ASME B16.5 VS ASME B16.47

ASME B16.5 and ASME B16.47 are both producing standards of flanges for the size and pressure rating difference .The differs contain: The main difference between ASME B16.5 and ASME B16.47 is that they cover different flange size ranges.

Summary of flange sizes specified by ASME B16.5 and B16.47 standards:

Notes:

1. MSS SP-44 flanges are designated Series A flanges in ASME B16.47.It also covers flanges in the range NPS 12 to 24,
   these being equivalent to ASME B16.5 flanges in the same range (except for the addition of NPS 22 in MSS SP-44).

2. API 605 has been cancelled. API 605 flanges are designated Series B flanges in ASME B16.47. Ranges quoted are based on ASME B16.47 Series B.

3. Dimensions not covered in this summary

   
   

ASME B16.5 Size Range

The nominal size range is relatively wide, from NPS 1/2 (about 15mm) to NPS 24 (about 600mm). This size range can meet the needs of most conventional piping systems, whether it is a small industrial device or a general-sized pipeline transportation system, you can find a flange of the right size.

ASME B16.47 Size Range

As mentioned earlier, its nominal size ranges from NPS 26 (about 660mm) to NPS 60 (about 1524mm), specifically for large diameter pipes.

ASME B16.5 Pressure Level

The pressure level ranges from Class 150 (about 2.0MPa) to Class 2500 (about 42.0MPa), covering different pressure ranges such as low, medium and high pressure. Different pressure levels correspond to different flange thicknesses, bolt specifications and sealing requirements to ensure reliable sealing and connection under the corresponding working pressure.

ASME B16.47 Pressure Level

The pressure level ranges from Class 75 (about 1.3MPa) to Class 900 (about 15.0MPa). Compared with the ASME B16.5 standard, its pressure level range is different and focuses more on the application of large diameter pipes under medium and low pressure conditions.

The flange types produced by ASME B16.5 and ASME B16.47 are different.

The ASME B16.5 standard includes flange types:

Butt welded flange (WN FLANGE),

Flat welded flange (SO FLANGE),

Socket flange (SW FLANGE),

Threaded flange (TH FLANGE),

Blind flange (BL FLANGE),

Loose flange (LAPJ FLANGE).

The ASME B16.47 standard includes flange types: butt welded flange (WN FLANGE) and blind flange (BL FALNGE).

The ASME B16.47 standard is also divided into series A and series B.

The A series specifies the flange size for ordinary flanges, while the B series specifies the flange size for compact flanges.

The diameter of bolt holes on A series flanges is larger than that on B series flanges, and the number of bolt holes is less than that on B series flanges. The size of bolt holes of the B series flange are smaller than those of the A series flange, and the number of bolt holes is more than that of the A series flange.

ASME B16 47 Series A flanges are thicker, heavier, and stronger than their Series B counterparts. They also can often handle more external loading than Series B. Series A flanges tend to be more costly than Series B flanges.

ASME B16.47 Series B flanges need more but smaller fasteners, such as bolts & nuts. They also usually have a smaller bolt circle diameter than Series A flanges. Generally, there is less flange movement after installation due to the smaller bolt circle diameter.

Both Series A and B define weld neck flanges and blind flanges in raised face type. However, Series A defines ring-type joint (RTJ) flanges from Class 300 through Class 900 within this standard while Series B does not.

Series A flanges are popular for new pipeline projects or equipment. Meanwhile, many choose Series B flanges for refurbishment or replacement jobs.

Whichever choosing ASME B16.5 standard flanges or ASME B16.47 standard flanges, it is necessary to confirm the exact producing standard based on the specific application of the pipeline system.