What is ASME B16.47 sandard ?
ASME B16.47 is the primary standard for large diameter steel flanges (NPS 26" to 60"). It defines two non-interchangeable series: Series A (MSS SP-44) and Series B (API 605), which result in their critical differences in dimensions, performance, and application scenarios.
ASME B16.47 Series A is derived from MSS SP-44 standard. It is belong to heavier, thicker, and higher strength industrial purpose flange.
ASME B16.47 Series B is derived from API 605 standard. It is belong to lighter, more compact, and cost-effective flange.
Note: Series A and Series B are not interchangeable due to mismatched bolt circle diameter (BCD), outside diameter, and thickness.
Core Dimensional Differences (NPS 36", Class 150 Example)
|
Parameter |
Series A (MSS SP-44) |
Series B (API 605) |
|
Flange outside diameter (OD) |
Larger OD (1168mm) |
Smaller OD (1057mm) |
|
Bolt circle diameter (BCD) |
Larger (1085.8mm) |
Smaller (1009.6mm) |
|
Number of bolt hole |
Fewer (32) |
More (44) |
|
Bolt hole diameter |
1-5/8" |
1" |
|
Thickness and Weight |
Thicker and Heavier |
Thinner and Lighter |
Pressure rating and seal face type
Series A: Class 150, Class 300, Class 400, Class 600, Class 900. The seal face type Includes Raised face (RF) and Ring Type Joint (RTJ) facings. It is suitable for high-pressure and strong vibration working scenarios.
Series B: Class 75, Class 150, Class 300, Class 400, Class 600, Class 900. The seal face type only include Raised Face (RF). It is suitable for low and medium pressure pipeline systems.
Typical application
Series A flanges are specially designed for high-pressure, strong vibration environments where safety and long-term performance are paramount. Typical applications include:
a. Oil and gas industry: High pressure oil and natural gas transmission pipelines (onshore and offshore), refinery hydrocracking unit,, and offshore drilling platforms.
b. Power generation: Nuclear power plants, thermal power plants, and renewable energy facilities. These applications require flanges that can withstand extreme high-temperature and high-pressure without failure.
Series B flanges are ideal for applications where performance requirements are moderate. Typical applications include:
a. General industrial applications: Low and medium pressure pipeline systems. These applications do not require extreme pressure or temperature resistance, making Series B a cost-effective choice.
b. Energy industry: In the pipeline systems of energy projects such as large steam pipelines, Series B flanges are used to connect large diameter pipelines to ensure safe and stable operation of the system under high-pressure.
ASME B16.47 large diameter welded neck and blind flange can be supplied by us. They are available in multiple materials, such as carbon steel, stainless steel, and alloy steel, etc. We have flexible supply capacity, small order and trial order can be accepted. The delivery is very fast. If you are interested in our flanges, welcome to visit our website for more details.
