Home / Capabilities / Quality Control Process

The Jingbang Quality Control Framework: A Step-by-Step Process

Our quality framework is a closed-loop system designed to prevent defects rather than just detecting them. It follows the part from initial design review through to final shipment.

DFM & Technical Review
📐

1. DFM & Technical Review

Before any material is cut, our engineering team conducts a thorough review of your design files:

  • Design Validation: Assess drawings and CAD models for clarity and manufacturing challenges
  • Material & Finish Analysis: Verify specifications for intended application
  • Tolerance Assessment: Identify critical dimensions and flag areas requiring special attention
Material Certification
📜

2. Material Certification & Traceability

Quality begins with verified materials:

  • Supplier Vetting: Qualified raw material suppliers with ongoing performance monitoring
  • Material Verification: All incoming material checked against purchase order
  • Full Traceability: Material certifications from manufacturer — traceable grade, origin, and compliance (RoHS, REACH)
In-Process Quality Control
⚙️

3. In-Process Quality Control (IPQC)

Continuous monitoring to maintain stability and precision:

  • First Article Inspection (FAI): Full dimensional inspection before mass production
  • Process Monitoring: CNC probes and sensors provide real-time feedback
  • Scheduled Checks: IPQC operators monitor critical dimensions to prevent process drift
Final Inspection
🔬

4. Final Inspection & QA

Rigorous final inspection before shipment:

  • Dimensional Inspection: CMMs, optical comparators, thread gauges
  • Visual & Functional Inspection: Cosmetic requirements, surface finish, burrs
  • Comprehensive Reporting: Formal inspection reports with CMM data and material certifications

Manufacturing Tolerances & Standards

Clarity on tolerances is crucial. Unless otherwise specified on a technical drawing, we adhere to the ISO 2768-1 standard for general tolerances.

Limits for Nominal Size Metals – Medium Class (m) Plastics – Coarse Class (c)
0.5mm* to 3mm±0.1mm±0.2mm
>3mm to 6mm±0.1mm±0.3mm
>6mm to 30mm±0.2mm±0.5mm
>30mm to 120mm±0.3mm±0.8mm
>120mm to 400mm±0.5mm±1.2mm
>400mm to 1000mm±0.8mm±2.0mm

*Note: For dimensions under 0.5mm, tolerances must be individually specified. For tight tolerances that exceed ISO 2768-m (e.g., ±0.01mm), critical dimensions must be clearly indicated on a technical drawing.

Our Quality Guarantee & Resolution Process

We stand behind our work. If any part of your order does not meet the agreed-upon specifications, we will act promptly.

🔧

Rework

For parts with processing defects or that fall outside tolerance, we will immediately initiate rework to bring them into compliance.

💰

Refund

If the parts are unusable or you prefer not to proceed with rework, we will process a refund or credit after confirming the issue.

⏱️

Notification

Should you encounter any quality concerns, please notify our team within 5 business days of receipt, and we will provide a resolution plan within 1-3 business days.

Industry Standards & Technical Resources

For official information on international standards, visit the official International Organization for Standardization (ISO) website.

Request Quality Documentation →
ISO 9001

Frequently Asked Questions

Expert answers about our quality control process.

1. What is the difference between Quality Control (QC) and Quality Assurance (QA)?
Quality Control (QC) is the inspection and testing process used to verify that a product meets specified requirements. Quality Assurance (QA) is the broader system of planned activities and processes that ensure quality is built into the product from the start. In short: QC finds defects, QA prevents them.
2. Can I get a material certificate for my order?
Yes. We can provide full material certifications (Mill Test Reports / MTRs) and Certificates of Conformance (CoC) for all parts we manufacture. Please specify this documentation requirement when you submit your RFQ.
3. What standard tolerances do you follow if none are specified on my drawing?
If no tolerances are specified on your drawing, we follow ISO 2768-1 general tolerances. For metals, we apply the "Medium" class (m); for plastics, we apply the "Coarse" class (c). We always recommend specifying critical dimensions directly on your drawing.
4. What is a First Article Inspection (FAI) Report?
An FAI Report is a comprehensive dimensional inspection of the first part produced from a new production run. It verifies that all critical dimensions, materials, and finishes meet the drawing specifications before mass production begins. We provide FAI reports as part of our quality documentation.
5. What certifications does your manufacturing network hold?
Our quality management system is ISO 9001:2015 certified, and we actively support IATF 16949 requirements for automotive applications. We also comply with RoHS and REACH regulations. Additional certifications can be provided upon request.

Ready to Ensure Quality in Your Next Manufacturing Project?

Upload your specifications. Our quality team will provide DFM feedback and a comprehensive quality plan — including inspection protocols and reporting — within 24 hours.

Request a Quote → Talk to a Quality Engineer

📁 Accepted formats: STEP, IGES, PDF | 📋 Include critical dimension callouts, required tolerances, material specifications, and any certification requirements (ISO 9001/IATF 16949) | ⚡ DFM feedback in ≤24 hours | 🔧 ISO 9001:2015 certified — full traceability and inspection reports

cd-machining.com is a brand of JingBang Tech — Visit our main site →