the valve size and category, and then a reasonable amount of grease can be injected.

When the valve is greased, the pressure problem is often ignored. During the fat injection operation, the fat injection pressure changes regularly. If the pressure is too low, the seal will leak or fail; if the pressure is too high, the grease injection port will be blocked, the sealant will harden or the sealing ring will lock up with the valve ball or valve plate. Usually, when the grease injection pressure is too low, the injected grease mostly flows into the bottom of the valve cavity, which usually occurs in small gate valves. If the grease injection pressure is too high, on the one hand, check the grease injection nozzle, if the grease hole is blocked, replace it; on the other hand, if the grease is hardened, use cleaning fluid to repeatedly soften the failed sealing grease and inject new grease to replace it.

Maintenance of packing

The valve packing is an important part to improve the sealing performance. If the packing fails, it will cause leakage and the valve function will fail. Especially when the fluid temperature inside the pipeline is high and corrosive, it will accelerate the aging of the packing, shorten the service life, and affect the function of the valve. Therefore, the maintenance of the filler can improve the efficiency of use. In order to ensure the elasticity of the packing, the static pressure test is the standard when the valve leaves the factory. If leakage occurs during the application process, the nuts on both sides of the packing gland can be tightened to prevent leakage. Don't screw it all at once to prevent the packing from losing its elastic function. In some valve packings, molybdenum disulfide lubricating paste is installed. As the valve is used, lubricating grease should be added regularly to ensure the sealing function.