Energy Sector
Flanges and Fittings for Upstream, Midstream, and Downstream
From wellhead trees and BOP stacks to pipeline mainlines and refinery process units, oil and gas service demands the widest spread of pressure classes and material grades in the supply industry.
Industry Overview
How Oil & Gas Piping Actually Looks
Upstream operators run wellhead equipment, drilling spreads, and production manifolds at pressures that climb from API 2K through 20K. The metallurgy follows the well. Sweet service tolerates standard carbon, but sour wells covered by NACE MR0175 push specifications toward F22 chrome-moly and Inconel cladding to defeat sulfide stress cracking.
Midstream pipeline work is a different animal. Long runs of gathering, transmission, and distribution piping rely on weld neck flanges in A105 or A350 LF2 for low temperature service. MSS SP-44 large diameter flanges show up at compressor and pump stations where ASME B16.5 stops at 24 inch.
Downstream refining returns to high temperature and high pressure forgings with chrome-moly grades dominating hydroprocessing, FCC, and crude unit service. We supply across all three segments, often on the same order.
Typical Flange Selections
What We Supply for Oil & Gas
API 6A Wellhead Flanges
2K through 20K, ring joint
Christmas trees, BOP stacks, choke manifolds
Weld Neck, Class 600 to 2500
ASME B16.5, RTJ face
High pressure separators and production headers
Weld Neck, Class 150 to 900
ASME B16.5 / B16.47 Series A
Pipeline mainline, compressor stations
Blind Flanges
Class 150 through 2500
Vessel manways, pig launcher closures
Long Weld Neck
Custom bore, Class 600+
Nozzle replacement on production vessels
Ring Joint Gaskets
R and BX style, soft iron through Inconel
High pressure flange joints in sour service
Material Selection
Common Materials and Why
ASTM A105
Workhorse carbon steel for sweet service at moderate temperature. Lowest cost and broadest stocking depth.
ASTM A350 LF2
Low temperature carbon for cold weather pipeline service and impact tested applications down to minus 50 F.
ASTM A182 F22
2.25 Cr 1 Mo chrome-moly for high temperature hydroprocessing and sour service per NACE MR0175.
ASTM A182 F11
1.25 Cr 0.5 Mo for moderate elevated temperature service in refinery and gas processing.
Inconel 625 and 825
Severe sour wells with high H2S and chloride content where carbon steel cracking is a certainty.
Industry Challenges
What Procurement Has to Solve
- 01
Sour service certification with NACE MR0175 hardness limits and full PMI documentation.
- 02
Pressure class range from Class 150 process headers to API 20K wellhead in the same project scope.
- 03
Long lead time forgings in large diameter and exotic alloys that must be sourced against tight rig schedules.
- 04
Charpy impact testing for cold service pipelines crossing northern terrain.
Standards and Codes
Specifications We Quote To
Ready to Quote Oil & Gas
Send your line list with service conditions and NACE requirements and we will quote with full MTRs and PMI.
Texas Flange & Fitting Supply | PO Box 2889, Pearland TX 77588