AWWA Class B to API 6BX 20K
Piping Flanges Across the
Full Pressure Spectrum
A reference for the full pressure range. Class 125LW lightweight for waterworks, ASME B16.5 through Class 2500 for industrial process, and API 6A and 6BX up to 20,000 psi for wellhead service. Carbon, stainless, alloy, and exotic material families covered in one place.
The Spectrum
One Source, Every Class
Lightweight
86 - 300 PSI
Class 125LW, AWWA C207 B/D/E/F. Waterworks, cooling loops, large diameter up to 144".
Standard
150 - 600 Class
ASME B16.5 and B16.47. The industrial workhorse range. Process piping, refining, utilities.
High Pressure
900 - 2500 Class
Heavy-wall ASME for steam, high-temp hydrocarbon, and critical service.
API Service
2K - 20K PSI
API 6A and 6BX for wellhead, BOP, and drilling. RTJ facings with proper ring gaskets.
7
Pressure Classes Covered
AWWA + ASME + API
Standards Referenced
Same Day
Quote Turnaround
Since 1986
Texas Flange Reference
What We Supply
Three Product Categories. Thousands of Configurations.
Every piece traceable, tested, and ready to install. From a single blind for a maintenance shutdown to a full BOM for new construction.
Flanges
Weld neck, blind, slip-on, threaded, socket weld, lap joint, reducing, orifice, spectacle blind, plate, long weld neck. 1/2" to 144" NPS. Class 125LW through 2500.
- ✓ASME B16.5 & B16.47
- ✓AWWA C207 & C228
- ✓API 6A & 6BX
- ✓DIN & EN 1092-1
Pipe Fittings
Elbows, tees, reducers, caps, couplings, unions, and specialty fittings. Butt-weld, socket-weld, and threaded for every service condition.
- ✓ASME B16.9 & B16.11
- ✓Schedule 10 through XXH
- ✓Seamless & welded
- ✓Hot induction bends
Custom Machining
Non-standard bores, overbore flanges, special facings, and tight-tolerance work covered through the Texas Flange machining program. Drawings or specs both work.
- ✓Fast turnaround on non-standard work
- ✓Ring-type joint grooves
- ✓Specialty facings and bore work
- ✓Full MTR documentation
Standards & Compliance
Built to Code. Documented.
Every flange ships with full material traceability and dimensional verification against the standard it was ordered to. No gray areas.
ASME B16.5
Pipe Flanges 1/2" - 24"
ASME B16.47
Large Diameter 26" - 60"
AWWA C207
Steel Pipe Flanges 4" - 144"
API 6A / 6BX
Wellhead & Drilling Equipment
ANSI B16.1
Cast Iron Class 125, 250
DIN / EN 1092
European PN 6 - PN 400
MSS SP-44
High Yield F42 - F70
NACE MR0175
Sour Service Materials
Reference Coverage
What This Resource Covers
Full Pressure Range
Most flange references cover one slice of the curve. This one covers AWWA Class B at 86 psi through API 6BX 20K, so a project that crosses pressure ranges does not have to cross multiple reference sites.
Material Traceability
Mill test reports traceable to the heat number are standard on flange orders. EN 10204 3.1 and 3.2 certificates are documented as part of normal procurement practice for industrial piping.
Pressure-Temperature Context
Class is not pressure. The standards reference pages cross-reference class to derated pressure at service temperature using ASME B16.5 Table 2, so spec selection lines up with duty.
Domestic and Import Background
Buy American and ARRA documentation requirements are explained alongside imported material options. Either path is covered in the standards reference content.
Specialty Metallurgy
Duplex, super duplex, Inconel, Monel, Hastelloy, chrome-moly, and high yield carbon are all covered in the materials section, with notes on where each one earns its premium.
Custom and Non-Standard
Overbore, special facings, RTJ grooves, and weld overlay sit outside the standard catalog. The custom machining page covers what falls into that category.
Sectors We Serve
From Wellhead to Water Main
Different industries, different specs, same standard of execution.
Technical Resources
Engineering Reference
Spec sheets are fine. Understanding why the spec matters is better. These guides help your team make faster, more confident decisions.
Flange Types Guide
Weld neck vs. slip-on vs. blind. Application criteria, pros and cons.
Access Resource →
Pressure-Temperature Ratings
ASME B16.5 P-T tables for common materials. How class translates to PSI at temperature.
Access Resource →
Bolt Torque Reference
Recommended torque values for B7 studs by size and lubrication condition.
Access Resource →
Material Grade Guide
A105 vs. F304 vs. F316 vs. F11. Which grade for which service.
Access Resource →
Corrosion Prevention
Coatings, galvanizing, and material selection for corrosive environments.
Access Resource →
Flange Dimension Tables
ASME B16.5 dimensional data. OD, bolt circle, bolt holes, thickness by class.
Access Resource →
Common Questions
Frequently Asked
What pressure range do piping flange standards actually cover end to end?+
Lightweight Class 125LW (86 psi) and AWWA C207 Class B through F (up to 300 psi) cover the waterworks side. ASME B16.5 covers Class 150 through Class 2500 for industrial process. API 6A and 6BX cover 2K through 20K psi for wellhead service. The full span is documented across the standards reference pages.
Are lightweight waterworks and high-pressure oilfield flanges from the same family?+
No. AWWA C207 lightweight and API 6A high-pressure are entirely separate standards with different dimensional, material, and pressure-rating rules. They share a vendor ecosystem because Texas Flange and similar industrial suppliers cover both, but the engineering for each is independent.
What size range do these standards cover?+
ASME B16.5 covers 1/2 inch through 24 inch NPS. ASME B16.47 picks up at 26 inch and runs through 60 inch in Series A and Series B. AWWA C207 covers 4 inch through 144 inch for steel water-service flanges. Larger custom diameters exist but are project-specific and quoted case by case at Texas Flange.
What are Buy American and ARRA flange requirements?+
Buy American and ARRA mean the flange must be melted and manufactured in the United States, with documentation that traces the material origin. PSL-3 and PSL-4 API material adds further NDE and impact testing requirements. Texas Flange supplies under these provisions when a project specifies them.
What is a mill test report (MTR) on a flange order?+
A mill test report ties each flange back to its original heat number with chemistry and mechanical properties. EN 10204 3.1 and 3.2 are the typical certification levels for industrial piping. Standard practice is for MTRs to ship with the material rather than be chased afterward.
How are lead times set on piping flange orders?+
Lead time depends on size, class, material, and any custom machining. Standard B16.5 carbon and stainless typically move faster than large-diameter A694 or API 6BX, which often involve mill production schedules. Project-specific timelines are confirmed at quote stage by the Texas Flange sales desk at (281) 484-8325.
Need Piping Flanges? Let's Talk.
Whether you need ten slip-ons for a maintenance job or ten thousand weld necks for a new build, the process starts with a conversation.