ANSI Flange

Our company offers ANSI flanges in different sizes and materials.

ANSI flanges are American Standard flanges, which refers to the flange standards developed by the American National Standards Institute.
ANSI it is common size is 1/2 “-24”, pressure from Class150 to Class2500. ANSI standard specification of different types of different pressure flange size specifications and other data, provides a unified reference standard, can ensure that different flange manufacturers produce flanges can be replaced with each other to use, and improve the efficiency of work.

ansi 1

ASME/ANSI B16.47 Flanges

Size from 26” – 60” class 75 to class 900


ASME/ANSI B16.5 Flanges

Size from 1/2” – 24” class 150 to class 2500


ANSI Flanges

ANSI flanges are American Standard flanges, which refer to the flange standards developed by the American National Standards Institute.
ANSI its common size is 1/2 “-24”, pressure from Class150 to Class2500. ANSI standard specification of different types of different pressure flange size specifications and other data provides a unified reference standard, can ensure that different flange manufacturers produce flanges that can be replaced with each other to use, and improve the efficiency of work.

The origin of ANSI flange

With the continuous development of industry, the application of flanges is more and more frequent, a variety of different specifications and sizes of flanges will bring a lot of follow-up problems, operation, and replacement of difficult, this time to formulate a unified standard has become particularly important.
American Standard ANSI flange standard was born, American Standard ANSI flange was established in 1918, it is led by the American National Standards Institute, a non-profit organization, and then through the participation of experts in many professional fields, after extensive discussions and public review, and ultimately made to meet the needs of a variety of industrial applications of the standards, referred to as ANSI standards. It is referred to as the ANSI standard.

ANSI flange performance parameter table

Standard:ANSI B16.5 (flanges between 1/2 inch and 24 inches in size)
ANSI B16.47 (flanges between 26 inches and 60 inches)
Types:Weld Neck Flange, Blind Flange, Slip-On Flange, Socket Weld Flange and Threaded Flange.
Size:1/2″ – 60″
Pressure Rating:Class150, Class300, Class600, Class900, Class1500, Class2500.
Material:Common ANSI flanges are made of carbon steel (ASTM A105, ASTM A350 LF2), stainless steel (ASTM A182 F304, ASTM A182 F316), alloy steel (ASTM A182 F11, ASTM A182 F22, ASTM A182 F91) and other materials.
Sealing Face:Flat Face(FF), Raised Face(RF), Male and Female Face(MF), Tongue and Groove Face(TG), Ring Joint Face(RJ)
Connection:Bolt connection, Butt welding connection, Socket welding connection, Threaded connection.
Fabrication Process:Forged Flanges (Design->Raw Material Selection->Preheating->Forging->Processing->Welding->Heat Treatment->Surface Treatment->Testing and Inspection->Packaging and Delivery)
Casting Flanges: (Design->Mold Making->Raw Material Selection->Casting->Cleaning and Dressing->Machining->Testing and Inspection->Surface Treatment->Packaging and Delivery)
Application areas:In various equipment, pumps, valves, pipelines, and other engineering systems in the petroleum, natural gas, chemical, electric power, construction, ocean engineering, and other industries.
ANSI flange performance parameter table

How to choose the ANSI flange?

  1. Determine the demand: first determine the project needs to apply the flange to connect the pipeline diameter, pressure level, medium corrosivity, temperature, and other specific parameters.
  2. Determine the flange specifications: according to the first step we determine the data reference ANSI B16.7, ANSI B16.5, and other relevant standards and norms to select the flange specifications and pressure level.
  3. Choice of material: according to the pressure in the pipeline, the corrosive properties of the medium, and the temperature choose the appropriate material.
  4. Sealing surface: sealing performance in the flange is very important, must strictly and carefully follow the rules to select the correct form of sealing surface and sealing gasket to ensure the sealing performance of the flange connection.
  5. Connection: according to the site installation conditions choose the appropriate installation connection.
  6. Reliable suppliers: choose ANSI flange not only to pay attention to the above parameters but also to find a reliable supplier, the requirements of the production of flanges are in line with the requirements of ANSI, with no error, it is best that provide the relevant certificates and inspection reports.
  7. The price is reasonable: the above is no problem, we also need to consider the overall cost, more compared to selective high-price manufacturers to purchase.

ANSI flange installation tutorial

To let you better use ANSI flange for your project service, here we tell you about ANSI flange installation step

  1. Preparation tools: prepare in addition to the flange, bolts, nuts, gaskets, other than the installation of tools needed, such as torque wrenches, manual wrenches, wrench sockets, leveling, vertical meter, jacks, lifting equipment, gasket fixtures, metrology tools, bolt cutting tools, lubricants, protective equipment, including gloves, safety goggles, earplugs, etc., as well as welding equipment, including welders, welding materials, and so on.
  2. Check the flange: check to make sure it is the standard flange specified in the project, check the appearance of the flange is completely unbroken, to ensure that the size is accurate and language-free.
  3. Align the flange: the first step of installation is to align the bolt holes and flange holes of the flanges that need to be connected.
  4. Installation of bolts: put the sealing gasket, put the bolts into the bolt holes according to the just aligned bolt holes, and align the nuts.
  5. Fasten the bolts: screw the bolts into the nuts, and then use the wrench to fasten, this process should strictly comply with the engineering requirements to ensure that the required solid state. Ensure that the flange is not shifted during the fastening process.
  6. Welding flange: butt-welding and flat-welding flanges need to be welded, strictly by the provisions of the standard program first spot welding and then all welded to ensure that there is no leakage welding.
  7. Check the sealing effect: comprehensively check whether the connection is sealed, if there is a problem to be corrected in time, and if there is still a gap, please add gaskets in time to solve the problem of reinstallation.
  8. Record information: flange connection information, make a detailed record of registration, to facilitate the later overhaul of the pipeline and maintenance work smoothly.
  9. Clean up the scene: the installation is completed, the site is cleaned up, the tools are stowed in place, and the garbage, to ensure that the site is clean.

Routine maintenance and upkeep of ANSI standard flanges

  1. Regularly inspect the flange connection to ensure that the bolts are tightened and the sealing gasket is not damaged. At the same time, check for any abnormal looseness or noise.
  2. Check the surface of the pipe body and flange for corrosion, and regularly perform anti-corrosion treatment on them.
  3. Ensure that the surrounding environment is clean and not covered by debris while keeping it dry and not in damp or water environments.
  4. Regularly apply lubricating oil to the flange.
  5. Regularly check the markings on the flange to ensure they are visible. If there is any damage, repair it promptly. Clear and visible markings can make maintenance and replacement more convenient in the future.
  6. It is necessary to make a detailed maintenance record form for easy reference.

Template of flange maintenance record form

NumberDateEquipment NameEquipment LocationMaintenance ContentMaintenance PersonnelRemarks
12024-01-10Electricity No. 210-351. Check that there is no leakage at the flange connection.
2. Clean the flange surface
3. Check for surface corrosion, wear, or damage, no damage, slight wear on the coating, clean and recoat.
4. Check if the bolts are loose and lubricate them with lubricant.
5. Check that the flange markings are clear and visible, the certification is valid, and maintenance is not required.
22024-02-11Electricity No. 312-211. Check that there is no leakage at the flange connection.
2. The flange pipeline is covered, and debris is cleaned to restore cleanliness and tidiness.
3. Check the surface for corrosion, wear, and damage.
Check if the bolts are loose and lubricate them with lubricant.
4. Check for blurred flange markings, query records, and replace them with new markings.
5. Upon inspection, it was found that the gasket was functioning properly and the seal was intact.
Template of flange maintenance record form

ANSI Flange Pressure Comparison Table

ANSI flange pressure value
ANSI Flange Pressure Comparison Table

What are the common flange standards besides ANSI flanges?

  1. European standard EN flange standards: EN 1092-1, EN 1759-1, EN 1514-1
  2. Chinese standard GB flange standards: GB/T 9112, GB/T 9123, GB/T 17241, GB/T 9113, GB/T 2506
  3. Japanese industrial standard JIS flange standards: JIS B2220, JIS B2291
  4. German industrial standard DIN flange standards: DIN 2573, DIN 2576, DIN 2633, DIN 2635, DIN 2642, DIN 2655
  5. British standard BS flange standards: BS 4504, BS EN 1092-1
  6. Australian standard AS flange standard: AS 2129

ASTM Standard Number and Material Cross Reference

ASTM Standard NumbersFlange Material
ASTM A105/A105NCarbon Steel
ASTM A350 LF2Low-Temperature Carbon Steel
ASTM A182 F304Stainless Steel 304
ASTM A182 F304LStainless Steel 304L
ASTM A182 F316Stainless Steel 316
ASTM A182 F316LStainless Steel 316L
ASTM A182 F321Stainless Steel F321
ASTM A182 F347Stainless Steel F347
ASTM A182 F11Alloy Steel
ASTM A182 F22Alloy Steel
ASTM A182 F9Alloy Steel
ASTM A182 F91High Temperature Alloy Steel
ASTM B564 N10276Corrosion Resistant Alloys
ASTM B564 N06625Corrosion Resistant Alloys
ASTM B564 N08825Corrosion Resistant Alloys
ASTM Standard Number and Material Cross Reference

ANSI flange standard can unify the flange specification size and thickness, to ensure that different manufacturers of flanges can be used interchangeably, improve the efficiency of the work, the later replacement of the maintenance is also more convenient, at the same time, strictly in line with the ANSI standard production of flanges, the quality of the flanges can be guaranteed, and more secure.

ANSI flange size is usually expressed in inches, ANSI flange size from 1/2 “to 60”, spanning a wide range of different sizes of pipes.

When choosing ANSI flange material, we should consider the working temperature, pipeline pressure, medium corrosivity, budget cost, and other aspects of the project to find the right material, if you have questions about the selection of materials, you can send an email to consult with us, we have professional engineers can give you detailed answers.

Yes, although ANSI is the American Standard flange, the international use of ANSI flange standards in many countries, especially in Europe and the United States, or the United States in other areas of the project will prefer ANSI flange.

The price of ANSI flange is a very sensitive issue, it is mainly affected by the cost of materials, specifications, size, pressure level, manufacturing process, manufacturer’s fees, labor costs and other factors, where there is no way to give a specific quote, if you have the need, please send us an email with your requirements, we will be the first time to give you a detailed breakdown of the price of ANSI flange quotes.

ANSI B16.5 is mainly for conventional flanges, the pressure level of Class150, Class300, Class400, Class600, Class900, Class1500, Class2500 and so on.
ANSI B16.47 is mainly for large flanges, of which the pressure classes commonly used in ANSI B16.47 Series A are Class150, Class300, Class400, Class600, Class900, Class1500. ANSI B16.47 Series B is usually suitable for lower pressure classes. The common ones are Class75, Class150, Class300, Class400, etc. 3.

The sealing face types of ANSI flanges include Flat Face Flange, Raised Face Flange, Tongue and Groove Flange, Ring Joint Flange, Chamfered Flange and Groove Flange.

ANSI flange bolt specification in the standard has detailed provisions, this can be in accordance with the ANSI flange standard implementation.

No, it is not recommended, because there are some differences between the flanges of different standards, and the interchangeability may cause various problems and lead to leakage.

To choose an experienced supplier, at the same time, we should consider whether the quality of ANSI standard flanges they provide is guaranteed, whether the price is reasonable, whether the delivery time is suitable, whether the transportation is convenient, whether there is after-sales service and other factors, and then make a comprehensive assessment to find out the flange manufacturers who are better, and we recommend the Chinese flange manufacturers here because the manufacturing industry is more developed in China, and the made-in-China stands for high-quality and low-priced. price, similarly the flanges we produce are of high quality but cheaper, so it is a very good choice.