Thread Rolling Defect Control Specification For M0.5~M2 Micro Precision Screws, Based On GB/T 196 Metric Thread Standard

M0.5~M2 ultra-fine micro screws are widely used in wearables, hearing aids and camera modules. Tiny thread burrs, root cracks and taper errors cause thread slipping and loose assembly after installation. This article provides standardized wire pre-treatment, rolling and full inspection rules based on GB/T 196 metric thread tolerance standard.

1. Causes Of Three Common Thread Rolling Defects

1. Thread edge burr: Worn thread roller tip or unremoved wire oxide scale forms metal flash during rolling; 2. Thread root micro-crack: Over-hard wire after annealing exceeds material yield strength under rolling extrusion; 3. Excessive thread taper deviation: Misaligned upper & lower rollers and uneven feeding speed.

2. Pre-treatment Standard For Micro Screw Wire

3. Full Inspection & Sorting Control Rules

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