Industry procurement solution · Reviewed 10 August 2026

Metals for Water Treatment and Desalination

Water-treatment metal selection begins with feed and concentrate chemistry, chlorides, oxidants, pressure, temperature, velocity, stagnation, crevices, cleaning and dissimilar-metal interfaces—not a generic stainless grade list.

01 Service environment02 System requirements03 Codes & documents04 Inspection & delivery

Answer first

There is no single metal specification for an entire project

Divide the project into systems, document each service environment and governing code, then select compatible materials, product standards, fabrication routes, protection systems and inspection plans.

01Service environment

Raw water, brackish water, seawater, concentrate and chemical dosing with different corrosion severity

02Service environment

High-pressure membrane trains, variable velocity, shutdown stagnation and oxygen or disinfectant transients

03Service environment

Wet external areas, insulation, splash, leaks and mixed-metal supports

System map

Material and product selection by project system

SystemSelection drivers and alternativesReviewed starting points
Intake and pretreatment
  • Map suspended solids, biofouling, erosion, chlorination and low-flow zones before selecting pipe and screens.
  • Material, coating and cathodic-protection interfaces require one corrosion-control basis.
Carbon steel pipeStainless sheet
High-pressure membrane piping
  • Specify design pressure, chloride and oxidant limits, grade, product standard, weld procedure, PMI and pressure testing.
  • Standard 304L or 316L can corrode rapidly in severe seawater conditions; alloy selection requires project chemistry.
2507Stainless pipe
Chemical dosing and cleaning
  • Evaluate concentrated chemicals, dilution points, temperature, splash and cleaning sequence separately.
  • Small valves, fittings and instruments must match the piping material class and corrosion study.
316LStainless pipe
Skids, tanks and external structures
  • Separate internal fluid compatibility from external splash, condensation, coating and drainage requirements.
  • Detail crevices, weld finish, access and mixed-metal supports for inspection and maintenance.
Stainless sheetGalvanized coil

Project control

Standards, certification and documents

  • Design basis with complete feed, product, concentrate and cleaning chemistry
  • Process line list, pressure class, corrosion study and materials selection report
  • Welding, PMI, passivation, NDE, pressure-test and coating procedures
  • Material certificates, weld map, inspection plan and turnover dossier

Fabrication and logistics

Package interfaces to control

  • Fabrication drawings, welding, heat treatment, coating and repair procedures
  • Inspection hold points, testing methods, acceptance criteria and document approval
  • Identification through cutting and assembly, preservation, packing and consolidated shipping
  • Destination rules, site storage, installation interfaces and delivery sequence

Risk register

Common procurement risks

01

Assuming 316L is universally seawater resistant

02

Ignoring stagnation, crevices, oxidant spikes or concentrate chemistry

03

Mixing grades during fabrication without positive material identification

04

Specifying pipe without compatible fittings, weld consumables, valves and test requirements

Comparable offers

Structured RFQ checklist

01RFQ input

Project location, service environment, design life and governing codes

02RFQ input

System or component, selected material and governing product specification

03RFQ input

Dimensions, tolerances, quantity and required delivery sequence

04RFQ input

Condition, finish, metallic coating, paint system or corrosion allowance

05RFQ input

Fabrication, forming, welding, heat treatment and qualification requirements

06RFQ input

Inspection and test plan, acceptance criteria, certificates and hold points

07RFQ input

Marking, traceability, packing, preservation and destination

08RFQ input

Required delivery date, shipment terms and approved-vendor constraints

Evidence

Sources and review

Project engineering documents and current governing standards supersede this general selection map.

Project sourcing from China

Build a traceable Water treatment & desalination supply package

Share the design basis, system list, specifications, quantities, inspection plan, destination and delivery schedule.

Discuss the project