

Ningbo Dongding Special Tube Co., Ltd. (Dongding) is a leading Chinese manufacturer specializing in the R&D and production of ultra-long precision stainless steel tubes. The company is a subsidiary of Zhenhai Petrochemical Jianan Engineering Co., Ltd., which was formerly a wholly-owned subsidiary of Sinopec Zhenhai Refining & Chemical Company.
Focused on high-end special tubes for the petrochemical and aerospace industries, Dongding is a national high-tech enterprise and a Specialized and Sophisticated SME based in Ningbo. It has a Zhejiang Provincial Enterprise Research Institute and a CNAS-accredited Testing Center, with full-chain technical capabilities from R&D to testing.
Equipped with China’s top-tier high-speed precision cold-rolling (drawing) seamless tube lines and industry-leading multi-station automatic welded tube lines, we deliver ultra-long tubes with exceptional precision.

The company maintains certifications for QEO systems, GJB 9001C, IATF 16949, EU PED, CCS, a TS special equipment license, and CNAS laboratory accreditation.
It owns 9 invention patents, 18 utility model patents, and 2 software copyrights, with core technologies spanning cold rolling, heat treatment, and testing. Long-term industry-university-research partnerships have been established with Sinopec ZRCC, ZPC, Ningbo University, Ningbo University of Technology and etc.
Leveraging its strengths in the petrochemical sector, the company is advancing into new energy, environmental protection, and high-efficiency technologies, while expanding into aerospace, nuclear power, and other emerging fields.
Guided by the principles of "Righteousness, Integrity, Innovation, Precision, and Harmony," Dongding is committed to becoming a respected industry leader and contributing to a resource-conserving and eco-friendly society.
