What are the ASME/ANSI standards for weld neck flanges？

Many places in industry use welding neck flanges as an important part of pipe systems because welding neck flanges keep connections safe and sound. The American National Standards Institute (ANSI) and the American Society of Mechanical Engineers (ASME) have rules that these bands must follow. If you do these things, your pipes will be safe, work well, and follow the rules. We'll talk about the main ASME/ANSI rules for welding neck flanges in this in-depth help. We'll also talk about their sizes, grades, and important things you should understand before you buy and use welding neck flanges. Weld neck flanges are mostly governed by ASME B16.5 and ASME B16.47. Because of these rules, flanges should be made of certain materials and have certain sizes and weights. They should also be marked in a certain way. Some flanges are made for pipes with a diameter of up to 24 inches, and others are made for pipes with a diameter of 26 inches to 60 inches. Items from different brands must follow these rules in order to be used together and maintain their functionality. Because of this, builders, workers, and people who buy things in the pipe business need them.

welding neck flanges

Which ASME and ANSI standards specify welding neck flange dimensions and ratings?

There are two main rules that say welding neck plates need to be a certain size and grade:

ASME B16.5

The standard most often used for pipe flanges and flanged valves is ASME B16.5. In it are:

Sizes of pipes range from 1/2 inch to 24 inches (NPS).
Types of pressure from 150 to 2500
Carbon steel, special steel, and stainless steel are some of the materials used.
It can be anywhere from -20°F to 1500°F.

This rule tells you the exact sizes of slip-on flanges, welding neck flanges, and lap joint flanges, among others.

ASME B16.47

A16.47 from ASME adds to B16.5 by covering flanges with a larger diameter:

Pipes range in length from 26 to 60 inches (NPS).
There are 75 to 900 kPa of pressure.
A (MSS SP-44) and B (API 605) are the two types of flanges.

Face-to-face measurements, bolt circle sizes, and hub dimensions are all important pieces of information that are given in both standards for choosing and defining welding neck flanges.

Overview of ASME B16.5 and B16.47 classifications for weld neck flanges

ASME B16.5 Classifications

Weld neck flanges are put into groups by ASME B16.5 based on a few important factors:

Pressure Class: This number ranges from 150 to 2500 and shows the highest pressure that can be used at room temperature.
Material Group: Grouped by the qualities of the material and the amount of force that can be applied to it.
There are three types of flange faces: raised face, flat face, and ring-type joint (RTJ).
hole: Any standard hole or a special bore that fits the inside diameter of the pipe

For each pressure class, the standard gives thorough lists with measurements like outside diameter, hub diameter, and bolt hole designs.

ASME B16.47 Classifications

ASME B16.47 adds two types to B16.5 that are for flanges with a wider width.

Series A (MSS SP-44): Sizes from 26" to 60" and pressure levels from 75 to 900
Series B (API 605): Sizes range from 26" to 60" and pressure levels from 75 to 900, but the dimensions must be met in a different way.

Which one to choose between Series A and B rests on the needs of the business and how well they work with other systems.

Key Differences

They both talk about welding neck flanges, but they are different in important ways:

The pressure classes for B16.5 are higher for smaller sizes, going up to 2500.
B16.47 has two series choices for bigger sizes, which gives designers more freedom in their designs.
For theoretical widths that are the same, the two standards may have different bolt shapes and lip thicknesses.

Pressure classes, materials, and marking requirements under ASME standards

Pressure Classes

ASME rules say that the following types of pressure can be used to weld neck flanges:

The ranges of strength in ASME B16.5 are 150, 300, 400, 600, 900, 1500, and 2500.
That's what ASME B16.47 says: 75, 150, 300, 400, 600, and 900.

When everything is okay, the highest pressure in each class is 100°F (38°C).

Materials

Different kinds of materials can be used to make weld neck plates, according to ASME rules.

There are different kinds of iron and steel, like ASTM A105, A350 LF2, and ASTM A182 F304, F316, and F321.
Steels and alloys made from zinc metals that meet ASTM A182 F11, F22, and F91 standards

Before you buy something, find out how strong it is, how long it will last, and how it will work in different weather.

Marking Requirements

ASME guidelines say that welding neck flanges must be marked in a certain way so that they can be found and tracked:

Name or brand of the person who made it
Brand name of the material (like A105 or F316)
Rate of pressure class (20, 300, etc.)
The size of the pipe that is supposed to fit
What does the ASME standard (B16.5 or B16.47) stand for?
To track down materials, use a heat number or lot number.

Usually, these numbers are stamped or carved on the edge of the lip or on the high hub area.

Additional Considerations

When following ASME guidelines to choose and define welding neck flanges, think about:

A temperature derating means that pressure numbers drop as temperatures rise.
Check to see if the type of flange face you want to use will work with the cover you want to use.
Corrosion allowance: Think about how much stuff you could lose over time in salty places.
As an important note, for some uses, you may need more than what ASME requires, like testing or a license.

By following these ASME/ANSI standards and thinking about all the important things, engineers and people who work in buying can make sure that pipe systems with welding neck flanges are safe, reliable, and work well.

Conclusion

A lot of different types of businesses need to know the ASME/ANSI rules for welding neck flanges to make sure their pipe systems are safe, work well, and follow the rules. Engineers and buying workers can use these standards to make smart choices about which flanges to buy by giving them detailed information about their sizes, pressure levels, materials, and marking needs.

HEBEI RAYOUNG PIPELINE TECHNOLOGY CO., LTD is the only place you need to go for welding neck flanges that meet or go beyond ASME/ANSI standards. We are one of the biggest companies that make industrial pipe fittings, and we have a lot of different goods, like carbon steel pipe fittings, that can be used for a lot of different projects. Our dedication to quality is shown by our ISO 9001:2015 certification as well as our GOST-R and SGS export certificates.

You can work with RAYOUNG as an EPC contractor on big industrial projects, as a reseller looking for dependable providers, or as an end-user wanting long-term safety and performance. We have the knowledge and products to meet your needs. Our welding neck flanges are made to reduce project risk, ensure compliance, and provide the same high quality in all situations.

FAQ

1. What are the main differences between ASME B16.5 and ASME B16.47 standards for welding neck flanges?

The major differences are the types of forces and sizes that they can take. ASME B16.5 says that pressures of up to 2500 PSI can be put on flanges that are 1/2" to 24" NPS. ASME B16.47 says that flanges that are at least 26" to 60" NPS can handle pressure of up to 900 PSI. The B16.47 comes in two different types: A and B. These need to be a little different sizes.

2. How do I choose the right pressure class for my welding neck flange?

To choose the correct pressure class, you should think about the largest temperature and pressure that your device can handle. It is best to choose a pressure class that is higher than the worst conditions you can work in. You should also think about how the pressure or temperature might change. Always look at the ASME rules for a material to find out what its pressure-temperature limits are.

3. What information should be included in the marking of a welding neck flange according to ASME standards?

Welding neck flanges must have a mark that says the name of the material, the usual pipe size (NPS), the name of the ASME standard (B16.5 or B16.47), the name of the person or company that made them, and either a heat number or a lot number. This helps you find the stuff more easily.

Expert Welding Neck Flanges for Your Industrial Piping Needs | RAYOUNG

You can get stable and good welding neck flanges from HEBEI RAYOUNG PIPELINE TECHNOLOGY CO., LTD. for your pipe systems. You can be sure to find the right ASME/ANSI-approved flange for your job because we have a lot of them.

If you use cheap parts on your lines, make sure that they don't become less effective. For better welding neck flanges that last a long time and give you peace of mind, choose RAYOUNG. Contact us today at info@hb-steel.com to discuss your needs and receive expert guidance on selecting the right flanges for your application. Let RAYOUNG be your partner in building safe, efficient, and compliant industrial piping systems.

References

1. American Society of Mechanical Engineers. (2017). ASME B16.5-2017: Pipe Flanges and Flanged Fittings NPS 1/2 Through NPS 24 Metric/Inch Standard.

2. American Society of Mechanical Engineers. (2016). ASME B16.47-2016: Large Diameter Steel Flanges: NPS 26 Through NPS 60 Metric/Inch Standard.

3. Nayyar, M. L. (2000). Piping Handbook (7th ed.). McGraw-Hill Education.

4. American Petroleum Institute. (2015). API Standard 605: Large-Diameter Carbon Steel Flanges.

5. Smith, P., & Zappe, R. W. (2004). Valve Selection Handbook: Engineering Fundamentals for Selecting the Right Valve Design for Every Industrial Flow Application (5th ed.). Gulf Professional Publishing.

6. Manufacturers Standardization Society. (2016). MSS SP-44: Steel Pipeline Flanges.