Flange Standards Comparison – ASME, EN, DIN, JIS & BS

Flanges are manufactured according to different international dimensional and technical standards depending on the piping system, equipment design, project specification and country of application.

The most commonly encountered flange standards include ASME, EN, DIN, JIS and BS. Although these standards serve similar connection purposes, their dimensions, pressure designations, bolt patterns, facing arrangements and other requirements can differ.

Understanding the applicable standard is important before ordering or replacing a flange.

ASME Flanges

ASME flange standards are widely used in oil & gas, petrochemical, chemical, power generation, process industries and industrial piping systems.

Commonly referenced standards include:

ASME B16.5 – Pipe Flanges and Flanged Fittings for commonly used flange sizes.

ASME B16.47 – Large Diameter Steel Flanges.

ASME flange pressure classes commonly include:

• Class 150

• Class 300

• Class 400

• Class 600

• Class 900

• Class 1500

• Class 2500

Applicable pressure classes and flange configurations depend on the relevant standard and size.

EN Flanges

EN 1092-1 is widely used for steel flanges in European-standard piping applications.

EN flanges commonly use PN pressure designations, such as:

• PN6

• PN10

• PN16

• PN25

• PN40

• PN63

• PN100

• PN160

The actual flange dimensions and configuration depend on the applicable type, DN size, PN rating and material requirements.

DIN Flanges

DIN flange specifications are associated with German standards and are still encountered in existing equipment, machinery, piping systems and replacement requirements.

Customers may request DIN flanges based on a specific DIN designation, size, pressure requirement and flange type.

For replacement applications, the exact standard and dimensions should always be confirmed rather than assuming that a DIN flange is interchangeable with an EN flange.

JIS Flanges

JIS flanges are commonly used in Japanese-designed equipment and piping systems and are also found in various international industrial projects.

JIS flange requirements may use pressure designations such as:

• 5K

• 10K

• 16K

• 20K

• 30K

• Other applicable ratings depending on the standard

JIS flange dimensions, bolt-hole patterns and facing arrangements can differ from ASME and EN flange systems.

BS Flanges

BS flange standards may be encountered in older installations, replacement requirements and projects based on British standards.

When supplying replacement BS flanges, the original standard designation and dimensional requirements should be checked carefully.

This is particularly important for existing piping systems where the original components may have been manufactured to an older specification.

ASME vs EN Flanges

ASME and EN flanges are both widely used internationally, but their dimensional systems are different.

Some important differences can include:

Pressure designation:
ASME generally uses Class ratings, while EN commonly uses PN ratings.

Dimensions:
Outside diameter, thickness, bolt-circle diameter, bolt-hole size and other dimensions may differ.

Bolt patterns:
The number and arrangement of bolt holes can vary between standards.

Facing:
Facing configurations and dimensions should be checked according to the applicable standard.

Because of these differences, an ASME flange should not automatically be considered a direct dimensional replacement for an EN flange.

DIN vs EN Flanges

DIN and EN standards can be encountered together in European piping applications, particularly in existing installations.

However, the exact standard designation should be confirmed before ordering.

For replacement requirements, customers should provide the original flange marking, drawing, dimensions or equipment specification whenever possible.

JIS vs ASME Flanges

JIS and ASME flange systems can differ in:

• Outside diameter

• Thickness

• Bolt-hole arrangement

• PCD

• Bolt-hole diameter

• Pressure designation

• Facing configuration

A JIS flange should therefore not be selected as an ASME replacement based only on nominal pipe size.

BS vs ASME Flanges

BS and ASME flange dimensions may not match even when the nominal pipe size appears similar.

For replacement applications, the following should be checked:

• Standard

• Nominal size

• Pressure rating

• Flange type

• Facing

• PCD

• Number of holes

• Hole diameter

• Thickness

• Bore

Why Flange Standard Identification Matters

Incorrect standard selection can result in problems during installation.

Before placing an order, confirm:

Flange Standard
Nominal Size / DN / NPS
Pressure Class or PN Rating
Flange Type
Facing
Material Grade
Bore / Schedule
Quantity

For a replacement flange, dimensional verification is especially important.

Flange Types Available Across Different Standards

Depending on the applicable standard, project and size requirements, flange configurations may include:

• Weld Neck Flanges

• Blind Flanges

• Slip-On Flanges

• Socket Weld Flanges

• Threaded Flanges

• Lap Joint Flanges

• Orifice Flanges

• Long Weld Neck Flanges

• Plate Flanges

• Special Flanges

Not every flange type, size or pressure rating is available under every standard. The applicable standard should therefore be confirmed before manufacturing or supply.

Flange Materials

Flanges manufactured to different standards can be supplied in a variety of materials, depending on the applicable specification.

Common materials include:

• Carbon Steel

• Stainless Steel

• Duplex Stainless Steel

• Super Duplex Stainless Steel

• Alloy Steel

• Nickel Alloys

• Nickel-Copper Alloys

• High Temperature Alloys

• Titanium and other special materials

Commonly requested grades include A105, F304, F304L, F316, F316L, F321, F347, F310, F904L, Duplex 2205, Super Duplex 2507, Monel, Inconel, Incoloy and Hastelloy grades.

Flange Replacement – What Information Is Required?

When replacing an existing flange, the safest approach is to identify the original specification rather than selecting a flange only by pipe size.

Useful information includes:

• Existing flange marking

• Standard

• Size

• Pressure rating

• Material

• Flange type

• Facing

• Outside diameter

• Thickness

• Bore

• PCD

• Number of bolt holes

• Bolt-hole diameter

• Drawing or photograph

For special or obsolete flanges, a dimensional drawing or sample can help in evaluating the replacement requirement.

Inspection & Documentation

Depending on the purchase specification, flange inspection and documentation may include:

• Dimensional inspection

• Visual inspection

• Material identification

• Chemical test documentation

• Mechanical test documentation

• Heat treatment records where applicable

• EN 10204 Type 3.1 MTC

• Third-party inspection

• Marking and traceability

The required documentation should be confirmed at the quotation or purchase stage.

Vandan Alloys – Multi-Standard Flange Supplier

Vandan Alloys manufactures and supplies industrial flanges for customers requiring different international standards and project specifications.

Our supply capability covers requirements involving:

ASME / ANSI Flanges
EN Flanges
DIN Flanges
JIS Flanges
BS Flanges
Custom & Drawing-Based Flanges

We supply flanges in different materials, sizes, pressure classes, PN ratings and configurations according to the applicable requirements.

How to Select the Correct Flange Standard

The correct flange should be selected based on the complete piping or equipment requirement rather than nominal size alone.

Before ordering, confirm the:

Standard + Size + Rating + Type + Facing + Material + Bore + Quantity

For replacement or custom requirements, providing the original drawing, flange marking or dimensional details can help avoid dimensional mismatch.

Worldwide Flange Supply from India

Vandan Alloys supports domestic and international requirements for industrial flanges and related piping components.

We cater to customers looking for ASME flange manufacturers in India, EN flange suppliers, DIN flange suppliers, JIS flange manufacturers, BS flange suppliers and custom flange exporters from India.

Send your flange standard, drawing or specification to Vandan Alloys for quotation.

Vandan Alloys 

Manufacturer of All Types of Flanges

3/5, Sakar Bhavan, Ground Floor, 6th  Khetwadi lane, SVP Road ,Mumbai – 400 004. India

TEL+91 022 6610 9925Mobile no: 09892882255  GSTIN:  27AUMPS2067F1ZB

Email: info@vandanalloys.com ; Web: www.vandanalloys.com

Please visit Our Flanges Division:www.vandanalloys.net

SEO Title

Flange Standards Comparison – ASME, EN, DIN, JIS & BS | Vandan Alloys

Meta Description

Compare ASME, EN, DIN, JIS and BS flange standards. Learn about pressure ratings, dimensions, flange types, materials and selection for replacement and industrial piping.

SEO Keywords

flange standards comparison, ASME flange manufacturer India, EN flange manufacturer India, DIN flange supplier India, JIS flange manufacturer India, BS flange supplier India, ASME vs EN flange, DIN vs EN flange, JIS flange supplier, BS flange manufacturer, international flange standards, ASME B16.5 flange, ASME B16.47 flange, EN 1092-1 flange, industrial flange manufacturer India, flange exporter India, multi standard flange supplier, custom flange manufacturer India, flange replacement supplier, flange manufacturer Mumbai