ASTM B61 C92200 Fittings – Steam & Valve Bronze (Navy M)
What is ASTM B61? ASTM B61 is the standard specification for steam or valve bronze castings. It covers one alloy – UNS C92200, also known as Navy M or steam bronze: about 88% copper, 6% tin, 1.5% lead and 4.5% zinc. Its higher tin and lower lead give more strength than ASTM B62 C83600, so B61 fittings and valves are used for steam service up to about 550 °F (288 °C).
We supply ASTM B61 C92200 fittings – threaded, solder and flanged – to ASME B16.15, B16.18 and B16.24 dimensions, with EN 10204 3.1 certificates. See our copper alloy fittings range.
C92200 Chemical Composition (ASTM B61)
| Element | Composition (wt %) |
| Copper (Cu) | 86.0 – 90.0 |
| Tin (Sn) | 5.5 – 6.5 |
| Lead (Pb) | 1.0 – 2.0 |
| Zinc (Zn) | 3.0 – 5.0 |
| Iron (Fe) | 0.25 max |
| Antimony (Sb) | 0.25 max |
| Nickel (Ni, incl. Co) | 1.0 max |
| Sulphur (S) | 0.05 max |
| Phosphorus (P) | 0.05 max |
| Aluminium (Al) | 0.005 max |
| Silicon (Si) | 0.005 max |
Compared with B62 C83600 (85-5-5-5), C92200 has more copper and tin and less lead and zinc – which raises strength and pressure-tightness at steam temperatures.
ASTM B61 vs ASTM B62
| Property | ASTM B61 – C92200 | ASTM B62 – C83600 |
| Common name | Steam / valve bronze, Navy M | Composition bronze, 85-5-5-5 |
| Copper / tin | 86–90% Cu, 5.5–6.5% Sn | 84–86% Cu, 4–6% Sn |
| Lead / zinc | 1–2% Pb, 3–5% Zn | 4–6% Pb, 4–6% Zn |
| Tensile strength (min) | 234 MPa (34 ksi) | 205 MPa (30 ksi) |
| Yield strength (min) | 110 MPa (16 ksi) | 95 MPa (14 ksi) |
| Elongation (min) | 22% | 20% |
| Steam service | Up to ≈ 550 °F (288 °C) | Lower – ≈ 406 °F (208 °C) for steam |
| Typical use | Steam valves & fittings, higher-pressure service | Water, oil and low-pressure service |
See also: ASTM B62 C83600 fittings. Exact pressure–temperature ratings depend on the fitting standard and class.
ASTM B61 Fitting Types, Sizes & Standards
| Item | Details |
| Fitting types | Elbows, tees, crosses, couplings, unions, reducers, caps, plugs, bushings, flanges |
| Threaded fittings | ASME B16.15 (Class 125 / 250) |
| Solder-joint fittings | ASME B16.18 |
| Flanges | ASME B16.24 (Class 150 / 300) |
| Sizes | 1/8″ to 4″ typical; larger on request |
| End connections | Threaded (NPT / BSP), solder, flanged |
| Production | Sand or centrifugal cast, then machined |
Mechanical Properties of ASTM B61 C92200
| Property | Value |
| Tensile strength (B61 min) | 234 MPa (34 ksi) |
| Yield strength (B61 min) | 110 MPa (16 ksi) |
| Elongation in 50 mm (B61 min) | 22% |
| Hardness (typical) | ≈ 65 HB |
ASTM B61 C92200 Specifications
| Item | Details |
| Material standard | ASTM B61 – steam or valve bronze castings |
| Alloy | UNS C92200 (Navy M, steam bronze) |
| Related standards | ASTM B505 (continuous castings), B584, SAE J462, MIL-B-16541 |
| Dimensional standards | ASME B16.15, B16.18, B16.24 |
| Product forms | Fittings, flanges, valve bodies and components |
| Test certificate | EN 10204 3.1; third-party inspection on request |
C92200 Equivalent Grades
| Standard | Nearest equivalent |
| UNS | C92200 |
| Common names | Navy M bronze, steam bronze, valve bronze |
| EN 1982 | CuSn6Zn4Pb2-C (CC498K) |
| JIS H5120 | CAC407 (close) |
| US military | MIL-B-16541 |
Equivalents are close but not identical – check chemistry and test requirements before substituting.
Physical Properties of C92200
| Property | Value (approx.) |
| Density | 8.64 g/cm³ (0.312 lb/in³) |
| Melting range | 826 – 988 °C (1,518 – 1,810 °F) |
| Thermal conductivity | ≈ 70 W/m·K |
| Electrical conductivity | ≈ 14% IACS |
| Coefficient of thermal expansion | ≈ 17.3 µm/m·°C (20–300 °C) |
| Modulus of elasticity | ≈ 96 GPa (14 × 10⁶ psi) |
Applications of ASTM B61 C92200 Fittings
| Industry | Typical uses |
| Steam systems | Steam valves, fittings and flanges up to ≈ 288 °C |
| Power & process plants | Medium-pressure steam, condensate and hot-water lines |
| Marine | Valves, pump parts and fittings (Navy M bronze) |
| Pumps & hydraulics | Impellers, valve components, medium-pressure hydraulic parts |
| Cryogenic | Valve bodies and components for low-temperature service |
Why Buy ASTM B61 C92200 Fittings from ASC LLP?
- Certified material: ASTM B61 castings with EN 10204 3.1 certificates and heat traceability.
- Full range: threaded, solder and flanged fittings to ASME B16.15, B16.18 and B16.24.
- Matching products: ASTM B62 C83600 fittings, copper alloy flanges and other copper alloys.
- Inspection: PMI, pressure testing and third-party inspection on request.
- Export packing and regular shipments worldwide.
Send your size, type, class and quantity to sales@amardeepsteel.com or call 022-67439130.
Frequently Asked Questions – ASTM B61 C92200
What is ASTM B61?
ASTM B61 is the standard specification for steam or valve bronze castings. It covers copper alloy UNS C92200 (Navy M bronze), used for valves, flanges and fittings in steam service up to about 550 °F (288 °C).
What is the chemical composition of C92200?
C92200 contains 86.0–90.0% copper, 5.5–6.5% tin, 1.0–2.0% lead and 3.0–5.0% zinc, with limits on iron (0.25 max), antimony (0.25 max), nickel (1.0 max), sulphur and phosphorus (0.05 max each).
What is the difference between ASTM B61 and ASTM B62?
B61 (C92200) has more copper and tin and less lead and zinc than B62 (C83600), giving higher strength – 234 MPa vs 205 MPa minimum tensile – and a higher steam service temperature, about 550 °F compared with about 406 °F for B62.
What are the mechanical properties of ASTM B61?
ASTM B61 C92200 requires a minimum tensile strength of 234 MPa (34 ksi), minimum yield strength of 110 MPa (16 ksi) and minimum elongation of 22%.
Is C92200 the same as Navy M bronze?
Yes. UNS C92200 is commonly called Navy M bronze, steam bronze or valve bronze, and is also covered by MIL-B-16541.
Global Reach
ASC LLP supplies bronze and copper-alloy fittings, valves and flanges to power, process, marine and utility customers worldwide, with prompt delivery and full documentation. Buyers in the USA, Europe, the Middle East and Asia rely on our ASTM B61 C92200 fittings for certified material and traceability.
Countries We Export To
UNITED STATES, EUROPE, UK, UAE, SAUDI ARABIA, OMAN, KUWAIT, JORDAN, QATAR, INDONESIA, MALAYSIA, BRAZIL, SPAIN, ITALY, FRANCE, GERMANY, BAHRAIN, SRI LANKA, AZERBAIJAN, AUSTRALIA, AUSTRIA, PHILIPPINES, TURKEY, RUSSIA, IRAN, IRAQ, CANADA, KOREA, JAPAN, YEMEN, FINLAND, ZIMBABWE, HUNGARY, PORTUGAL, VIETNAM, MOROCCO, THAILAND, SOUTH AFRICA, MEXICO, SINGAPORE, GREECE, KUWAIT, POLAND, NEW ZEALAND, SWEDEN, SWITZERLAND, BELGIUM, BHUTAN, BANGLADESH, TAIWAN, ROMANIA, CAMBODIA, KAZAKHSTAN, AFGHANISTAN.
