According to ASME B31.3 Power piping code, what is the maximum diameter for slip-on flanges to be used for boiler external piping?

In accordance with the ASME B31.3 Power Piping Code, the maximum diameter for slip-on flanges used in boiler external piping is indeed 4 inches. This specification is important because slip-on flanges are designed for lower pressure applications, and their use is limited in size to ensure that they maintain structural integrity and are suited for the expected operating conditions.

When it comes to boiler external piping, ensuring the proper diameter of components helps in maintaining the safety and functionality of the piping system. Larger sizes may not perform reliably under the stress and conditions typical of boiler operations, hence the restriction at 4 inches.

The guidelines established in the ASME B31.3 ensure that all components, including slip-on flanges, are appropriately sized and suited for their function within the system, particularly in critical applications like boilers where failure can lead to significant hazards.