How to Choose Pipe Flange Materials

When purchasing flanges, you must consider the flange material in addition to physical measurements and bolt hole alignment. The chemical composition and physical properties are important in determining whether a material will be appropriate for a given application. You can look to a combination of standards to guide your decision.

For more information, please visit MIDAS.

What are the different types of flange materials?

Pipes and flanges must be durable enough to withstand heat, pressure, vibrations, and corrosion, while still providing a leak proof seal. Flange class helps determine bolt hole alignment, pressure and temperature rating, and dimensional standards, however, flange material specifications must also be considered based on your application:

Steel is the Most Common Flange material and has higher carbon content for applications requiring superior strength

Stainless Steel is used when high durability and corrosion resistance is required

Aluminum flanges are used for applications where corrosion resistance is important, and a light weight material is required like in irrigation

Ductile Ironoffers a higher yield strength and is lower cost than steel, so preferred for instances where the flange doesn’t come in contact with the medium (like with backing flanges) and cost is an important consideration

The manufacturing method is also important to understand. There are typically three methods used:

Plate flanges are manufactured when metal slabs are sent through rollers until they reach the desired thickness. A plate flange typically costs less, but doesn’t offer the same strength or variety of material and sizes that other manufacturing methods do.

Cast flanges are manufactured by pouring molten metal into a flange mold. The metal cools and hardens, and then the flange is removed from the mold and machined to the appropriate specifications. This lower-cost option offers plenty of flexibility, but does not produce the highest strength flanges.

Forged flanges are made through a process of heating and forming the material, and then machining the part to the proper specifications. This creates the highest strength flange, but comes at a higher cost.

Consider the Intended Application

Choose the right flange material based on its intended use and the requirements specific to that application. Generally, your flange material will match your pipe material, but this is not always the case. Consider the strengths and weaknesses of each material when designing a piping system; the material should suit the application requirements or it may fail prematurely.

Pipe material is chosen based on variables associated with an application, including:

What flows through the pipes (fluids, air, etc.)

Expected high or low temperature

Pressure conditions

Maintenance requirements

Environment

Budget considerations

Certain fluids, for example, fuel or corrosive liquids, require pipes and flanges manufactured of stainless steel, alloy, or other corrosion resistant materials. Pipes and flanges used for air or other non-corrosive applications may not require the same corrosion resistant material as acidic or caustic liquids.

Consult Flange Requirements and Standards

The standards dictate the chemical composition, dimensions, and other specifications for flanges. Generally, your flange and pipe material should meet the same standards.

American Society for Testing and Materials (ASTM) standards—displayed as the “grade” of the material used to manufacture the flange—is determined by the metal’s chemical composition. More specifically, this standard dictates how much carbon and other chemical elements are allowed to make up the raw material.

ASTM A36 is a low-carbon steel favored for its welding properties and is suitable for machining, making it a common material for steel flanges.

ASTM A105 is the standard for carbon steel piping components, particularly for high-temperature applications.

ASTM A182 is the standard for alloy and stainless steel piping flanges and fittings. Alloy steel flanges are produced with more chrome and molybdenum, so they are sometimes preferred for corrosion resistance and can better withstand high temperatures and high pressure.

ASTM A240 is stainless steel plate that offers strength at high temperatures, and high corrosion resistance. While ASTM A182 and ASTM A240 have similar chemical properties, the production method differs: A240 is plate; A182 is forged, which may affect materials choice.

ASTM A536 covers ductile iron, which is used for backing flanges.

Guobiao (GB) standards are issued by the Standardization Administration of China (SAC) and include:

Q235B is a low-carbon steel manufactured in China. The structure allows adequate welding and bolt connection. This steel exceeds AWWA strength requirements and is considered the China comparable material to DIN EN S235JR and ASTM A36 standards (but with slightly lower strengths).

American Water Works Association (AWWA) standards include specifications for steel and stainless steel. AWWA flanges include:

AWWA C207 is the specification for steel ring or slip-on flanges and blind flanges

AWWA C228 is the specification for stainless steel and may use 304L or 316L stainless steel. 304L contains more chromium and less nickel than 316L. The 316L material also includes molybdenum for improved corrosion resistance.

American National Standards Institute (ANSI) and American Society of Mechanical Engineers (ASME) are the industry standards for pipeline flanges in the United States. These standards include B16.1, B16.5, and B16.47 and cover steel, forged, or cast flanges.

Deutsches Institut für Normung (DIN, German Institute of Standardization) is an international standard that applies to steel and stainless steel metric flanges and commonly in maritime applications.

Flange Material Source

It is also important to consider the requirements around where the flange material is sourced from. For many applications it may be fine to us import material in order to save on cost, but often Buy America or Domestic material may be required.

The Buy America standard was developed for government funded transportation projects to provide preference to domestically produced materials, but there are provisions that allow for materials to be sourced from a list of approved countries if it is a small enough part of the total contract, and domestic product availability is low or price is too high.

Our Domestic flanges meet the American Iron & Steel (AIS) standard, which allows imported raw components of the metal, but requires that the flange material be melted and manufactured in the United States.

Domestic flanges are able to be substituted in Buy America applications, and Buy America flanges can be substituted for applications where Import flanges are acceptable, but they can’t be substituted in the other direction.

Other Factors for Choosing Flanges

Consider the pipe material, pressure and temperature ratings, flange dimensions, and tolerances, to determine the appropriate flange material. ANSI ratings provide information on pressure and heat tolerances.

Fitting type is an important consideration as well. Does your fitting require welding? If so, the material you use should allow welding. For non-welded styles, such as lap joint or threaded flanges, weldability is less of a concern, and other requirements will take precedence.

When choosing the ideal flange material, refer to the standards required for your intended application, consider the pipe material that will connect to the flange, and ensure the flange material you choose is rated for the temperature and pressure it must withstand. Or, contact API International, Inc. for assistance with standard fittings or custom machined parts or for further information.

Pressure-temperature ratings ASTM and ASME

Pressure Classes of Flanges

Forged steel flanges ASME B16.5 are made in seven primary Pressure Classes..

150

300

400

600

900

The concept of flange ratings likes clearly. A Class 300 flange can handle more pressure than a Class 150 flange, because a Class 300 flange are constructed with more metal and can withstand more pressure. However, there are a number of factors that can impact the pressure capability of a flange.

Pressure Rating Designation

The Pressure Rating for flanges will be given in Classes.

Class, followed by a dimensionless number, is the designation for pressure-temperature ratings as follows.. Class 150 300 400 600 900 .

Different names are used to indicate a Pressure Class. For example.. 150 Lb, 150 Lbs, 150# or Class 150, all are means the same.

But there is only one correct indication, and that is Pressure Class, according to ASME B16.5. (the pressure rating is a dimensionless number).

Example of Pressure Rating

Flanges can withstand different pressures at different temperatures. As temperature increases, the pressure rating of the flange decreases. For example, a Class 150 flange is rated to approximately 270 PSIG at ambient conditions, 180 PSIG at approximately 400°F, 150 PSIG at approximately 600°F, and 75 PSIG at approximately 800°F.
In other words, when the pressure goes down, the temperature goes up and vice versa. Additional factors are that flanges can be constructed from different materials, such as stainless steel, cast and ductile iron, carbon steel etc.. Each material have different pressure ratings.

Below an example of a flange NPS 12 with the several pressure classes. As you can see, inner diameter and diameter of the raised face at all the same; but outside diameter, bolt circle and diameter of bolt holes become larger in each higher pressure class.

The number and diameters (mm) of the bolt holes are..

Class 150▸ 12 x 25.4

Class 300▸ 16 x 28.6

Class 400▸ 16 x 34.9

Class 600▸ 20 x 34.9

Class 900▸ 20 x 38.1

Class ▸ 16 x 54

Class ▸ 12 x 73

Pressure-Temperature Ratings - Example

Pressure-temperature ratings are maximum allowable working gage pressures in bar units at the temperatures in degrees celsius. For intermediate temperatures, linear interpolation is permitted. Interpolation between class designations is not permitted.

Pressure-temperature ratings apply to flanged joints that conform to the limitations on bolting and on gaskets, which are made up in accordance with good practice for alignment and assembly. Use of these ratings for flanged joints not conforming to these limitations is the responsibility of the user.

The temperature shown for a corresponding pressure rating is the temperature of the pressure-containing shell of the component. In general, this temperature is the same as that of the contained fluid. Use of a pressure rating corresponding to a temperature other than that of the contained fluid is the responsibility of the user, subject to the requirements of applicable codes and regulations. For any temperature below -29°C, the rating shall be no greater than the rating shown for -29°C.

As an example, below you will find two tables with material groups ASTM, and two other tables with flange pressure-temperature ratings for those ASTM materials ASME B16.5.

ASTM Group 2-1.1 Materials
Nominal
Designation Forgings Castings Plates C-Si A105(

1

) A216
Gr.WCB (

1

) A515
Gr.70 (

1

) C Mn Si A350
Gr.LF2 (

1

)   A516
Gr.70 (

1

), (

2

) C Mn Si V A350
Gr.LF6 Cl 1 (

3

)   A537
Cl.1 (

4

) 3.1/2Ni A350
Gr.LF3    

  Notes..

(

1

) Upon prolonged exposure to temperatures above 425°C, the carbide phase of steel may be converted to graphite. Permissible but not recommended for prolonged use above 425°C.(

2

) Do not use over 455°C.(

3

) Do not use over 260°C.(

4

) Do not use over 370°C.
ASTM Group 2-2.3 Materials
Nominal
Designation Forgings Castings Plates 16Cr 12Ni 2Mo A182
Gr.F316L   A240
Gr.316L 18Cr 13Ni 3Mo A182
Gr.F317L     18Cr 8Ni A182
Gr.F304L (

1

)   A240
Gr.304L (

1

)

  Note..

(

1

) Do not use over 425°C.

Pressure-Temperature Ratings for ASTM Group 2-1.1 Materials
Working pressure by Classes, BAR

Temp
-29 °C 150 300 400 600 900 38 19.6 51.1 68.1 102.1 153.2 255.3 425.5 50 19.2 50.1 66.8 100.2 150.4 250.6 417.7 100 17.7 46.6 62.1 93.2 139.8 233 388.3 150 15.8 45.1 60.1 90.2 135.2 225.4 375.6 200 13.8 43.8 58.4 87.6 131.4 219 365 250 12.1 41.9 55.9 83.9 125.8 209.7 349.5 300 10.2 39.8 53.1 79.6 119.5 199.1 331.8 325 9.3 38.7 51.6 77.4 116.1 193.6 322.6 350 8.4 37.6 50.1 75.1 112.7 187.8 313 375 7.4 36.4 48.5 72.7 109.1 181.8 303.1 400 6.5 34.7 46.3 69.4 104.2 173.6 289.3 425 5.5 28.8 38.4 57.5 86.3 143.8 239.7 450 4.6 23 30.7 46 69 115 191.7 475 3.7 17.4 23.2 34.9 52.3 87.2 145.3 500 2.8 11.8 15.7 23.5 35.3 58.8 97.9 538 1.4 5.9 7.9 11.8 17.7 29.5 49.2

Pressure-Temperature Ratings for ASTM Group 2-2.3 Materials
Working pressure by Classes, BAR

Temp
-29 °C 150 300 400 600 900 38 15.9 41.4 55.2 82.7 124.1 206.8 344.7 50 15.3 40 53.4 80 120.1 200.1 333.5 100 13.3 34.8 46.4 69.6 104.4 173.9 289.9 150 12 31.4 41.9 62.8 94.2 157 261.6 200 11.2 29.2 38.9 58.3 87.5 145.8 243 250 10.5 27.5 36.6 54.9 82.4 137.3 228.9 300 10 26.1 34.8 52.1 78.2 130.3 217.2 325 9.3 25.5 34 51 76.4 127.4 212.3 350 8.4 25.1 33.4 50.1 75.2 125.4 208.9 375 7.4 24.8 33 49.5 74.3 123.8 206.3 400 6.5 24.3 32.4 48.6 72.9 121.5 202.5 425 5.5 23.9 31.8 47.7 71.6 119.3 198.8 450 4.6 23.4 31.2 46.8 70.2 117.1 195.1

FULL LIST OF ASTM MATERIAL SPECIFICATIONS

Remark(s) of the Author...

150lb - 150lbs - 150# - Class 150

LB is the origin of the Latin word libra (weighing scale), and describes a Roman unit of mass similar to a pound.
The full expression was librapondo, and we have invented acronyms such as..
lb = one pound, lbs = more pounds, # = Abbreviation for pound

Text below is from www.worldwidewords.org copyright © of Michael Quinion

The form lb is actually an abbreviation of the Latin word libra, which could mean a pound, itself a shortened form of the full expression, libra pondo, "pound weight". The second word of this phrase, by the way, is the origin of the English pound.

You will also know Libra as the astrological sign, the seventh sign of the zodiac. In classical times that name was given to rather an uninspiring constellation, with no particularly bright stars in it. It was thought to represent scales or a balance, the main sense of libra in Latin, which is why it is often accompanied by the image of a pair of scales.
Libra for a pound is first found in English in the late fourteenth century, almost at the same time as lb started to be used. Strictly speaking again, this was the Roman pound of 12 ounces, not the more modern one of 16. And just to consolidate my reputation for careful description, modern metrologists, scientists who study units of measurements, would prefer that we don't use lbs at all; in scientific work, all units are singular.

Incidentally, another abbreviation for libra became the standard symbol for the British pound in the monetary sense. In modern times it is usually written £, an ornate form of L in which a pair of cross-strokes (often just one these days) were the way that a medieval scribe marked an abbreviation. The link between the two senses of pound, weight and money, is that in England a thousand years ago a pound in money was equivalent to the value of a pound of silver.

For more All Flanged Crossinformation, please contact us. We will provide professional answers.

Related Post(s)

Types of Flanges
Flanges - ASME B16.5 - Inch Dimensions - Weld Neck/Stud Bolts Class 150 to Class ...

Article

Everything About ANSI Flange Pressure Ratings Charts

What Is ANSI Flange Rating And Flange Class?

Each pipe fitting retains a certain pressure holding ability that is determined by the type and thickness of the metal. A flange is one of the essential parts of a pipe that connects to industrial valves, tools, and other spools of piping and carries the pressure created in the piping system during the operation.

The term “flange pressure rating” refers to a particular classification that specifies the ultimate temperature at which a given flange can withstand a given amount of pressure. The utmost pressure a flange can resist with growing temperature up to a limit for a certain temperature span is indicated by the flange pressure rating or class.

The American National Standards Institute, also known as ANSI, is a nonprofit, independent association that assists in regulating the standards for a variety of goods, services, operations, and personnel. One can be sure to get the appropriate flange given the material and the maximum pressure and temperature to which it will be subjected by looking at the ANSI rating.  

Seven flange pressure ratings are delivered by the ASME or ANSI B16.5 standard, which are: 150, 300, 400, 600, 900, , and . Additionally referred to as the flange class, they are identified by the class and observed by any of the dimensionless integers. The terms “pound rating” and “pressure class rating” are also used to describe them. 

Here are some vital features of flange classes are:

If the flange rating is high, the more pressure and temperature flanged valve can resist.

In comparison to flanges with less grades, those with higher values are thicker, heavier, and stronger.

Because flange dimensions fluctuate as pressure rating classes change, a flange from one pressure class might not match with a flange from an elevated or lower class.

The number of bolts grows along with the pressure rating, boosting the bolt area. By improving the bolt’s capacity to carry force and moment, the gain in bolt area decreases the potential for flange leakage. 

What To Know About ANSI Flange Pressure Rating Chart

Flanges, valves, and fittings are governed by a variety of standards, but ANSI pressure ratings are arguably the most widely used set of guidelines. There are seven distinct ANSI flange pressure ratings. The flange will be smaller, lighter, and less robust if the flange rating is less. It is best to acquire high-quality valves for the desired applications from a reliable valve manufacturer. 

140 pounds psi is the most that a class-150 carbon steel flange can resist when exposed to 600 degrees Fahrenheit. A class-300 flange with identical other specifications can sustain 570 psi. With the exact substance and bore size, a class- flange can sustain up to psi, which is 34 times more pressure compared to a 150-class flange. 

ANSI flanges are utilized for all applications other than oil drilling and well heading. For flanges up to 24 inches in diameter, ANSI B16.5 is utilized, and for flanges larger than 24 inches, ANSI B16.47 is employed. 

Pressure Rating Designation Of Flanges 

The results of the ANSI pressure rating chart are displayed in Class, Lb, or Pound. The designation of the pressure-temperature rating of flanges is class, which is followed by an arbitrary number. There are seven different sorts of flange rating designations, each denoted by a “#”: 

150#

300#

400#

600#

900#

#

#

The pound system is represented by the symbol “#,” which is also symbolized by “Lb.” Numerous designations, including 150 Lb, 150 Lbs, 150#, and Class 150, are used to identify flanges and these all signify the same thing. However, there is just one signal that is accurate, which is “Pressure class.” 

All of these signs just represent the idea of a flange’s pressure or temperature capability for valves and are interchangeable. This pressure or temperature performance is crucial since it aids in the selection of the best flange for the circumstances.

A Brief Guide To ANSI Flange Pressure Rating Chart 

Check out the details of the ANSI flange pressure ratings chart about class 1 flanges.  

Class 150 

If the temperature for Class 1 150# flange is

If the temperature for Class 1 150# flange is 200 degrees Fahrenheit, the maximum pressure for flanges is 260 psi. 

If the temperature for Class 1 150# flange is 300 degrees Fahrenheit, the maximum pressure for flanges is 230 psi.

If the temperature for Class 1 150# flange is 400 degrees Fahrenheit, the maximum pressure for flanges is 200 psi.

If the temperature for Class 1 150# flange is 500 degrees Fahrenheit, the maximum pressure for flanges is 170 psi.

If the temperature for Class 1 150# flange is 600 degrees Fahrenheit, the maximum pressure for flanges is 140 psi. 

If the temperature for Class 1 150# flange is 700 degrees Fahrenheit, the maximum pressure for flanges is 110 psi.

If the temperature for Class 1 150# flange is 800 degrees Fahrenheit, the maximum pressure for flanges is 80 psi.

If the temperature for Class 1 150# flange is 900 degrees Fahrenheit, the maximum pressure for flanges is 50 psi.

If the temperature for Class 1 150# flange is degrees Fahrenheit, the maximum pressure for flanges is 20 psi. 

Class 300 

If the temperature for Class 1 300# flange is

If the temperature for Class 1 300# flange is 200 degrees Fahrenheit, the maximum pressure for flanges is 680 psi.

If the temperature for Class 1 300# flange is 300 degrees Fahrenheit, the maximum pressure for flanges is 655 psi.

If the temperature for Class 1 300# flange is 400 degrees Fahrenheit, the maximum pressure for flanges is 635 psi.

If the temperature for Class 1 300# flange is 500 degrees Fahrenheit, the maximum pressure for flanges is 605 psi.

If the temperature for Class 1 300# flange is 600 degrees Fahrenheit, the maximum pressure for flanges is 570 psi.

If the temperature for Class 1 300# flange is 700 degrees Fahrenheit, the maximum pressure for flanges is 530 psi.

If the temperature for Class 1 300# flange is 800 degrees Fahrenheit, the maximum pressure for flanges is 410 psi.

If the temperature for Class 1 300# flange is 900 degrees Fahrenheit, the maximum pressure for flanges is 230 psi. 

If the temperature for Class 1 300# flange is degrees Fahrenheit, the maximum pressure for flanges is 85 psi. 

Class 400 

If the temperature for Class 1 400# flange is

If the temperature for Class 1 400# flange is 200 degrees Fahrenheit, the maximum pressure for flanges is 905 psi. 

If the temperature for Class 1 400# flange is 300 degrees Fahrenheit, the maximum pressure for flanges is 870 psi. 

If the temperature for Class 1 400# flange is 400 degrees Fahrenheit, the maximum pressure for flanges is 845 psi. 

If the temperature for Class 1 400# flange is 500 degrees Fahrenheit, the maximum pressure for flanges is 805 psi. 

If the temperature for Class 1 400# flange is 600 degrees Fahrenheit, the maximum pressure for flanges is 755 psi. 

If the temperature for Class 1 400# flange is 700 degrees Fahrenheit, the maximum pressure for flanges is 710 psi. 

If the temperature for Class 1 400# flange is 800 degrees Fahrenheit, the maximum pressure for flanges is 550 psi. 

If the temperature for Class 1 400# flange is 900 degrees Fahrenheit, the maximum pressure for flanges is 305 psi. 

If the temperature for Class 1 400# flange is degrees Fahrenheit, the maximum pressure for flanges is 115 psi. 

Class 600 

If the temperature for Class 1 600# flange is

If the temperature for Class 1 600# flange is 200 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 600# flange is 300 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 600# flange is 400 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 600# flange is 500 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 600# flange is 600 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 600# flange is 700 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 600# flange is 800 degrees Fahrenheit, the maximum pressure for flanges is 825 psi. 

If the temperature for Class 1 600# flange is 900 degrees Fahrenheit, the maximum pressure for flanges is 460 psi. 

If the temperature for Class 1 600# flange is degrees Fahrenheit, the maximum pressure for flanges is 170 psi. 

Class 900 

If the temperature for Class 1 900# flange is

If the temperature for Class 1 900# flange is 200 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 300 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 400 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 500 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 600 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 700 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 800 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 900# flange is 900 degrees Fahrenheit, the maximum pressure for flanges is 690 psi. 

If the temperature for Class 1 900# flange is degrees Fahrenheit, the maximum pressure for flanges is 255 psi. 

Class  

If the temperature for Class 1 # flange is

If the temperature for Class 1 # flange is 200 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 300 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 400 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 500 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 600 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 700 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 800 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 900 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is degrees Fahrenheit, the maximum pressure for flanges is 430 psi. 

Class  

If the temperature for Class 1 # flange is

If the temperature for Class 1 # flange is 200 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 300 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 400 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 500 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 600 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 700 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 800 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is 900 degrees Fahrenheit, the maximum pressure for flanges is psi. 

If the temperature for Class 1 # flange is degrees Fahrenheit, the maximum pressure for flanges is 715 psi. 

What Is The Effect Of Flange Pressure Rating On Flange Size 

A method of grouping different pressure-temperature established ratings of flanges as per the flange material is known as flange pressure rating. There are a few aesthetic characteristics that distinguish a lower-class flange from a higher-class flange: 

A flange with a comparatively higher grade is thicker and has greater pressure and temperature resistance.

The flange’s outside diameter will grow as the flange pressure rating does. 

In accordance with the flange pressure rating, the bolt circle diameter will rise.

With higher flange classes comes larger bolt holes and more bolts to install.

Higher flange ratings also result in wider flange faces.

Conclusion 

At some particular temperature requirements, a flange with an elevated rating or class is more powerful than a flange with less rating or class. If they are constructed of the same material and have a higher grade, flanges can tolerate more pressure and heat. At the exact rating and flange class, a flange manufactured of a distinct material will have a varied holding capability for pressure and temperature. 
Flanged valves play an important role in every industrial application, hope this article could help you find the best valve for your application. If you need high quality flanged valves, feel free to contact Dombor, flanged butterfly valve or ball valves are all available.

Specification: DN50-DN(2"-80"), available with PN10, PN16, PN25 and PN40 flanges    

Ductile Iron Flange Fittings Standard: ISO, ISO, ISO, BS EN 545, BS EN598, BS, ISO-2, EN-2:, DIN, GBT    

Flange: PN10, PN16 or PN25 drilling in accordance with ISO -2/EN -2.    

Fluid Temperature: 0°C-50°C， excluding frost.    

Pipe ends: Spigot, socket or flanges.    

Internal coating: Cement mortar lining comply with ISO or bitumen painting (Ave. min.70 micron) or Fusion Bonded Epoxy Coating    

External coating: Sprayed metallic zinc coating (min.150g/m²) according to ISO + bitumen painting (min.70 micron) or epoxy powder coating or epoxy painting or according to customer’s requirements.    

Types: Dismantling Joint, Universal Flange Adaptor, Universal Coupling, Ductile Iron Loose Flange Joint, DI Pipe Fitting, Saddle for PVC Pipe, Repair Clamp, Qucick Flange Adaptor, Gibault Joint, Restrained Flange Adaptor, Restrained Coupling, Valve, etc.    

Material: MATERIAL: Ductile iron grade 500-7/ 450-12 in accordance with ISO for ductile iron fitting body and retainer, EPDM/NBR for ring, steel zinced/dacro for stub.    

Application: Municipal Use, Waterworks Pipelines, Piping Fittings, Water Engineering, Potable Water Use, Irrigation Use, Water Supply Project Use, Water Treatment Plants Use, Pumping Stations, Water Utility Sectors, Water-Supply Pressure Pipeline, Potable Water Pumping Station, Stormwater Lines, Fire Water Pumping Station, Fresh Water Pumping Station, ect.    

Test: In accordance with ISO / EN 545 / EN598 and 100% water pressure test.    

All Loosing Flanged Tee All Loosing Flanged Cross Double Loosing Flanged Duckfoot Bend Double Loosing Flanged anchoring Sleeve Loosing Flanged Spigot Loosing Flange Set . Standard: ISO,EN545,EN598 Pressure: PN10/PN16/PN25/PN40 Body material : Ductile iron Coating: a). Inside and outside with FBE ( fusion bonded epoxy) coating or Epoxy. As the Ductile Iron All Loosing Flanged Tee manufacturer in China and Ductile Iron All Loosing Flanged Tee factory, we hope working with you, we are eager to get your inquiries and establish long term mutual benefit cooperation relationship.    

Dimensions of All Loosing Flanged Cross    

The company is the world’s best All Flanged Tee supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.