Flanges for US industries
The same forged flanges go into a Gulf Coast refinery, a Midwest water plant and a Virginia data center. What changes is the code, the class and the grade. Here is what each US industry usually specifies.
We make forged stainless steel and carbon steel flanges to ASME B16.5, B16.47 and B16.36 and AWWA C207 and C228 for US industry: oil and gas, refining and petrochemical, chemical processing, power generation, water and wastewater, pharmaceutical, food and beverage, HVAC and district energy, shipbuilding and offshore, and data centers. Every line is supplied to your line list from our works in Gujarat, India, and every heat ships with an EN 10204 3.1 mill test report.
What each industry specifies
| Industry | Piping code | Usual flanges | Usual grades |
|---|---|---|---|
| Oil and gas | ASME B31.4, B31.8 | Weld neck, blind and RTJ, Class 300 to 2500 | A105, A350 LF2, A694 F42 to F70 |
| Refining and petrochemical | ASME B31.3 | Weld neck, RTJ, orifice, spectacle blinds | A105, LF2, 316L, 321, 347, duplex |
| Chemical processing | ASME B31.3 | Weld neck, lap joint with stub ends | 316L, 904L, duplex, super duplex |
| Power generation | ASME B31.1 | Weld neck, Class 600 to 2500 on steam and feedwater | A105, alloy grade per spec |
| Water and wastewater | AWWA standards; ASME B31.3 in plants | AWWA C207 and C228; flat face at pumps | Carbon steel, 304L, 316L |
| Pharmaceutical and biotech | ASME B31.3 for utilities | Weld neck and long weld neck nozzles | 316L, 304L, passivated |
| Food and beverage | ASME B31.5 for ammonia refrigeration | Weld neck and socket weld | A105, A350 LF2, 304L, 316L |
| HVAC and district energy | ASME B31.9, B31.1 | Class 150 weld neck, slip-on, flat face | A105 |
| Shipbuilding and offshore | Classification society rules | Weld neck, socket weld, RTJ | Duplex, super duplex, 316L, A105 |
| Data centers | ASME B31.9, B31.3 | Class 150 weld neck, slip-on, lap joint | A105, 304L, 316L |
Industry pages
Oil and gas
Weld neck, blind and RTJ flanges in A105, LF2 and A694 high yield for pipelines and stations.
Refining and petrochemical
Weld neck, RTJ, orifice flanges and spectacle blinds to ASME B31.3, with PMI on every alloy flange.
Power generation
Weld neck flanges for steam, feedwater and cooling water to ASME B31.1, Class 150 to 2500.
Water and wastewater
AWWA C207 and C228 flanges for mains, ASME B16.5 and flat face flanges for the plant.
Chemical processing
Stainless, 904L, duplex and super duplex flanges for corrosive process piping.
Pharmaceutical and biotech
316L and 304L flanges for clean utilities and process support, documented for validation.
Food and beverage
Stainless flanges for wash-down utilities, LF2 and A105 for ammonia refrigeration.
HVAC and district energy
Class 150 weld neck, slip-on and flat face flanges for chilled, condenser and hot water.
Shipbuilding and offshore
Duplex and super duplex flanges qualified to NORSOK M-650, plus 316L and carbon steel.
Data center cooling piping: where flanges are used
How flange material, standard and face change along data center cooling piping, from cooling towers and chillers to liquid cooling CDUs and the TCS loop.
Flange types for process and pipeline work
Beyond the weld neck, slip-on, blind and lap joint flanges used everywhere, process plants and pipelines call for types with their own standards and ordering details:
High pressure flanges
ASME B16.5 Class 600, 900, 1500 and 2500, with ratings, sizes and RTJ facing.
Ring type joint flanges
RTJ grooves to ASME B16.5 for R and RX ring gaskets, Class 150 to 2500.
Orifice flanges
ASME B16.36 weld neck, slip-on and threaded, with pressure taps, Class 300 to 2500.
Spectacle blinds
Figure-8 blinds, paddle blanks and spacers to ASME B16.48, Class 150 to 900.
Socket weld flanges
NPS 1/2 to 3 for small-bore process and utility lines, bored to the pipe schedule.
Threaded flanges
NPT threads to ASME B1.20.1 for utility, small-bore and no-weld connections.
Long weld neck flanges
One-piece flange and nozzle for vessels and exchangers, neck to your drawing.
Flange bolt chart
Stud bolt count, diameter and length for ASME B16.5 Class 150 to 2500, raised face and RTJ.
What every order includes
- An EN 10204 3.1 mill test report for every heat, with chemistry, mechanical tests and heat treatment; EN 10204 3.2 with your inspector or a third-party agency.
- Each flange stamped with grade, standard, size, class and heat number, so it traces back to its report.
- Positive material identification on every stainless and alloy flange, recorded on the certificate.
- Export packing in wooden cases, with the packing list by line item.
Our quality system is certified to ISO 9001:2015 by TÜV NORD and to ISO 29001:2020, the quality management standard for the petroleum, petrochemical and natural gas industries, by Gulf Lloyds Business Assurance. See quality and traceability.
Texas and the Gulf Coast
Houston and the Texas Gulf Coast are where most US oil and gas, refining and petrochemical piping is designed and built. Our Texas page covers what Texas projects specify and how shipments reach them through Port Houston.
Indian companies named on the industry pages are RIC customers listed on our main website. US codes and standards are named to describe what each industry specifies.