The non-standard M5/M6/M8 adjusting bolts and double-headed connecting screws formed by cold heading of 304 stainless steel are a kind of special fastener. The following are its customization requirements.
1. Basic product information
Material: 304 stainless steel, material certification is required, in compliance with GB/T 1220 standard
Specifications: non-standard customization, covering thread sizes such as M5, M6, M8, etc.
Type: double-headed connecting screw or adjusting bolt
Surface treatment: natural polishing or passivation, electroplating, sandblasting, etc. can be performed according to requirements
2. Technical requirements
Dimension tolerance:
Thread accuracy: 6g grade
Pipe diameter tolerance: ±0.02mm
Total length tolerance: ±0.5mm (special requirements need to be marked)
Mechanical properties: tensile strength ≥520MPa, hardness HRB 70-90
No cracks in the cold heading process, no missing teeth or burrs in the thread
Special structure: The adjusting bolt needs to be knurled or slotted/cross grooved
An anti-rotation plane or hexagonal structure can be added in the middle of the double-headed screw
3. Customization process
Demand confirmation: provide drawings or samples
Process review: confirm the feasibility of the cold heading mold
Proofing verification: provide 3-5 samples, cycle 5-7 days, fee negotiation
Mass production: after sample confirmation, delivery in 15-20 days (minimum order of 10,000 pieces)
4. Quality control
Testing items:
Thread go/no-go gauge test (100% full inspection)
Salt spray test ≥ 72 hours (on demand)
Material spectrum analysis (batch sampling)
Packaging requirements: PE bag + paper box (anti-scratch), or as specified by the customer
5. Notes
Non-standard products need to be clarified: thread direction (left/right), head chamfer, transition radius, and other details
304 stainless steel is not suitable for super acidic or alkaline environments, and the working conditions need to be stated in advance.
Through the coordinated optimization of materials, processes, and designs, this type of fastener is significantly superior to ordinary standard parts in precision, durability, and environmental adaptability, and is a key functional component in non-standard mechanical design.
