Non-standard screws play a crucial role in modern industrial production, and ensuring their quality is paramount. To maintain high standards, it’s essential to follow strict acceptance criteria during production and inspection. So, what are the key acceptance standards for non-standardized screws?

1. Surface Defect Standards
Non-standard screws, as an evolution of standard screws, should adhere to the same surface defect standards outlined for standard screws. It is important to identify specific inspection items according to national standards. If surface coatings or plating interfere with defect detection, these should be removed before inspection. Refer to the relevant national standards for detailed guidelines.

2. Dimensional and Material Inspection
Non-standardized screws must be inspected for dimensions and material in accordance with the design specifications. Material inspection is crucial, and manufacturers should provide material certificates. High-end products should also include SGS material certification and undergo component analysis in accredited laboratories to confirm that material compositions meet the design requirements.

3. Non-Destructive Testing
Non-destructive testing (NDT) is essential to ensure that non-standardized screws meet functional requirements without damaging them. During NDT, any signs of quenching cracks, surface wrinkles, or other defects should be identified. Additionally, the coating must comply with RoHS environmental standards. Ensuring these aspects helps verify that the screws are fit for their intended application.

4. Destructive Testing
Destructive testing involves tests that can damage the screws but are crucial for verifying their quality. This includes hardness testing, internal hardness measurements, mechanical performance assessments, and torque tests. Although these tests may damage the screws, they are necessary for custom-designed screws manufacturers committed to high-quality standards to ensure the custom-designed screws meet all performance criteria.

In summary, the acceptance standards for non-standard screws encompass surface defect criteria, dimensional and material inspections, non-destructive and destructive testing. Adhering to these standards ensures that non-standard screws meet quality, safety, and performance requirements, ultimately leading to reliable and effective use in various applications.