The shims and non-standard stud screws used in 12.9-grade CNC turning tool bar accessories are key functional components in precision machining. The following describes their customization requirements.
1. Basic Parameters
Material: 12.9-grade alloy steel
Surface treatment: Blackened/nickel-plated/Dacromet (selectable based on corrosion protection requirements; blackened is the default).
Hardness: HRC 39-44 (ensuring a balance of high strength and toughness)
Thread specification: Non-standard stud thread.
Thread accuracy: 6g grade
Total length: Customized based on shim thickness
2. Structural Design
Head type: External hexagonal or cylindrical flat head at both ends.
Transition section: The intermediate polished rod diameter must be smaller than the thread minor diameter to avoid interference.
Undercut groove: An undercut groove is machined at the end of the thread.
3. Special Requirements
Anti-loosening Treatment: Optional thread sealant pre-coating or locking grooves are available.
Marking: Laser marking of material grade (12.9) and specification (e.g., M5-M6)
Packaging: Rust-proof oil + vacuum bagging, 50 pieces/box (or as per customer's request)
4. Inspection Standards
Dimensional Inspection: Thread verification with go/no-go gauges, key dimensions measured with three-dimensional coordinate measurement
Performance Testing: Tensile and torque testing are performed on random samples.
Salt Spray Test: The coating must pass a 48-hour neutral salt spray test (optional).
5. Delivery and After-Sales Service
Sample Lead Time: 3-5 business days (3 free samples provided)
Bulk Delivery: 15-20 days (order quantity > 1000 pieces)
Warranty: Free replacement within 12 months due to material defects
A toolholder interface drawing or physical sample is required to ensure compatibility between the non-standard screw and the shim/toolholder.
Through the above design, the two together ensure the reliability of CNC tools in high-load processing, which is especially suitable for precision manufacturing fields such as aerospace, molds, etc.
