1. Why an Audit Is Essential

A paper-based evaluation - certifications, brochures, website, even marketing videos - tells you only part of the story. The real picture emerges when you step onto the factory floor. A physical or virtual audit reveals the actual state of equipment, the discipline of processes, the cleanliness of the facility, and the competence of the team.

Many buyers skip the audit step, especially when the foundry looks good on paper. This is a mistake. We have seen cases where a foundry with excellent certifications was later found to be using expired calibration standards, running shell building in an uncontrolled environment, and skipping inspection steps. The audit catches these problems before they become your problems.

This guide walks through a structured audit process with specific checklists for each area of a casting foundry.

2. Pre-Audit Preparation

A successful audit starts before you arrive at the factory. Proper preparation ensures you use your time effectively:

Document Review (Before the Visit)

Send a pre-audit questionnaire covering: certifications, equipment list, client references, quality system documentation

Request and review the quality manual, control plan (for your part type), and process flow diagram

Review any previous audit reports (internal or external) and their corrective actions

Prepare a list of your specific requirements: materials, tolerances, NDT, testing, documentation

Define the scoring system you will use - consistent scoring across multiple candidates enables objective comparison

Logistics Preparation

Confirm the audit schedule and agenda with the foundry in advance

For in-person: bring a camera, measuring tools (caliper, tape), flashlight, and your checklist

For virtual: confirm internet connectivity, camera availability, and that key personnel will be present

Request that the quality manager and production manager be available during the audit

3. Audit Area 1: Quality Management System (QMS)

Start in the conference room with a documentation review. The QMS is the foundation - if the documentation is weak, the execution likely is too.

Documents to Review

Quality manual: scope, approval authority, document hierarchy

Document control procedures: version control, distribution, obsolete document management

Internal audit records: frequency, scope, findings, and corrective actions

Management review meeting minutes: evidence that top management reviews quality performance

Training records: calibration training, NDT certification, technical training for production staff

Calibration records: all inspection and test equipment with current certificates

Non-conformance records: NC reports, root cause analysis, corrective action (8D) reports

Customer complaint log: complaints received, actions taken, trends over time

Score 1-5: 1 = documentation incomplete or missing; 3 = adequate documentation with minor gaps; 5 = comprehensive, current, and well-organized documentation system.

4. Audit Area 2: Production Floor

This is the most important part of the audit. Walk the production floor systematically from raw material to finished product.

Raw Material Storage

Observe: Are different material grades segregated and clearly labeled? Is there a traceability system (heat numbers, batch numbers)? Are materials stored away from moisture and contamination? A well-organized material storage area is a reliable indicator of overall process discipline.

Wax Injection Area

Observe: Temperature and pressure gauges on injection machines. Die storage and maintenance condition. Wax pattern handling and storage (patterns should be stored at controlled temperature to prevent distortion). Are operators following documented work instructions?

Shell Building Area

Observe: Slurry viscosity control (measured and logged). Temperature and humidity in the shell building room (should be controlled). Dip tank condition and maintenance. The number of coats applied. Drying time between coats. Shell handling - are shells handled carefully to avoid damage?

Melting and Pouring

Observe: Furnace condition and maintenance records. Temperature control during melting. Spectrometer verification of each melt before pouring. Pouring practice - is it controlled or haphazard? Shell preheat temperature prior to pouring. Safety equipment and practices.

Fettling and Finishing

Observe: Gate removal methods (grinding, cutting). Surface grinding and blending quality. Workmanship standards - are operators inspecting as they work? The general cleanliness of the finishing area.

CNC Machining

If the foundry offers CNC machining: observe machine maintenance records, tool control system, coolant condition, and chip management. The CNC area should be organized and clean - this is a proxy for machining quality.

Production floor observation is the heart of a successful factory audit

5. Audit Area 3: Laboratory and Inspection

The QC laboratory reveals the foundry's commitment to quality verification.

What to Check

Spectrometer (OES): Make and model (German SPECTRO is the gold standard). Last calibration date. Calibration standard used. Check that they test every melt, not random samples.

CMM (Coordinate Measuring Machine): Make and model. Environmental temperature control. Inspection programs available for review. Calibration status of the CMM and its probe.

NDT equipment: Dye penetrant station (check chemical expiration dates). X-ray equipment (if applicable, check radiation safety compliance). Ultrasonic testing equipment.

Mechanical testing: Tensile test machine with current calibration. Hardness tester (Rockwell, Brinell). Sample preparation equipment.

Metallographic microscope: For microstructure analysis and grain size verification.

Equipment	What It Verifies	Gold Standard	Red Flag
Spectrometer (OES)	Chemical composition	SPECTRO / ARL	No spectrometer or uncalibrated
CMM	Dimensional accuracy	Zeiss / Hexagon	No CMM or uncontrolled environment
Tensile tester	Mechanical properties	Zwick / Instron	No tensile testing capability
NDT (PT/RT/UT)	Surface & internal defects	In-house capability	No NDT or outsourced only
Hardness tester	Hardness compliance	Rockwell + Brinell	No hardness tester available

6. Audit Scoring System

Use a consistent scoring system across all audit areas to compare candidates objectively:

Score	Rating	Description
5	Excellent	Exceeds requirements. Best practices observed. No improvement needed.
4	Good	Meets requirements. Minor opportunities for improvement identified.
3	Acceptable	Meets minimum requirements. Some gaps identified that need corrective action.
2	Below average	Multiple gaps requiring corrective action before production can begin.
1	Unacceptable	Significant deficiencies. Do not proceed with this supplier.

Overall score: A weighted score of 4.0+ is excellent - proceed with confidence. 3.5-4.0 is acceptable with monitoring. Below 3.5 requires corrective action before proceeding. Below 3.0 means disqualify.

Frequently Asked Questions

Q: Can I do a virtual audit instead of in-person?

A: Yes. A structured video call walkthrough can be effective for initial evaluation. However, an in-person audit is strongly recommended before committing to large-volume production orders.

Q: How long should a casting foundry audit take?

A: A thorough audit takes 4-6 hours including: documentation review (1 hour), production floor walkthrough (2 hours), lab inspection (1 hour), and closing meeting (30 minutes).

Q: What if the foundry refuses an audit?

A: Consider this a major red flag. No legitimate, quality-focused foundry will refuse a properly scheduled audit from a serious buyer. Disqualify them.

Q: How many people should be on the audit team?

A: 2-3 people ideally: a quality engineer, a procurement specialist, and potentially a design engineer. If only one person, ensure they have both technical and procurement experience.

Q: How often should I re-audit an existing supplier?

A: Annually is standard. For critical suppliers or after quality incidents, a more frequent audit schedule may be appropriate.

Ready to Audit Our Foundry?

We welcome audits at WUDI COUNTY SHUN YE STAINLESS STEEL PRODUCTS CO., LTD. Whether in-person or virtual, you will find a well-organized facility with certified quality systems and experienced personnel.

Schedule your audit: sales@wdshunye.com

WUDI COUNTY SHUN YE STAINLESS STEEL PRODUCTS CO., LTD.

Phone: +86-17754343500 | Email: sales@wdshunye.com | https://www.shunyecasting.com

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How to Conduct a Casting Supplier Audit