ASTM B466 C70600 seamless pipe and tube is produced for condensers and heat exchangers where seawater, brine or cooling water flows on one side and a hotter process stream on the other. The seamless route removes the longitudinal weld, so the wall is uniform around the circumference and the tube can be roller expanded into a tube sheet, bent into a U shape or finned without a weld zone interrupting the surface film.
What This Specification Covers
ASTM B466 (ASME SB466) is the specification for seamless copper-nickel pipe and tube, and C70600 is the 90/10 copper-nickel grade supplied under it. Tube for heat transfer duty is frequently ordered to ASTM B111 (ASME SB111) at the same time, because that specification defines the condenser tube dimensions and the expanded end condition that a tube sheet requires. Naval and defence programmes add their own designations such as CN102 and CuNi10Fe1Mn, which describe the same 90/10 alloy with iron and manganese additions.
Specification Range and Dimensions
| Parameter | Range |
|---|---|
| Outside diameter | 3 mm to 114.3 mm |
| Nominal bore | 1/4 in to 12 in |
| Wall thickness | Schedule 10 to schedule 160 |
| Length | 5 – 7 m, 9 – 13 m, single random, double random or cut to order |
| Manufacturing route | Seamless, cold drawn, hot finished or hot rolled |
| Pipe ends | Plain ends or bevelled ends |
| Delivery condition | As rolled, cold drawn, hot finish, stress relieved, annealed, hardened or tempered |
| Surface finish | Mechanical polish, satin finish or passivated |
| Packaging | Loose, bundle, wooden pallet, wooden box, plastic wrap or plastic end caps |
Composition and Mechanical Behaviour
| Element | Content |
|---|---|
| Copper (Cu) | Balance, about 90 % |
| Nickel (Ni) | 9.0 – 11.0 %, about 10 % |
| Iron (Fe) | 1.0 – 1.8 % |
| Manganese (Mn) | 1.0 % max |
| Zinc (Zn), lead (Pb), carbon (C), phosphorus (P), sulphur (S) | Trace residuals within specification limits |
Annealed tube shows tensile strength of about 275 MPa minimum with elongation in the region of 30 %, which gives ample ductility for expansion and bending.
Strength is moderate among copper-nickel grades, but it is more than adequate for exchanger shells and tube bundles once the wall is sized for pressure.
The alloy keeps its strength at moderately elevated temperatures and retains good cold and hot workability.
It is readily joined by common welding processes and by brazing, and weldability is good for both shop and site work.
Testing, Inspection and Documentation
Chemical analysis confirms the nickel, iron and manganese balance against the cast composition.
Dimensional checks cover outside diameter, wall thickness, ovality and straightness on every production length.
Flare and flattening tests demonstrate ductility, and hardness testing confirms the specified temper.
Eddy current examination detects wall defects in the finished tube, while hydrostatic testing verifies pressure integrity to the requested stress level.
Grain size checks are used where the tube will be expanded or bent, and intergranular corrosion testing is available for critical service.
Certificates are issued to EN 10204 3.1 or 3.2 as required, with independent inspection available when a project demands it.
Applications for Seamless Condenser and Exchanger Tube
Power station surface condensers and feedwater heater tube bundles.
Process industry shell and tube exchangers handling brackish or cooling water.
Chillers, refinery coolers and shipboard machinery cooling circuits.
Desalination distiller, evaporator and brine heater tube.
Finned tube and U-bend assemblies for compact heat transfer units.
Seawater piping headers, ferry stock and low pressure transfer lines between exchangers.
FAQ
Q: Why is seamless tube preferred over welded tube for exchangers?
A seamless wall has no longitudinal weld and no heat affected zone, so wall thickness is uniform around the circumference. That makes expansion into a tube sheet more predictable and removes a potential initiation site for corrosion in severe service.
Q: What wall thicknesses are available?
The pipe range covers outside diameters of 3 mm to 114.3 mm with wall thicknesses from schedule 10 to schedule 160, and custom sizes can be drawn for a specific exchanger design.
Q: How long can the tube be supplied?
Lengths of 5 m to 7 m and 9 m to 13 m are standard, in single random or double random form. Cut to length supply is available for tube sheets that call for an exact dimension.
Q: Which delivery condition should be specified?
Annealed tube is selected when the tube will be expanded, rolled or bent. Stress relieved and cold drawn conditions suit straight runs that need dimensional stability and higher strength.
Q: Can the tube be finned or bent into U shapes?
Yes. The alloy supports low fin forming and U-bend manufacture, and finned or U-bend tube is supplied for compact exchangers and for bundles that must fit inside a removable shell.
Q: Is C70600 suitable for steam service?
It is widely used in steam surface condensers and in low pressure steam duties. For superheated or high temperature steam lines, the design temperature and pressure must be checked against the allowable stress for the selected temper.
