Butt-welding flange

A butt-welding flange (also known as a "butt weld flange") is a type of pipe flange designed to connect pipes by butt welding—a technique where the pipe end is beveled and welded directly to the flange's hub. This connection provides a strong, leak-resistant joint suitable for high-pressure, high-temperature, or critical service applications.​​​​​​​

What Are Butt-Welding Flanges?

Butt-welding flanges connect pipes by welding the flange neck to the pipe end, creating a smooth, robust joint. They’re ideal for:
✔ High-pressure systems (no weak points like bolt holes)
✔ Corrosive environments (seamless weld = no crevice corrosion)
✔ Critical applications (power plants, refineries, submarines)

Key Advantage: Unlike slip-on flanges, butt-welding flanges match the pipe thickness, ensuring equal stress distribution.

Material:

• Carbon Steel: ASTM A105,20#, Q235, 16Mn, ASTM A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2, ASTM A694 F42, F46, F48, F50, F52, F56, F60, F65, F70.
• Stainless Steel (Stainless Steel): ASTM A182 F304, 304L, F316, 316L, 1Cr18Ni9Ti, 0Cr18Ni9Ti, 321, 347, 347H, 18-8.
• Alloy Steel (Alloy Steel): ASTM A182 F1, F5a, F9, F11, F12, F22, F91, F12, F11, 16MnR, Cr5Mo, 12Cr1MoV, 15CrMo, 12Cr2Mo1, A335P22, St45.8/III.
• Low temperature steel: A522 A707 Grade L 1-L 2-L 3-L 4-L 5-L 6-L 7-L 8
• High Performance Steel: A694 F 42-F 46-F 48-F 50-F 52-F 56-F 60-F 65-F 70

How to Choose the Right Flange?

For Engineers & Manufacturers

🔹 Pressure Rating: Match to system requirements (150#, 300#, 600#, etc.).
🔹 Face Type: RF (Raised Face), FF (Flat Face), RTJ (Ring-Type Joint).
🔹 Coating/Galvanization: Needed for outdoor or corrosive environments?

For Procurement Specialists

🔸 Supplier Audit: Check for ISO 9001, API 6A, PED certifications.
🔸 Lead Time: Standard flanges (2-4 weeks), custom (6-8 weeks).
🔸 Cost-Saving Tip: Bulk orders (50+ units) often get 10-15% discounts.

For DIY & Small Businesses

🔸 Avoid Overkill: Don’t buy 600# flanges for a low-pressure water line.
🔸 Welding Prep: Ensure your welder knows AWS D1.1 procedures.

Common Mistakes to Avoid

Mismatching materials (e.g., carbon steel flange on stainless pipe = galvanic corrosion).
Ignoring face finish (RF flanges need gaskets, FF flanges don’t).
Skipping NDT (Radiography or ultrasonic testing for critical welds).

Why We're Your Best Flange Source

✔ Direct Mill Relationships: Cutting out middleman markups
✔ Quality Assurance: Every flange laser-marked for traceability
✔ Technical Support: Our engineers answer your calls
✔ Emergency Services: 24/7 shipment for critical outages

Special Offer: Mention this guide for 5% off your first order of $5,000+.

📞 Need a quote? Contact us today—we’ll help you find the perfect butt-welding flange for your project!

Tel: +86-29-89506568
WA/Mob: +86-17778976690
Email: linhui@lhtitanium.com