Specializing in the production of special precision screws and nuts of various standards such as Chinese standard GB, Japanese standard JIS, British BS, American ANSI and ISO.
At present, the smallest screw diameter that our company can produce is 0.4mm, the shortest is 0.4mm, and the longest is 300CM.
2025-06-14 16:41:41
A set screw with ball tip is a specialized fastener designed to secure an object within or against another object, featuring a spherical (ball) tip at its contact end. This design provides distinct advantages in applications requiring precise positioning, reduced surface damage, and improved torque transmission.
Key Technical Characteristics:
Material Composition: Typically manufactured from alloy steel (Grade 8.8 or 12.9), stainless steel (A2/AISI 304 or A4/AISI 316), or brass, with hardness ranging from 28-45 HRC for steel variants.
Ball Tip Diameter: Standard sizes range from 1.5mm to 12mm, with ±0.05mm tolerance for precision applications.
Surface Treatment: Common finishes include zinc plating (5-15μm thickness), black oxide (Fe₃O₄ coating), or electroless nickel plating (10-50μm).
Torque Capacity: M4 size (steel): 2.5-3.5 Nm; M8 size: 20-28 Nm (varies by material and thread engagement).
Temperature Range: Standard materials: -50°C to +120°C; high-temp variants up to +600°C with special alloys.
| Parameter | Specification |
|---|---|
| Thread Standards | Metric (ISO 898-5), UNC/UNF (ASME B18.3), with pitch accuracy class 6g for metric threads |
| Ball Hardness | HRC 58-62 (carburized or hardened steel balls) |
| Concentricity | ≤0.05mm TIR (Total Indicator Reading) for precision applications |
| Corrosion Resistance | Salt spray test: 96-500 hours depending on coating (ASTM B117) |
| Drive Types | Hex socket (ISO 4762), slotted (ISO 1207), or Torx (ISO 10664) |
Set screws with ball tips find application in numerous industrial and mechanical scenarios:
Precision Machinery: Used in optical equipment alignment systems where the ball tip provides smooth surface contact with minimal marring (surface pressure < 500 MPa).
Automotive Components: In throttle linkage adjustments and transmission shift mechanisms, offering vibration resistance up to 15G acceleration.
Medical Devices: For adjustable components in imaging equipment, utilizing AISI 316L stainless steel for biocompatibility (ISO 13485 compliant).
Robotics: In joint tensioning systems, with cycle life exceeding 50,000 adjustments without significant wear.
Electronics Manufacturing: For PCB fixturing where ESD-safe materials (surface resistance 10⁶-10⁹ Ω) are required.
Aerospace: In control surface mechanisms, meeting NASM 25027 specifications for high-strength applications.
Proper Installation Procedure:
Clean both the screw threads and mating surface (surface roughness Ra ≤ 3.2 μm recommended)
Apply thread locker (e.g., Loctite 243 for medium strength) if vibration resistance is required
Use a torque wrench calibrated to ±5% accuracy of target torque value
Tighten to 75% of final torque, then make final adjustment in 5% increments
For critical applications, measure clamp force using ultrasonic tension measurement (accuracy ±1% of reading)
Proper maintenance ensures optimal performance and longevity:
Lubrication: Use molybdenum disulfide grease (ISO VG 68) for high-load applications, reducing friction coefficient by 30-40%.
Inspection Interval: Visual inspection every 500 operating hours; torque verification every 2,000 hours or per manufacturer's guidelines.
Corrosion Prevention: For marine environments, apply corrosion inhibitor (e.g., Tectyl 506) with minimum 50μm dry film thickness.
Wear Measurement: Monitor ball tip diameter reduction using optical comparators; replace if wear exceeds 5% of original diameter.
Replacement Criteria: Replace screws showing thread deformation >10% of pitch diameter or any visible cracks (magnified 10x inspection).
For demanding applications, consider these factors:
Thermal Expansion: Coefficient of thermal expansion mismatch (e.g., steel screw in aluminum housing: Δα ≈ 12×10⁻⁶/°C) requires torque adjustment at temperature extremes.
Gall Prevention: For titanium alloys, use anti-galling compounds (e.g., Molykote P37) to reduce cold welding risk.
Fatigue Life: In cyclic loading (10⁶ cycles), maintain stress below 30% of tensile strength for infinite life design.
Electrical Isolation: For EMI-sensitive applications, consider nylon-tipped variants with dielectric strength >20 kV/mm.
Copyright © 2025 Dongguan CHEKSINE Metal Technology Co., Ltd. All Rights Reserved
