Start with the Service, Not the Metal Name
| Input | Why it matters | What the RFQ should state |
|---|---|---|
| Water chemistry | pH, chlorides, copper ions and treatment chemicals affect corrosion risk | Available water analysis and treatment range |
| Potable vs process water | Health/contact approvals and design codes differ | Intended service and governing jurisdiction |
| Pressure and temperature | Control wall design, joints and allowable material properties | Design/operating pressure and temperature |
| Joining system | Threads, welds, mechanical couplings and seals create different risks | Approved joint type and components |
| Dissimilar metals | Copper, brass and steel can create galvanic couples | All connected metals and isolation method |
Corrosion Risks to Evaluate
Pitting and stagnant zones
Chlorides, deposits and stagnant water can locally break down the protective oxide. Drainage, cleaning, flow regime and water treatment should be considered.
Galvanic corrosion
Direct electrical contact with copper alloys or other more noble metals can concentrate attack on aluminum when water provides an electrolyte. Approved isolation components and joint design are required.
Erosion, crevices and deposits
High local velocity, crevices at seals, trapped debris and poorly drained branches may create conditions different from the main pipe. System layout and commissioning cleanliness matter.
Potable-Water Claims Require Evidence
Do not treat “non-toxic metal” as proof that a complete pipe system is approved for drinking water. Compliance may apply to a specific alloy, lining, fitting, seal, joining process and installed system under a named standard or local regulation. Request the exact approval and scope rather than a general statement.
When Aluminum May Be Considered
Engineered aluminum piping can be considered in applications where the system supplier and designer have validated the alloy, joints, water chemistry, pressure/temperature and applicable code. It is also used in non-potable or specialized systems, but each case requires the same material-compatibility review.
RFQ Checklist
- Fluid and potable/process classification
- Water chemistry and treatment chemicals
- Design and operating pressure/temperature
- Alloy, temper and governing product specification
- OD, wall, length and tolerances
- Joining system, fittings, seals and dissimilar metals
- Required approvals, testing and documentation
Send the water chemistry, design conditions and applicable code so the material request can be evaluated without assuming universal suitability.
Post time: Jun-25-2025