How to select Butterfly valve?

The highest reliability and lower maintenance quotient of the butterfly valve propelling the growth in the global market, wherein wastewater treatment, power generation, pharmaceutical, paper processing, food, beverage and fine chemical industries are the one which are significantly approaching butterfly valve to accomplish throttling or controlling of the respective media in the fluid system and therefore we have made it available in the wide variety of the specification and configuration ranging from 1 to over 200 and pressure capabilities ranging from 150 psi to 750 psi, available in manual as well as automatically actuated modes.

This butterfly valve can be used either as an on/off or as a controlling/ modulating device and according to the application requirement, it is necessary to select a righteous type of the butterfly valve in order to ensure its effectiveness to the highest. We manufacturer of the butterfly valve illustrates the major area of the concern to be considered while selecting the butterfly valve which are seat material, body style (wafer or lug), and stem design.

Selecting the Right Style:

The butterfly valve comes in a variety of the style incorporating, lug, wafer, semi lugged, double flange, wherein the wafer style is one of the cheapest and safest type in the industries, while lug style facilitates in eliminating downstream piping. However, wafer is the widely preferred in the industries for its light weight aspect, enabling easy installation without extra efforts and cost.

Selecting Stem Designs:

The stem design of the butterfly valve is principally available in two types, which are one-piece and two-piece. This stem of the butterfly valve contacts to the fluid media all the time during application and hence the selection of the right material is crucial, especially for a high performance application. Generally, it is recommended to go with the corrosion resilient material to prevent it from corrosion and thus ensure longer life of the stem.

Selecting the Right Seat Material:

The material of the seat decides the quality of the butterfly valve, and therefore the material selection of the seat plays prominent role in the quality of the butterfly valve. The number of factors of needs to be considered while selecting seat material, accounts chemical compatibility, temperature, pressure, wear and cost. We manufacturer of the butterfly valve provides this majorly in PTFE and RTFE that are sequentially also known as Polytetrafluroethylene and Polytetrafluroethylene for their considerable abrasion resistance, thermal and electrical insulation aspects. However, we also provide this seat in the Ultra-high Molecular Weight Polyethylene (UHMWPE) that is being notable in the market for its excellent chemical resistance as well as corrosion resistance.

Property EPDM NEOPRENE VITON SILICONE
Temperature -55 to 275 F -40 to 255 F -20 to 400 F -80 to 450 F
Resistance to Acid Good – Excellent Good Good Good
Resistance to Alkali Good – Excellent Fair-Good Poor-Good Poor-Good
Resistance to Petroleum Oil Poor Excellent Excellent Good
Resistance to Vegetable Oil Good Good Excellent Good
Resistance to Abrasion Good-Excellent Good Good Good-Excellent
Compression Set Fair Good Good-Excellent Good-Excellent
Seat Material General Application Temperature Range Environments Not Suggested
NITRILE
BUNA-N (NBR)
Hydrocarbons with less than 40% of aromatics, natural gas, air, H2O, sea water, brine, alcohols, glycols (food grade available) 14°F to 176°F solvents, benzene, xylene
-10°C to 80°C
EPDM H2O, steam, air, brine, abrasives,phosphates, esters, ketones, alkali, foodcompounds, liquids and solids, diluted inorganic acids, caustic soda(food grade available) -4°F to 250°F
-20°C to 120°C
hydrocarbons, oils,fats, dry air
HIGH TEMP EPDM -4°F to 300°F
-20°C to 148°C
Hypalon (CSM) Oxidizing acids, chromic acid,hydrofluoric acid, sulphur based acids, sodium hypoclonte, ozone 0°F to 212°F steam, ketones,hot air, nitric acid
-18°C to 100°C
Silicone Beverages, food -22°F to 300°F hydrocarbons,solvents, steam
-30°C to 150°C
Fluoroelastomer

(FKM)

Hydrocarbons with high concentration of aromatics, mineral and halogenated acids, phosphoric acid, aliphatic and

aromatic ethers

0°F to 400°F steam, ketones,amines, esters, alkali
-18°C to 205°C
Neoprene (CR) Oils, diluted mineral acids, alkali, fats -4°F to 212°F ketones,concentrated acids,solvents for paint
-20°C to 100°C
Natural Rubber Abrasive products -40°F to 176°F steam,hydrocarbons, oils
-40°C to 80°C
PTFE/EPDM Corrosive products, solvents -4°F to 250°F abrasive products,fluorine gases,alkaline metals
-20°C to 120°C

For any query in regard to butterfly valve, don’t hesitate to talk back, our team have considerable years of experience and is happy to help..!

What’s different about zero, double and triple offset butterfly valves?

Every application has different necessity and hence we have introduced different types of the butterfly valve with different offsets sequentially, zero, double and triple. Among three types, selecting the right is crucial, as a wrong selection of the butterfly valve can result in disadvantageous. Here, we manufacturer of the butterfly valve have delineated each profoundly for your support.

Zero Offset butterfly valve/ Concentric Design:

The zero offset design generally found in the resilient seated or rubber seated butterfly valves, wherein the stem and disc are centered in the seat of the valve, and all of which are centered in the body of the valve. The sleeve type construction of the body or cartridge within the construction of the body prevents media from contacting the body and hence it is wise selection to use in basic and specialty liquid and gas applications up to 200 PSI and up to 400 F. however, we recommend this zero offset valve for handling different types of chemicals, coatings, food and abrasive liquids.

Available in epoxy coated cast iron and stainless steel with multiple seat material such as EPDM, VITON, Teflon, Buna, Natural rubber, etc.

Recommended application area:

Chemicals, coatings, food and abrasive liquids

Double Offset Butterfly Valve / High Performance:

The double offset butterfly valve has two stems offset from the center and for the reason it is named double offset. The exclusive double offset design of this type of butterfly valve creates mechanical cam action during the application. This double offset butterfly valve has great capability to perform under high pressure than zero offset style and therefore is perfect for higher pressure applications up to ANSI class 600 rating, available in carbon steel and stainless steel material. However, other materials are available on the customer request.

Recommended application area:

Chemical, Oil and gas, Water and wastewater treatment, Power generation, Pulp and paper, Shipbuilding and HVAC

Triple Offset Butterfly Valve

This type of the butterfly embraces three offsets; two are placed in same position, whilst the third creates cone shape geometry. This cone angle and two other eccentric shat offsets, permits the disc to uniformly seal against the seat without any friction and therefore tight shutoff. The low cost and easy to automate featuring of this valve has replaced the gate valve, wherein a metal seat is essential and tight shutoff and turn actuation is desired. The selection of the triple offset butterfly valve would be the virtuous for the high pressure steam over 150 PSI and also can be used in all the industries where double offset is used but the précised shutoff is more demanding.

Recommended application area:

High temperature gases and oils, superheated steam, high pressure steam

For any query in regard to offset of butterfly valve, don’t hesitate to talk back, our valve team have considerable years of experience and is happy to help..!

Which material to select for the butterfly valve body?

We manufacturer of the butterfly valve have used a variety of material in the construction of the butterfly valve in order to carry of elite incorporation that is best to accomplish excellent functionality in a cost efficient manner. Below is detailed information about the material we employ in the construction to deliver nothing, but the highest quality range of the butterfly valve for your application needs.

Carbon Steel:

It is an incorporation of the iron and carbon, there is no other elements are mixed within to alter the characteristics. The body and disc are two major units of the butterfly valve, in which we use carbon steel as the material of construction by means of the sand casting process. For the high temperature WCB is used, whilst for low temperature applications, LCC is used.

Advantageous side:

Cast iron is cheap and therefore is a prime choice, if cost is concern than other aspects. However, it is poor against resistance, which can be overcome by paint.

Stainless Steel:

It is a combination of an iron and chromium content of approx 10%, wherein the chromium itself develops a layer of chromium oxide on the surface of the material by reacting with oxygen in the air. When the material undergoes scratches, the chromium in the stainless steel quickly reacts with the oxygen and prevents oxygen to react with iron and develop iron oxide (rust). Furthermore, austenitic and duplex stainless steel materials are widely used in the construction of the valves, the answer for why is here:

Austenitic stainless steels

It is a combination of the iron, chromium and nickel, having the potential to retain face centred cubic austenitic structure at high temperatures, where it would normally have converted to ferritic body centred cubic structure. The use of austenitic stainless steel in the construction of the butterfly valve helps enhance toughness and ductility, unlikely to the ferritic grades. Likewise, it is potent to retain the structure, even at lower temperatures too, and therefore is the best for high and low temperature applications.

Duplex stainless steels

It is a combination of austenitic face centred cubic and ferritic body centred structure of iron, carried out by meticulously controlling both alloy elements and the heat and therefore it holds the higher strength of ferrite, whilst toughness of austenite. Furthermore, the considerable amount of the chromium and molybdenum inside helps improve the resistivity of the stainless steel against crevice corrosion.

Nickel Alloys

It is a combination of the iron, chromium and nickel, which is one of the toughest material used in the construction of the butterfly valve, where stainless steel is no more effective due to the harsh corrosive environments. Among many, hastelloy nickel alloy is prominently used in the construction of the valve.

Titanium Alloys

It is an incorporation of the iron, chromium and titanium, sharing high strength to weight ratio, light weight and outstanding corrosion resistance, which protects itself from the corrosion just as stainless steel. Moreover, this titanium alloy known for specifically having greater resistance to corrosion by seawater, and therefore getting high attention where hypochlorite is present to avert biofouling. However, the higher cost is a concern and therefore used only when crucial.

Nickel Aluminum Bronze

It is a combination of the nickel, aluminum and iron with sequentially 5%, 10% and 5% of an alloy, known for holding excellent corrosion resistance, especially in seawater surroundings. Other than, it’s notably resist to the formation of bio film, which is a major cause for the corrosion issue in stainless steel and most delightful, is the cost efficient approach.

For any query in regard to butterfly valve material, don’t hesitate to talk back, our valve team have considerable years of experience and is happy to help..!

Application perspective which butterfly valve is right?

The ambiguity of the selection is apparent and to help out in that, we manufacturer of the butterfly valve have differentiated in two main types based on the application, which are:

General Service Butterfly Valve:

As manifested from a name, general service butterfly valve used for the general purpose applications. This type of valves can be operated by means of the handle, air actuator or electric actuator and hence can achieve constant and long term throttling, on/off and isolation control during the application. This is a cost effective alternation that is expansively used in variegated applications, incorporating air, steam, water and other inert gases, thanks to the seat configuration permits for operation in vacuum application, basically available in the wafer or lug type design to comply with piping process applications.

This general purpose butterfly shares higher torques than the high performance butterfly valve, whilst the material of the seat constrains the higher temperature range of the valve. We as manufacturer of the butterfly valve recommend this type of valve to select for the application having pressure up to 280 PSI.

High performance butterfly valve:

This type of butterfly valve is specifically designed to achieve incredible shutoff and throttling control in the various applications. They can be operated under normal conditions, however ideal for viscous and corrosive media too. The seat of the butterfly is equipped owing the area of application, like PTFE seat is used for the bubble tight shutoff in multi directional; soft seat with the metal seat is available for higher temperature, whereas fire safe seats are also available if essential.

The available construction material is ranging from carbon steel to stainless steel, whereas the temperature from 20 to 900 F as per seat configuration, available in the wafer or lug design and can be operated manually or by means of an actuator.

For any query in regard to the butterfly valve selection, don’t hesitate to talk back, our valve team have considerable years of experience and is happy to help..!

Booted, molded, or cartridge: which is the best seat for butterfly valves?

The butterfly valve is highly demanded worldwide for its ingenious design, outstanding performance and cost efficient measures. We manufacturer of the butterfly valve provides this in a wide variety of the specification, however resilient seated butterfly valve is the one that being used considerably in the fluid control applications for its some of the incredible features, including versatility, cost effective and easy operation ability.

In this type of the butterfly valve, functionality of the valve vastly relies on the seat, equipped between pipe flanges and the disc, whereas the seat relies on the disc to achieve the quality level of contact with the seat, required for the proper sealing. Therefore, selecting a right style of the seat is pivotal for the excellent performance.

Booted or Dovetail Seat

This seat is exclusively designed in the dovetail shape for best fit with the inner diameter of the valve body. There is no bonding agent is used during the fitting and hence it can be easily removed and serviced. However, when it comes to reliability measures of this type of the seat, it is prone to movement and has a tendency to deform in the mounting conditions that bounds limit on its usage.

Molded Seat

To prevent the movement of the seat, in this type molded style seat is attached to the body of the butterfly valve manufacturer in usa by means of the injection molding technology helps achieving the effective bond between seat and valve body. This style of seat resists deformation as well as dislocation all through the valve mounting and is significantly more versatile than that of the booted style. However, in case of damage, the entire valve needs to be replaced, as the bonded seat is non removable.

Cartridge Seat

This type of seat is accomplished by means of compression molding a layer of elastomer onto a stiff body of the phenolic backing ring that empowers the elstomer in variegated directions. The compression molding technology used in the elastomer seat formation is far better than an injection molding process that not only renders constant pressure in the construction of seat shape but also regulates seat dimensions. This type of the seat is being extensively popular for its highest resistance to wear along with the best torque consistency measure. This cartridge style seat is being the preferable alternative in the highly abrasive applications, where valve need to be replaced on the regular basis. The use of the cartridge style seat eliminates the need valve replacement, thanks to the replaceable aspect of the cartridge style seat.

For any query in regard to the seat style selection, don’t hesitate to talk back, our valve team have considerable years of experience and is happy to help..!