Aicaigou LogoAicaigou LogoB2B WikiIndustrial Encyclopedia

Locking Fastener Screw

Updated: 2026-07-24

Overview

Anti-loose screw fasteners are engineered solutions addressing vibration-induced loosening in mechanical assemblies. Unlike standard screws, they incorporate specialized thread designs, locking inserts, or chemical adhesives to maintain secure connections. These components are critical in industries where vibration or thermal cycling occurs, such as automotive manufacturing, rail systems, and heavy machinery. The technology dates back to WWII aircraft development, with modern variants including nylon patch screws, double-nut systems, and wedge-locking washers. Their performance is often validated through DIN 25201 or Junker vibration tests, ensuring reliability in demanding applications.

Structure and Working Principle

304不锈钢杯头内六角半牙螺丝M4圆柱头束尾点胶防脱螺栓深圳市正达盛科技有限公司

Common structural variants include prevailing torque nuts with deformed threads that create interference, two-piece flange screws with integrated washers, and screws with pre-applied thread-locking compounds. The locking action relies on either elastic deformation (nylon inserts) or mechanical interference (metal locking features). Advanced designs like the Nord-Lock washer system use wedge-effect technology, where tension increases with vibration rather than decreasing. Chemical locking methods employ anaerobic adhesives that cure in the absence of air, creating a secondary bonding layer between threads.

商家经验真实案例 · 安全可信
M4压铆螺母底孔指南
本文详解M4压铆螺母的底孔尺寸选择要点,包括常见材料适配孔径、钻孔技巧及安装注意事项,助你轻松解决紧固件安装难题。

Key Features

Vibration resistance is the primary characteristic, with some designs sustaining over 1,000 cycles in Junker tests. Material selection ranges from A2/A4 stainless steel for corrosive environments to high-strength alloy steels for heavy loads. Temperature resistance varies by type - nylon inserts typically withstand -40°C to +120°C, while all-metal designs can exceed 300°C. Reusability differs among types: chemical lockers are generally single-use, whereas mechanical lockers like distorted thread nuts can often be reused 5-10 times. Many industrial variants feature tamper-proof designs with breakaway heads or unique drive systems for security applications.

Application Areas

Transportation sectors account for 45% of usage, particularly in engine mounts, wheel assemblies, and aircraft structural components. Industrial machinery applications include pump couplings, conveyor systems, and press tools where constant vibration occurs. Renewable energy installations like wind turbines extensively use these fasteners in gearbox and blade attachment points. The construction sector employs them in seismic-resistant structures and bridge expansion joints. Emerging applications include robotics joints and medical device assemblies where micro-vibrations could compromise conventional fasteners.

Maintenance and Precautions

碳钢本色 U 型螺栓 管道固定U 形管卡螺丝 非标定制温州日一标准件有限公司

Periodic inspection should check for thread wear, nylon insert degradation, or adhesive failure. Re-torquing after initial installation is often recommended within 24-48 hours, especially for elastic-type lockers. Avoid mixing different locking systems (e.g., chemical and mechanical) unless specifically designed for compatibility. Storage conditions matter for pre-coated fasteners - humidity-controlled environments below 25°C preserve nylon insert elasticity and adhesive potency. Always clean threads before installation, as oil or debris can compromise locking performance by up to 30%.

商家经验真实案例 · 安全可信
柱间支撑安装要求
本文详细解析柱间支撑安装的核心要点,包括材料选择、安装步骤与质量控制,帮助工程人员实现稳定高效的施工效果。

B2B Procurement Guide

Industrial buyers should specify: vibration test requirements (e.g., DIN 65151), corrosion resistance standards (ASTM F1941 for chemical coatings), and acceptable reusability cycles. Bulk purchases of 10,000+ units typically offer 15-30% cost reductions, with MOQs varying by material grade. Quality certifications to verify include ISO 898-1 for mechanical properties and NASM 1312 for aerospace-grade fasteners. Lead times range from 2 weeks for standard stock items to 8 weeks for custom-engineered solutions. Consider vendor testing capabilities - reputable suppliers provide Junker test reports with each batch.

Related Manufacturers