About Us

Haimen City Mingzhu Steel Ball Co., Ltd.

Founded in 1992 in China, Haimen Mingzhu Steel Ball Co., Ltd. is a professional manufacturer of precision steel balls with more than 30 years experience. The company is located in Haimen City, easily reachable thanks to the immediate vicinity of the Shanghai metropolitan region. It has an area of 7,000 m2, with an annual output of 3,500 tons. We specialize in producing chrome steel ball, stainless steel ball and carbon steel ball ranged from diameter 2.0mm to 50.0mm, grade G10-G500, which are commonly used in precision equipment such as: ball bearings, ball screw sliders, automotive parts, medical equipment, fluid valves and cosmetic industry.


More than 30 years experience in steel balls making.


Annual output of more than 3,500 tons.


More than 300 tons of stocked products available.

Company Certificate

The company obtained the ISO9001 management system certification in 2008 and the IATF16949 automotive industry quality management system in 2016. It has 21 national “Utility model patents”.


Quality Control

Since the establishment, we have consistently adhered to the principle of quality assurance, and put the quality of products in the most important position. A complete management system was established, especially the inspection and tracking system from raw materials to finished products.
The company has a complete set of sophisticated inspection instruments: photoelectric surface defect detector, Rockwell hardness tester, Vickers hardness tester, roughness meter, roundness meter, diameter comparator, metallographic microscope, vibration detector and crush load machine. The technical parameters of each batch of steel ball are well measured to make sure that the product meets the quality requirements of the customer.


Contact Us

We provide you with intensive consultation and advice before production to help you find the best product for your needs. We are getting poised for the challenge of gaining the satisfaction of all customers through a continuous improvement of our products and service.