Founded in 2002, Shandong Zhiheng Vibration Damping Tech. Co., Ltd.(formerly Shandong Ningjin Spring Co., Ltd.) is an assigned manufacturer by the Chinese Ministry of Railways. The production code is DNJ. We specialize in all kinds of cold and hot coiled springs with diameter ranging from 0.1mm to 90mm, especially railway, engineering and mine mechanism and vehicle springs. Our main products include compression springs, extension springs, heavy duty extension springs, precise extension springs, power springs, heavy duty torsion springs, precise torsion springs, and wire formed and metal stamped products.In order to meet the requirements of all customers, Ningjin Spring has established 4 new standard automatic spring production lines. Our spring molding uses intermediate frequency influence heating furnace, and heat treatment uses resistance furnace which are controlled by computers. Now we have 12 sets of various kinds of electric furnaces, 6 automatic spring coiling machines, 4 shot blasting machines, 6 spring testers and a set of spring electrostatic spraying and japanning drying equipment. We own all kinds of production facilities and testing apparatus.To attain most perfect quality, Ningjin Spring passed ISO9001 quality assurance system in 2002. The goods we offered to customers have been warmly welcomed and appreciated for their high quality. It is our only tenet to meet your requirements and give you satisfied goods and services.

Picture	Certification Name	Certified By	Business Scope	Available Date --- Expired Date	Verified
	Other	SGS	Manufacturing and Maintenance	2018-11-08 ~ 2021-10-30	Verified
	ISO9001	SGS	Design and development, manufacturing, maintenance of steel springs for railway vehicle; Design and development, manufacturing of rubber parts for railway vehicle	2018-11-08 ~ 2021-10-30	Verified
	ISO/TS16949	IATF	MANUFACTURE OF COLD COILED SPRING	2013-04-26 ~ 2014-06-26
	ISO9001	IATF	MANUFACTURE AND SERVICE OF HOT FORMING HELICAL COMPRESSION SPRING FOR LOCOMOTIVE AND ROLLING STOCKS	2013-04-26 ~ 2014-08-28
	ISO9001	Issued by the SEA TONE.	Manufacture and service of hot forming helical compression springs for locomotive and rolling stocks.	2006-10-12 ~ 2009-10-11
	IRIS Certificate	Dekra	Design, development and manufacturing of spring for railway rolling stock	2013-09-08 ~ 2016-09-07

Business Type	Manufacturer, Trading Company	Country / Region	Shandong, China
Main Products	Spring, Rubber Products	Ownership	Private Owner
Total Employees	301 - 500 People	Total Annual Revenue	confidential
Year Established	2005	Certifications(2)	ISO9001, Other
Product Certifications(1)	Test Report	Patents	-