Shanghai Zhengao automotive co., Ltd , built in 2009, produces professionally 30° variable tooth type locking thread tap, gauge, nut and self-locking thread tools. Its locking thread products, produced by using the advanced technology, can be used repeatedly, simple structure, convenient use and wide scope of application with locking reliable performance.

    The locking thread technology of 30° variable tooth  type , widely used in railway, port machinery, automobile, engineering machinery, bridge, has been widely applied in the ministry of railways locomotive plant, Shanghai Zhenhua Heavy Industries、China Faw Group Corporation、Dongfeng Motor、SAIC Motor、Yudong、China National Heavy Duty Truck Group Co., LTD、Shaanxi Hande Axle Co., Ltd、Guangxi Fangsheng、Shaanxi Automobile Group Co., Ltd、Shanghai Diesel Engine Company Lim and so on. 

    Although sustained development, Shanghai Zhengao has become a company which takes 30° variable tooth type locking thread technology as the core, included locknut, production equipment of locking thread tool, tapping equipment of thread nut and testing equipment of a full range of thread product. It lays the first domestic quite position at product research, manufacturing, testing and applications of 30° variable tooth type locking thread. 

    Shanghai Zhengao which has a number of national patents focus on the combination of the research of high tech and product applications. The company‘s 30° variable tooth type locknut product won the Shanghai high-tech achievement transformation project certificate in 2010.

    Shanghai Zhengao respectively gets through the quality system certification of IS0900L: 2000 and TS16949: 2002 in 2010 and 2011. 30°variable tooth type locknuts produced by Shanghai Zhengao complies Railways standard TB/T 3019-2001 and the Ministry of Machinery Industry standard JB/T10971-2010.