Material selection
Copper Nickel Flanges
Copper-nickel flange enquiries must distinguish 90/10 and 70/30 alloy designations and identify which parts of the joint contact the process fluid.
Specify the alloy, not only a ratio
90/10 and 70/30 describe different copper-nickel alloy families. Provide the exact designation, applicable product specification and condition required by the project. A shorthand composition ratio alone is insufficient for material certification or substitution.
Solid versus composite connection
Some connections use a copper-nickel stub end with a separate backing flange. The backing material is not the process-wetted alloy. Specify each component, the lap dimensions, gasket seating and the fit between the stub end and backing flange.
Water service and commissioning
Water chemistry, flow, fouling and commissioning conditions need assessment for the selected alloy. Review mating materials and galvanic compatibility. A marine or seawater application label does not remove these checks or establish an unrestricted pressure-temperature rating.
Selection reference only. Offered scope, technical compliance and availability are confirmed against the complete project enquiry.
Material designations and distinctions
Reference designations for Copper Nickel Flanges. These are not an availability list or an equivalence table. A trade name, UNS number and ASTM product specification have different roles.
| Parameter / designation | Technical information | Selection requirement |
|---|---|---|
| 90/10 / UNS C70600 | Copper-nickel alloy designation | Confirm the product specification, grade/condition, design suitability and required material records. |
| 70/30 / UNS C71500 | Higher nickel content; not interchangeable without review | Confirm the product specification, grade/condition, design suitability and required material records. |
Compare related options
Compare Copper Nickel Flanges with the related forms or references below. A related product is not necessarily a permissible substitute.
| Related product / reference | Distinction | Check before selection |
|---|---|---|
| Monel Flanges | Monel nickel-copper flange enquiries should identify the alloy designation and condition. Alloy 400 and K-500 have different composition and strengthening requirements. | Exact designation, specification and condition |
| Lap Joint Assembly | In a lap-joint assembly, the stub end provides the gasket seating surface. The separate backing flange transfers bolt load and can rotate for alignment before tightening. | Backing flange and stub-end designations separately |
Inspection, documents and delivery
Define acceptance requirements for Copper Nickel Flanges in the purchase order. Required examinations and documents depend on the material, design and project specification.
| Review stage | Information to confirm | Order requirement |
|---|---|---|
| Material identity and traceability | Specification, grade, heat/lot identification and the required material certificate. | Agree documentation and marking before manufacture; visual appearance cannot verify alloy identity. |
| Dimensional verification | The selected flange form, bore, thickness, bolt pattern and mating geometry. | Identify inspection points, tolerances, units and drawing revision. |
| Surface and end condition | Gasket-contact surface, attachment end, edges and any coating exclusions. | State finish and visual acceptance criteria; agree protection of machined surfaces. |
| Supplementary examinations | Any specified PMI, NDE, hardness, impact, corrosion or other tests. | Define the method, sampling and acceptance criteria; tests are not automatically included. |
| Assembly compatibility | Adjoining components, weld or mechanical interface and project service conditions. | Design approval and correct assembly remain separate from a dimensional inspection report. |
| Packing and order release | Quantity, identification, surface protection, documents and delivery destination. | Agree preservation, packaging and release requirements with the order. |
Enquiry checklist
Details for Copper Nickel
Specify the complete joint and design conditions. This checklist is not a dimensional table or an engineering approval.
| Item | Requirement |
|---|---|
| Alloy | 90/10 or 70/30 with exact material designation |
| Components | Wetted component and backing flange materials separately |
| Service | Water chemistry, flow and commissioning requirements |
| Interface | Lap dimensions, gasket seating and bolting |
Continue the specification

