Our ASTM A105 Carbon Steel Threaded Flanges solve low-pressure piping headaches where welding isn't practical. The rolled threads (ASME B1.20.1 compliant) bite deep into pipes without stripping – we've got test reports showing 30% higher pull-out strength than machined-thread competitors.
With 485-655 MPa tensile strength (per ASTM A105), they handle Class 150-300 systems up to 360°F (182°C) without sweating. The secret's in our controlled carbon range (0.25-0.29%): enough strength for steam lines, but still weldable when you need modifications. Compared to stainless, you'll save 40-65% per unit on non-corrosive applications like compressed air or hot oil circuits.
Every Carbon Steel Threaded Flange gets our signature treatment:
This flange is hot-forged from vacuum-degassed steel. With fewer impurities in the steel, there are fewer defects on the threads.
Before threading, stress relief treatment was done at 1200 degrees Fahrenheit (about 650 degrees Celsius) so that the threads are not easily deformed after processing.
CNC-cut threads with Class 2B fit (tighter than ASME's 3B requirement)
Zinc-plated per ASTM B633 Type II (48-hour salt spray tested)
We triple-check threads with go/no-go gauges AND 3D scanners – because leaky fittings cost you callbacks.
Running 4 dedicated lines with:
20000-piece monthly capacity (ready for refinery turnarounds)
150+ thread rolling dies (1/8" to 12" NPT all covered)
Real-time PMI checks (handheld XRF verifies chemistry on the spot)
Barcode-tracked MTCs with heat numbers (zero paperwork errors)
Need fast turnaround?
Our warehouse stocks 10,000+ ASME B16.5 threaded flanges – check live inventory anytime.
For wholesale partners
ASTM A105 (Carbon Steel)
ASTM A350 LF2 (Low-Temp Carbon Steel)
Q235B (Chinese Carbon Steel)
Mechanical Properties
485-655 MPa
485-655 MPa
375-500 MPa
Mechanical Properties
≥250 MPa
≥345 MPa
≥235 MPa
Operating Temp Range
-29°C ~ 427°C
-46°C ~ 427°C (excellent low-temp toughness)
-20°C ~ 300°C
Thread Compatibility
NPT, BSPT, BSPP
NPT, G-thread
Pressure Rating
Class 150 ~ 300 (standard)
Class 150 ~ 600
Class 150 ~ 300
Corrosion Resistance
Moderate (needs coating)
Moderate (needs coating)
Moderate (needs coating)
Installation Ease
High (no welding required)
Service Type
Thread Customization
Available in NPT (National Pipe Taper), BSPT (British Standard Pipe Taper), BSPP (parallel), and metric threads.
Pressure Class Options
Customizable to Class 150, 300, 600 (per ASME B16.5) or PN10, PN16, PN25 (per EN 1092-1).
Surface Treatments
Galvanizing, anti-rust painting, phosphate coating, or oiling (prevents corrosion during storage).
Material Certifications
Provides MTR (Material Test Report), EN 10204 3.1/3.2 certificates, and NACE MR0175 compliance for sour service.
After-Sales Support
12-month warranty, thread repair guidance, and replacement for manufacturing defects.
Industry/Scenario
Recommended Material
Suitable Media
Key Selection Tips
Plumbing & Domestic Water
Q235B, ASTM A105
Tap water, cold water
Prioritize cost; Class 150 sufficient for low pressure.
Oil & Gas (Low-Pressure Lines)
ASTM A105, A350 LF2
Natural gas, light oil (≤300 psi)
Choose LF2 for cold climates; ensure thread sealant compatibility.
Chemical Processing (Mild)
Neutral solvents, coolants
Avoid high temperatures (>400°C); use Teflon tape for sealing.
Fire Protection Systems
Water, fire-retardant fluids
Class 150 preferred for quick installation (no welding).
HVAC Piping
Q235B, ASTM A36
Refrigerants, hot water (≤100°C)
Opt for BSPP
No Welding Needed
Ideal for sites with strict fire safety rules or limited welding equipment.
Quick Installation/Removal
Easy to disassemble for maintenance or pipe modifications.
Cost-Effective
Lower labor costs compared to welded flanges (no welding labor/inspection).
Leak Resistance
Reliable with proper thread sealants (PTFE tape, anaerobic sealants).
Frequently Asked Questions
Q: What is your policy for product returns or replacements?
A: If products have quality issues caused by us, we'll arrange replacements or refunds within 30 days of receipt.
Q: Can you provide a certificate of origin (CO) for customs clearance?
A: Yes, we can provide CO, as well as other documents like commercial invoices and packing lists required for customs.
Q: How can we track the shipment after it's dispatched?
A: We'll provide a tracking number and logistics platform information once the shipment departs, so you can check the status in real time.
Q: Do you offer technical support for product installation or usage?
A: Yes, our technical team can provide installation guides, video tutorials, or even on-site support if needed.
