The ASME B16.5 Class 2500 Blind Flange's primary job is to seal off the end of a piping system or a pressure vessel opening. Because Class 2500 represents the "heavyweight" category, these flanges are significantly thicker and heavier than their Class 150 or 300 counterparts. HT PIPE supply all different types and scales of flanges. Please feel free to contact us for further product information and pricing.
Material and Facing Requirements
In Class 2500 applications, the material choice is as vital as the dimensions. Common specifications include:
- ASTM A105: Carbon steel for ambient to high-temperature service.
- ASTM A182: Forged stainless steel (F304/F316) or alloy steels for corrosive environments.
The Ring Type Joint (RTJ): While many flanges use a Raised Face, Class 2500 systems frequently utilize Ring Type Joint (RTJ) facings. In these cases, a groove is machined into the flange face to hold a metal ring gasket. This creates a "metal-to-metal" seal that is far more resilient under extreme pressure than standard flat gaskets.
ASME B16.5 Class 2500 Blind Flange Dimensions
FAQ
Q: When should I choose RTJ over RF for Class 2500?
While Raised Face (RF) is common, Ring Type Joint (RTJ) is the preferred standard for Class 2500 in the oil and gas industry. RTJ is recommended for:
- High-temperature cycles where thermal expansion occurs.
- High-vibration environments.
- Applications involving hazardous or lethal gases where a "metal-to-metal" seal is required for safety.
Q: Are Class 2500 blind flanges available in sizes larger than 12"?
ASME B16.5 technically covers flanges up to NPS 24; however, Class 2500 is only standardized up to NPS 12 within the B16.5 volume. For sizes larger than 12" at this pressure rating, engineers must typically refer to ASME B16.47 Series A or B, or move toward custom-engineered "Project Specific" drawings.
