ASTM forged fittings are critical components in petrochemical, power, and offshore piping. They follow ASTM material standards and ASME B16.11 dimensional standards. High strength. Excellent sealing. Reliable under severe service.
This guide covers ASTM A105, A182, A350 LF2, and A694 materials. Includes socket weld and threaded fitting types. Plus pressure classes, wall thickness matching, and selection rules. For engineers and procurement teams.
Why ASTM Forged Fittings Matter in High-Pressure Piping
Piping safety drives project success. ASTM forged fittings deliver strength and sealing reliability. They outperform cast or fabricated alternatives. Engineers and buyers focus on them for good reason.
This ASTM forged fittings selection guide covers:
- Material standards – ASTM A105, A182, A350 LF2, A694
- Product types – socket weld and threaded
- Key technical parameters
- Selection criteria for your project
ASTM vs ASME Standards – What Each Covers
ASTM defines chemical composition and mechanical properties.
ASME B16.11 defines dimensions, tolerances, and pressure-temperature ratings.
MSS SP series covers special fittings like branch outlets.
|
Standard Type |
What It Covers |
|
ASTM Material Standards |
Chemical composition, mechanical properties, heat treatment |
|
ASME B16.11 |
Dimensions, pressure classes, marking, tolerances |
|
MSS SP-79 / 83 / 85 / 97 |
Branch outlets, special fittings, dimensional requirements |
Both are required. One without the other is incomplete.
ASTM Forged Fitting Materials – Selection Chart
Different materials suit different services. Choose by temperature, pressure, and corrosion risk.
|
Material |
ASTM Grade | Key Features |
Typical Service |
|
Carbon Steel |
ASTM A105 | Good overall performance, high-temp capable |
General industry, high-temp piping |
|
Low-Temp Carbon Steel |
ASTM A350 LF2 | Excellent low-temp impact toughness, -46°C min |
LNG, chemical refrigeration |
|
Pipeline Steel |
ASTM A694 F42–F65 | High strength, HIC resistant |
Oil & gas high-pressure lines |
|
Alloy Steel |
ASTM A182 F11 / F12 / F5 / F9 / F91 / F92 | Heat resistant, creep resistant |
High-temp high-pressure steam |
|
Stainless Steel |
ASTM A182 F304/304L/304H, 316/316L, 310S, 317, 347, 904L |
Excellent corrosion resistance |
Chemical, food, pharmaceutical |
|
Duplex Stainless |
ASTM A182 F51, F53, F44 | High strength + stress corrosion resistance |
Offshore, oilfield piping |
- Carbon steel – low cost, good machinability. For ambient, low-to-medium pressure.
- Stainless steel – corrosion resistance. For chemical, food, pharma.
- Alloy steel – high strength, heat resistance. For high-temp, high-pressure.
Carbon Steel Fittings – A105, A350 LF2, A694
|
Standard |
Material | Key Properties |
Typical Application |
|
ASTM A105 |
Carbon Steel | Good overall, high-temp high-pressure capable |
General industrial, high-temp piping |
|
ASTM A350 LF2 |
Low-Temp Carbon Steel | Good low-temp impact toughness, -46°C min |
LNG, chemical refrigeration |
|
ASTM A694 |
Carbon / Alloy Steel | High strength, HIC resistant |
Oil & gas high-pressure piping |
ASTM A105 Carbon Steel Forged Fittings
ASTM A105 covers carbon steel forgings. Used for flanges, valves, and fittings in high-temp, high-pressure service.
Chemical Composition
| CHEMICAL | LIMITS | C | Mn | P | S | Si | Cu | Ni | Cr | Mo | V |
| ASTM A105 | MIN | 0.60 | 0.10 | ||||||||
| MAX | 0.35 | 1.05 | 0.035 | 0.040 | 0.35 | 0.40 | 0.40 | 0.30 | 0.12 | 0.08 |
Mechanical Properties
|
Material |
T.S (MPa) | Y.S (MPa) | EL % | R/A % | Hardness |
|
ASTM A105 |
485 min | 250 min | 22 min | 30 min |
197 max |
ASTM A350 LF2 Low-Temp Carbon Steel Fittings
Designed for low-temperature service. Suitable for -46°C and above. Good impact toughness. Used in LNG, chemical, and refrigeration.
Chemical Composition
| CHEMICAL | LIMITS | C | Mn | P | S | Si | Cu | Ni | Cr | Mo | V | Nb |
| ASTM A350 LF2 | MIN | 0.60 | 0.15 | |||||||||
| MAX | 0.30 | 1.35 | 0.035 | 0.040 | 0.35 | 0.40 | 0.40 | 0.30 | 0.12 | 0.08 | 0.02 |
Mechanical Properties
|
Material |
T.S (MPa) | Y.S (MPa) | EL % | R/A % |
Hardness |
|
ASTM A350 LF2 |
485–655 | 250 min | 22 min | 30 min |
197 max |
ASTM A694 High-Strength Pipeline Fittings
For high-pressure oil and gas piping. High strength. HIC resistant. Grades F42 through F65.
Chemical Composition (F42)
| CHEMICAL | LIMITS | C | Mn | P | S | Si |
| ASTM A694 F42 | MIN | 0.15 | ||||
| MAX | 0.30 | 1.60 | 0.025 | 0.025 | 0.35 |
Mechanical Properties
|
Material |
T.S (MPa) | Y.S (MPa) |
EL % |
|
ASTM A694 F42 |
415 min | 290 min |
20 min |
Alloy & Stainless Steel Fittings – ASTM A182
|
Standard |
Material | Key Properties |
Typical Application |
|
ASTM A182 F11/F12 |
Alloy Steel | Heat resistant, creep resistant |
High-temp high-pressure steam |
|
ASTM A182 F304/316 |
Stainless Steel | Excellent corrosion resistance |
Chemical, food, pharmaceutical |
|
ASTM A182 F51 |
Duplex Stainless | High strength, stress corrosion resistant |
Offshore, oilfield piping |
ASTM A182 covers stainless and alloy steel forgings for high-temp and corrosive service. Choose grade by media, temperature, and pressure. Check corrosion resistance, heat treatment, and certification.
ASTM A182 F12 Alloy Steel Fittings
Chemical Composition
| CHEMICAL | LIMITS | C | Mn | P | S | Si | Ni | Cr | Mo |
| ASTM A182 F12 CL1 | MIN | 0.05 | 0.30 | 0.80 | 0.44 | ||||
| MAX | 0.15 | 0.60 | 0.45 | 0.45 | 0.50 | 1.25 | 0.65 | ||
| ASTM A182 F12 CL2 | MIN | 0.10 | 0.30 | 0.10 | 0.80 | 0.44 | |||
| MAX | 0.20 | 0.80 | 0.40 | 0.40 | 0.60 | 1.25 | 0.65 |
Mechanical Properties
| MATERIAL | ASTM A182 F12 CL1 | ASTM A182 F12 CL2 |
| T.S (MPA) | 415 min | 485 min |
| Y.S (MPA) | 220 min | 475 min |
| EL % | 20 min | 20 min |
| R/A % | 45 min | 30 min |
| HARDNESS | 121-174 | 143-207 |
ASTM A182 F316 Stainless Steel Fittings
Chemical Composition
| CHEMICAL | LIMITS | C | Mn | P | S | Si | Ni | Cr | Mo | N |
| ASTM A182 F316 | MIN | 10.00 | 16.00 | 2.00 | ||||||
| MAX | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 14.00 | 18.00 | 3.00 | 0.01 |
Mechanical Properties
|
Material |
T.S (MPa) | Y.S (MPa) | EL % |
R/A % |
|
ASTM A182 F316 |
515 min | 205 min | 30 min |
50 min |
ASTM A182 F51 Duplex Stainless Steel Fittings
Chemical Composition
| CHEMICAL | LIMITS | C | Mn | P | S | Si | Ni | Cr | Mo | N |
| ASTM A182 F51 | MIN | 4.50 | 21.00 | 2.50 | 0.08 | |||||
| MAX | 0.03 | 2.00 | 0.030 | 0.020 | 1.00 | 6.50 | 23.00 | 3.50 | 0.20 |
Mechanical Properties
| Material | T.S (MPa) | Y.S (MPa) | EL % | R/A % |
| ASTM A182 F51 | 620 min | 450 min | 25 min | 45 min |
Types of ASTM Forged Fittings – Socket Weld & Threaded
ASTM forged fittings come in two main connection types:
Socket Weld (SW) – pipe inserts into socket, then welded
Threaded (THRD) – threaded connection, NPT or BSP
Socket Weld Fittings – ASME B16.11
Socket weld fittings offer high connection strength and excellent sealing. For high-pressure, high-temp, and leak-critical service.
|
Parameter |
Specification |
|
Size Range |
1/4″ to 4″ (DN6 to DN100) |
|
Pressure Classes |
Class 3000, 6000, 9000 LBS |
|
Manufacturing Standards |
ASME B16.11, BS3799, MSS SP-79 / 83 / 85 / 97 |
|
Product Types |
SW elbows, tees, crosses, caps, couplings, unions, branch outlets |
Socket Weld Fitting Pressure Class vs Pipe Wall Thickness
|
Connection Type |
Pressure Class |
Matching Pipe Schedule |
|
Socket Weld |
3000 |
Sch80, XS |
|
Socket Weld |
6000 |
Sch160 |
|
Socket Weld |
9000 |
XXS |
Threaded Fittings – ASME B16.11
Threaded fittings allow easy installation and removal. Ideal for low-pressure, small-bore piping. Easy maintenance.
|
Parameter |
Specification |
|
Size Range |
1/8″ to 4″ NPS |
|
Pressure Classes |
Class 2000, 3000, 6000 |
|
Manufacturing Standards |
ASME B16.11, BS3799, MSS SP-79 / 83 / 85 / 97 |
|
Product Types |
Threaded elbows, tees, crosses, couplings, unions, branch outlets, plugs, bushings, nipples, hex nipples |
Threaded Fitting Pressure Class vs Pipe Wall Thickness
|
Connection Type |
Pressure Class |
Matching Pipe Schedule |
|
Threaded (THRD) |
2000 |
Sch80 / XS |
|
Threaded (THRD) |
3000 |
Sch160 |
|
Threaded (THRD) |
6000 |
XXS |
Summary: Socket weld fittings – high strength, excellent sealing. For leak-critical systems. Threaded fittings – easy assembly, easy maintenance. Together they build flexible, reliable piping systems.
ASTM Forged Fitting Selection – Key Factors
- Connection Type: Socket Weld (SW) or Threaded (THRD)
- Pressure Class: 2000, 3000, 6000, 9000
- Manufacturing Standard: ASME B16.11, MSS SP-79/83/85/97
- Branch Outlet Standard: MSS SP-97 for weld-in branch outlets – stricter structure and dimensions
ASTM Forged Fittings FAQ
Q1: What is the relationship between ASME and ASTM standards?
ASTM defines material properties. ASME (e.g., B16.11) defines dimensions, pressure classes, and design tolerances.
Q2: What pressure classes are available for forged fittings?
Threaded: Class 2000, 3000, 6000. Socket Weld: Class 3000, 6000, 9000.
Q3: What connection types are available?
Socket Weld (SW) and Threaded (NPT/BSP).
Q4: Why do ASTM forged fittings have excellent mechanical properties?
Forging creates a dense internal structure. No inclusions. High strength, hardness, and toughness. Withstands high pressure and temperature. Long service life. Lower maintenance.
Q5: What are the dimensional advantages?
Forging enables strict dimensional control. Consistent fit. Reduced installation errors. Higher efficiency.
Q6: Why is sealing performance excellent?
Tight grain structure. No capillary cracks or voids. Excellent sealing. Prevents media leakage in chemical and energy industries.
Q7: What to check when buying ASTM A182 F51 duplex fittings?
Focus on corrosion resistance and impact toughness. Require full heat treatment reports and mechanical test reports. Verify pitting and stress corrosion cracking resistance.
Q8: How is corrosion resistance?
Stainless and alloy steel grades offer strong corrosion resistance in harsh environments.
Q9: How about weldability and formability?
Good weldability. Easy to weld with flanges, valves, and other components. Good formability. Heat treatment can alter shape and properties.
Q10: What industries use ASTM forged fittings?
Petrochemical, power, food & beverage, pharmaceutical, construction & municipal, offshore & shipbuilding. For high-temp, high-pressure, corrosion-resistant, and contamination-free service.
ASTM Forged Fittings – Procurement & Customization
Every project is unique. We supply full standard ranges per ASTM and ASME. We also offer material customization (special alloys) and non-standard dimensions.
Get support now:
Fast quote for ASTM forged fittings
Complete ASTM forged fitting Data Sheet
Material certificates and test reports
Contact:
E-mail:info@zzsteels.com