Duplex Stainless Steel: Qualifying a New Casting Supplier

For buyers reviewing duplex stainless steel, a useful specification connects the service, the approved drawing and the delivered component. This guide examines the purchasing question “Qualifying a New Casting Supplier”. Use it to organize the supplier discussion before approving material, tooling or production.

Key purchasing decisions for duplex stainless steel

Duplex stainless steel combines ferritic and austenitic phases, so chemistry alone does not establish an acceptable casting. Supplier qualification should connect the specified grade, heat treatment, section geometry and inspection evidence. The objective is repeatable production of the required condition, not merely a compliant alloy name.

Review the design and interfaces

Identify the thickest sections and abrupt junctions on the component. Discuss how the foundry will achieve the required treatment throughout the geometry. Keep proposed weld repairs and subsequent thermal operations within the agreed manufacturing plan.

Compare the purchasing options

Use this comparison when reviewing duplex stainless steel against a controlled drawing and purchase specification.

Select the manufacturing route

Discuss the geometry and material requirements before tooling is frozen. Thick bosses, thin adjoining walls and enclosed regions can need different production attention. The foundry should explain its proposed route and evidence package, while the design authority approves material and acceptance requirements.

For a project involving duplex stainless steel, compare the complete delivered condition before choosing a production route.

Inspection requirements for duplex stainless steel

Agree required chemical, mechanical, microstructural and corrosion-related checks with the design authority. Record where samples come from and when tests occur. The inspection package should demonstrate the ordered requirements without assuming one test proves everything.

Apply the review to a practical case

For a new pump-body supplier, first-article approval should cover production-representative material and processing. A separately prepared display sample cannot establish consistency for a heavier or differently shaped casting.

Define a complete quotation scope

Include the approved casting grade and specification, section geometry, service environment, machining scope and required tests. State the sampling and acceptance basis rather than requesting a generic duplex certificate. Identify proposed substitutions or repairs as items requiring the agreed technical review.

When discussing duplex stainless steel, separate requirements already approved by engineering from options still awaiting review.

For background reading, see IMOA practical guidelines for duplex stainless steels. Use the applicable project specification and approved design for contractual requirements.

Discuss the component with Leierwo

Review Leierwo’s Fundición de acero inoxidable y Fundición de inversión pages, then send the controlled drawing, material and quantity for a component-specific discussion. Ask the quotation to state the manufacturing scope, inspection evidence and any proposed alternatives.

Frequently asked questions