描述

专业加长内六角三组合螺栓，由内六角圆柱头螺钉、平垫圈与弹簧垫圈通过一体化搓丝工艺成型，采用35K/40Cr高强度合金钢为主体材料，按DIN 912/GB/T 70.1标准生产，机械性能等级可达8.8级/10.9级，适配高负荷、长距离装配场景。

螺栓表面可按需提供白锌、黑锌、达克罗等多种防腐处理，经除氢工艺后，中性盐雾测试时长最高可达72-1000小时，有效抵御潮湿、酸碱及振动环境腐蚀；平弹垫一体化结构设计，可避免装配时漏装垫圈，同时通过弹簧垫圈的弹性形变实现持续防松，适配长期受力、高频振动工况。

加长规格覆盖M3-M16，公称长度支持定制化生产，螺纹精度达6g/6H级，牙型完整无毛刺，内六角头部采用冷镦成型工艺，受力均匀不易打滑，广泛应用于汽车底盘、工程机械、新能源设备、光伏支架及大型设备机架等对紧固可靠性、装配效率有严苛要求的领域。作为20年紧固件生产厂家，我们可提供拉力测试报告、盐雾测试报告及定制化表面处理服务，支持小批量试样与大批量订单生产。

This professional extended hexagon socket head triple combination bolt is integrally formed with a hexagon socket cap screw, flat washer, and spring washer via thread rolling process. Made of high-strength alloy steel (35K/40Cr), it is manufactured in accordance with DIN 912 / GB/T 70.1 standards, with mechanical performance grades up to 8.8/10.9, suitable for high-load and long-distance assembly scenarios.

Customizable surface treatments including zinc plating (white/black), Dacromet, and others are available. After hydrogen removal treatment, the neutral salt spray test duration can reach 72-1000 hours, effectively resisting corrosion in humid, acidic, alkaline, and vibrating environments. The integrated flat and spring washer design eliminates washer omission during assembly, while the spring washer provides continuous anti-loosening performance through elastic deformation, adapting to long-term stress and high-frequency vibration conditions.

Extended specifications cover M3-M16 with customizable nominal lengths, thread accuracy up to 6g/6H grade with complete, burr-free threads. The hexagon socket head is cold-forged for uniform force distribution and anti-slip performance. Widely used in automotive chassis, construction machinery, new energy equipment, photovoltaic brackets, and large equipment frames requiring strict fastening reliability and assembly efficiency. With 20 years of fastener manufacturing experience, we provide tensile test reports, salt spray test reports, and customized surface treatment services, supporting both small-batch samples and mass production orders.