UNS C83600 Gunmetal Flanges Manufacturer & Exporter
UNS C83600 — commonly called gunmetal, composition bronze or red bronze — is the traditional general-purpose cast alloy for valves, pump parts and pipe fittings, and the material behind our gunmetal flanges.
UNS C83600 — Leaded red brass / composition bronze (Cu-Sn-Pb-Zn)
C83600 is the alloy designated “85-5-5-5” for its nominal 85% copper with 5% each of tin, lead and zinc. It is covered by ASTM B62 as a composition bronze or ounce metal casting alloy. In everyday trade language it is called gunmetal, composition bronze or red bronze, and these names are often used interchangeably with the C83600 designation.
Gunmetal flanges in UNS C83600 are widely used on pipework, pumps and valves for water, steam at moderate conditions, oil and many general industrial fluids. Our gunmetal pipe flanges, gunmetal valve flanges and gunmetal fitting flanges are made to customer drawings or the standard named in your enquiry, and exported to international customers.
Terminology note: the word “gunmetal” is also used for other copper-tin-zinc casting alloys in national standards (for example in British practice). If your specification names a different gunmetal grade, send us the exact standard and grade so that the correct material is quoted.
Designation
| UNS designation | C83600 |
|---|---|
| Alloy classification | Leaded red brass / composition bronze (Cu-Sn-Pb-Zn) |
| Also known as | gunmetal, composition bronze, red bronze, ounce metal, 85-5-5-5 |
| Applicable specifications | ASTM B62 (composition bronze or ounce metal castings); ASTM B584 (sand castings) |
C83600 chemical composition
Composition limits in weight %, as commonly published for this UNS designation in the stated ASTM specification. Chemistry limits are reproduced for reference; the current edition of the applicable specification governs.
| Element | Weight % |
|---|---|
| Copper (Cu) | 84.0 – 86.0 |
| Tin (Sn) | 4.0 – 6.0 |
| Lead (Pb) | 4.0 – 6.0 |
| Zinc (Zn) | 4.0 – 6.0 |
| Nickel incl. cobalt (Ni) | 1.0 max |
| Iron (Fe) | 0.30 max |
| Antimony (Sb) | 0.25 max |
| Sulphur (S) | 0.08 max |
| Phosphorus (P) | 0.05 max |
C83600 mechanical properties
Source: ASTM B62, sand castings.
| Property | Requirement |
|---|---|
| Tensile strength, min | 30 ksi (205 MPa) |
| Yield strength (0.5% ext. under load), min | 14 ksi (95 MPa) |
| Elongation in 2 in. / 50 mm, min | 20 % |
Minimum values shown are the tension-test requirements of the stated specification for separately cast test bars. Properties measured on an actual flange casting can differ. Values vary according to applicable specification, material condition and customer requirements. Confirm against the current edition of the specification and your purchase order before ordering.
Physical and processing data
| Property | Typical / reference value |
|---|---|
| Approximate density | about 8.8 g/cm³ |
| Approximate machinability rating | about 90 (free-cutting brass = 100) |
| Magnetic behaviour | Non-magnetic |
Physical values are typical reference values for the alloy family, not guaranteed values. Values vary according to applicable specification, material condition and customer requirements.
Manufacturing forms for C83600 flanges
- Sand castings machined to flange dimensions
- Pipe, valve and pump flanges to standard or drawing
- Threaded, blind, plate and special gunmetal flanges
Machining characteristics
C83600 is among the easiest cast copper alloys to machine. Faces, bores, threads and drilled holes are produced with high surface quality, which is why this gunmetal has been a long-standing choice for fittings and valve-related flanges.
Corrosion characteristics
Gunmetal has good resistance to corrosion in fresh water, many neutral and mildly alkaline waters, and moderately saline conditions; it is also commonly used with steam, oil and general-purpose industrial fluids at moderate conditions. It is not the preferred material for high-velocity seawater or strongly oxidising media.
C83600 contains lead. For drinking-water installations, check the lead-content requirements of the destination market before selecting this grade; it must not be assumed suitable for potable service.
Why specify C83600 for flanges
- Excellent castability and good pressure tightness
- Very good machinability for accurate threads and faces
- Long-established, widely recognised grade for valves, pumps and fittings
- Good general corrosion resistance in water and many industrial fluids
Gunmetal flange products
The most common requests for UNS C83600 are threaded gunmetal flanges for pipe connections that avoid welding, blind gunmetal flanges for isolation and testing, and plate gunmetal flanges for brazed or fabricated assemblies. Custom gunmetal flanges are made to your drawing.
Where gunmetal is used
- Valves: body and bonnet flanges, valve-end connections
- Pumps: suction and discharge flanges on water and oil pumps
- Pipework: gunmetal pipe flanges on non-potable water, cooling and general service lines
- Fittings: flanged gunmetal fittings and adaptors
Selection of a flange material remains the responsibility of the system designer; always confirm the grade against the medium, temperature, pressure and applicable regulations.
C83600 flanges we manufacture
- Threaded / Screwed FlangesThreaded flanges connect to pipe through an internal thread, avoiding welding at the joint.
- Slip-On FlangesSlip-on flanges are machined from bronze and copper-alloy grades so that the pipe slides into the bore and is secured by fillet welding or brazing, depending on material and procedure..
- Blind FlangesBlind flanges are solid discs used to close the end of a pipe, valve or pressure vessel nozzle.
- Plate FlangesPlate flanges are flat rings with a bore and a bolt-hole pattern.
- Custom / Special FlangesSend your drawing, sample or specification.
- All flange typesSlip-on, threaded, blind, socket-weld, lap joint, plate, reducing, loose and custom.
Inspection and testing
Dimensional and visual inspection are applied to all orders, with material identification and chemistry or mechanical testing as specified in the order. Certificates such as an MTC are issued as agreed at order stage. See Quality.
C83600 flanges: common questions
What is UNS C83600?
UNS C83600 is a Leaded red brass / composition bronze (Cu-Sn-Pb-Zn), also known as gunmetal, composition bronze, red bronze, ounce metal, 85-5-5-5. It is covered by ASTM B62 (composition bronze or ounce metal castings); ASTM B584 (sand castings). UNS C83600 — commonly called gunmetal, composition bronze or red bronze — is the traditional general-purpose cast alloy for valves, pump parts and pipe fittings, and the material behind our gunmetal flanges.
Does Sunflex Metalloy manufacture and export C83600 flanges?
Yes. Sunflex Metalloy Pvt. Ltd. manufactures UNS C83600 flanges at its units in Gujarat, India and exports them, made to the customer drawing or the applicable dimensional standard.
Which flange types are available in C83600?
C83600 flanges are commonly requested as threaded / screwed flanges, slip-on flanges, blind flanges, plate flanges, custom / special flanges. Other types, including socket-weld, lap joint, reducing and loose flanges, can be discussed against your drawing. Available as per applicable material and dimensional standard.
What should I send with an RFQ for C83600 flanges?
Send the drawing or standard, nominal size or dimensions, quantity, facing and finish, required certificates (for example MTC) and the delivery country, using the enquiry form or sales@sunflexmetalloy.com. Values vary according to applicable specification, material condition and customer requirements.
Have a Bronze Flange Requirement?
Send us your drawing, specification, material grade, size and quantity.