Importance of First Article Inspection
In 3D printing services, first article inspection is an important control point for preventing batch quality issues. Through first article inspection, problems in process, equipment, materials, and other aspects can be identified before mass production, avoiding the appearance of a large number of nonconforming products after batch production. It is an important means of quality cost control. This article systematically explains the process and methods of first article inspection from four dimensions: first article definition, inspection items, acceptance criteria, and batch release.
Definition and Scope of First Article
1. First Article Definition
A first article refers to the first piece or first batch of products produced under formal production conditions when a new product is introduced into production, the process is changed, equipment is repaired, materials are replaced, etc. First article inspection is a comprehensive inspection and confirmation of the first article to ensure that the production conditions can consistently produce qualified products.
2. Trigger Conditions for First Article Inspection
| Trigger Condition | Specific Scenario | No. of First Articles |
|---|---|---|
| New product launch | First time producing this product | 1-5 pcs |
| Process change | Process parameters or process route changed | 3 pcs |
| Material change | Changing material batch or supplier | 3 pcs |
| Equipment maintenance | Replacement of key components or overhaul | 3 pcs |
| Equipment changeover | Switching from one machine to another | 3 pcs |
| Resumption after production stoppage | Resuming production after a period of stoppage | 3 pcs |
| Customer requirement | Customer explicitly requires first article inspection | As required by customer |
3. Determining the Scope of First Article Inspection
- Inspection items: Determine inspection items based on product characteristics
- Inspection quantity: Determine the number of first articles based on risk level
- Inspection timing: Conduct first article inspection after production conditions are stable
- Inspectors: Performed by qualified inspection personnel
- Inspection equipment: Use calibrated testing equipment
Inspection Item Design
1. Appearance Inspection Items
| Inspection Item | Inspection Content | Inspection Method | Inspection Tool |
|---|---|---|---|
| Surface quality | Surface roughness, surface defects | Visual inspection + touch | Roughness tester, magnifying glass |
| Color | Color consistency, color difference | Visual comparison | Colorimeter |
| Deformation | Warping, twisting, deformation | Measurement | Platform, height gauge |
| Defects | Cracks, pores, inclusions, lack of fusion | Visual inspection + nondestructive testing | Magnifying glass, CT |
| Support residue | Whether support removal is clean | Visual inspection | Magnifying glass |
2. Dimensional Inspection Items
- Key dimensions: Critical feature dimensions that affect function
- Important dimensions: Important dimensions that affect assembly
- Overall dimensions: Overall part dimensions
- Fit dimensions: Dimensions that affect fit
- Geometric tolerances: Flatness, roundness, position tolerance, etc.
3. Performance Inspection Items
- Mechanical properties: Tensile, impact, and other tests as required
- Functional test: Functional testing as required
- Sealing performance: Parts requiring sealing
- Pressure resistance: Parts with pressure requirements
- Other special requirements: According to customer requirements
4. Process Parameter Inspection
- Print parameter confirmation: Confirm that the actual printing parameters are consistent with the process documents
- Process data check: Check whether the printing process data is normal
- Material batch confirmation: Confirm that the material batch used is correct
- Equipment status confirmation: Confirm that the equipment status is normal
Formulation of Acceptance Criteria
1. Sources of Acceptance Criteria
- Design drawings: Dimensional tolerances, geometric tolerances, and technical requirements indicated on the drawings
- Technical agreement: Technical requirements agreed with the customer
- Industry standards: Industry standards or national standards
- Internal standards: Quality standards established internally by the company