Manufacturing Case Overview
Jinhua Machinery manufactures drawing-based automotive precision components. The primary case on this page is a carburized precision pin that requires controlled alloy-steel material, heat treatment, outside-diameter grinding and dimensional accuracy. The values shown apply to the documented example only. These values are case-specific and are not universal capability limits for new inquiries.
Component Information
- Component
- Precision Automotive Pin
- Primary case material
- 16MnCr5HH or ZF6 alloy steel
- Primary case heat treatment
- Carburizing to HRC 59–63 with a stated case depth of 0.5–0.8 mm
- Primary case drawing controls
- Outside-diameter tolerance of ±0.008 mm, roundness of 0.003 mm and surface roughness of Ra 0.2 μm
- Production basis
- Customer-approved drawing and project-specific technical review
Engineering Requirements
The released drawing governs material grade, heat-treatment condition, case-depth and hardness requirements, datum structure, outside-diameter size, geometric accuracy and surface quality. The primary published case requires precision control after carburizing and grinding. New inquiries are reviewed independently because material, section size, heat-treatment response, grinding allowance and inspection method can change the achievable result.
Manufacturing Challenges
- maintaining dimensional accuracy after heat treatment;
- controlling distortion and preserving the drawing-defined datum relationship;
- leaving sufficient and consistent grinding allowance;
- achieving the specified outside-diameter surface quality; and
- maintaining repeatable results across the approved production quantity.
Manufacturing Process
The primary case follows a drawing-reviewed route combining precision turning, carburizing coordination, outside-diameter grinding and inspection. The exact operation sequence, heat-treatment controls, intermediate allowances and inspection frequency are confirmed from the released drawing and project requirements.
Additional Redacted Drawing Reference
A second customer-supplied pin drawing confirms a separate carbonitrided steel reference. It is intentionally kept separate from the carburized primary case: its material, thermal process and acceptance values are not presented as interchangeable.
- Reference material
- SAE J403 Grade 1215 carbon steel
- Verified process route
- Combined stock cutting → first-end face and center-hole machining with rough outside-diameter turning → opposite-end center-hole machining and finish outside-diameter turning → carbonitriding → outside-diameter grinding
- Heat treatment
- Carbonitriding, quenching and tempering
- Case-depth requirement
- Total case depth after grinding: 0.25–0.50 mm
- Surface-hardness requirement
- HR15N 86.5–89.0 after grinding
Quality Control
Inspection planning follows the released drawing. Applicable controls include material verification, dimensional and geometric inspection, hardness inspection, case-depth verification, outside-diameter surface inspection and final drawing-compliance review. Sampling, instruments, acceptance criteria and report format are confirmed for each project.
Review precision component quality inspection capabilities.
Related Capabilities
Review CNC machining process planning, use the Precision Component Quality Inspection page, or browse the Manufacturing Cases directory.
Request a Quote
Send the current drawing and revision, material specification, order quantity and annual demand, critical dimensions and datums, heat-treatment requirements, hardness and case-depth criteria, surface-finish requirements, inspection and reporting needs, traceability, packaging and target delivery date.