Elite Piping Manufacture produces high-quality ANSI B16.47 flange with reliable quality and excellent performance, which has played a huge role in industrial construction development.
There are two series of ANSI B16.47 flanges: A series and B series. There is also an ANSI B16.5 standard number for ANSI flanges. Generally speaking, the flange size of B16.5 is less than 24 inches, and the flange size of B16.47 is larger than 24 inches.
B16.47 A series is the name obtained after the MSS SP44 standard flange joins the ANSI flange system, while the B series is obtained after the API 605 standard flange joins the ANSI flange system. This relationship is between MSS SP44, API 605 flange, and ANSI B16.47.
The Advantages Of ANSI B16.47 Flange
When choosing American standard flanges, it is crucial to consider opting for larger diameter flanges if the large diameter is greater than DN600. National standard flanges are generally selected according to HG/T 20623-2009 specification. ASME flanges are selected according to ASME B16.47-2020.
It is often encountered that designers select large-diameter flange models but do not mark whether the flange is per the A series or the B series, which eventually leads to purchasing the wrong flange, resulting in huge economic losses.
For Class 150 and 300 and NPS 36 or smaller sizes, API 605 and MSS SP-44 flanges are incompatible and cannot be paired.
For easy distinction, MSS SP-44 flanges are designated as A series. API 605 flanges are designated as B series.
B series flanges require more but smaller fasteners (bolts and nuts) than A series flanges, and the bolt center circle diameter is smaller than that of A series flanges.
Both A series and B series define raised face (RF) butt welding flanges and flange covers, but only the A series has ring joint (RJ) flanges from Class300 to Class900.
The pipe sizes of A series and B series are completely different. For example, the outer diameter of the A series pipe of DN650-Class150 is 660.4, and that of the B series is 661.9.
It is more noteworthy that the outer diameter of the A series’s flange welding end (the pipe’s outer diameter) has nothing to do with the pressure level, while the outer diameter of the flange welding end of the B series is different for each pressure level.
The Applications Of ANSI B16.47 Flange
Generally, the owner will give the ANSI B16.47 flange requirements of A series or B series, which can be agreed upon by the owner or contract.
Because the A series ANSI B16.47 flange has large redundancy, uniform pipe size, and an additional RJ sealing surface, most pipeline users or designers may choose A series flanges for new pipes or equipment.
The B series ANSI B16.47 flange offers an affordable and compact solution， or the previous device used API 605, which was renovated or replaced, or the flange or manhole of the equipment itself; using the B series can save construction costs.
Of course, the B series is not cheaper than the A series in all cases. For example, for Class 300, which is larger than DN 950, the B series flange is heavier than the A series.
Not all high-pressure grades are heavier than low-pressure grades. For example, the weight of A series DN 950, Class 150, is 326.9kg, and that of Class 300 is 315.6kg.
Not all large diameters are heavier than small diameters. For example, the weight of DN900 of Class 300 of A series is 578.9kg, and that of DN950 is 315.6kg. The weight of DN650 of Class 150 and B series is 54.5kg, and that of DN600 WN pipe flange is 121.7kg.
The above is an introduction to the ANSI B16.47 flange. If you have any other questions, please feel free to contact us.
