This is a high-precision bushing used in Chinese automotive applications within the Cummins system.

The material is 10B21 alloy steel. After heat treatment, the strength can reach Grade 10.9 standard. The surface is treated with zinc-nickel alloy plating, providing excellent corrosion resistance and extended service life.

The manufacturing process includes cold forging, precision machining, and knurling. Among them, cold forging is the key process control stage. It must achieve the required drawing dimensions as much as possible to minimize machining allowances, ensuring an optimal balance between cost and efficiency.

The product features are as follows:

• Single-side wall thickness: only 1.25 mm
• Flange thickness: only 1.25 mm
• Small size, thin-wall structure, high precision, and tight tolerances

During the knurling process, due to the thin wall structure, conventional two-roller knurling equipment may cause deformation. Therefore, a three-roller knurling machine must be used to form the diamond knurl pattern, ensuring dimensional stability and consistent surface texture.

Although the product has a complex structure and high forming difficulty, with extensive experience in non-standard cold forging parts and automotive precision components, Ningbo Yihu Hardware Manufacturing Co., Ltd. is able to maintain stable quality control and achieve reliable mass production.

Ningbo Yihu Hardware Manufacturing Co., Ltd.

Specializes in cold forged parts, custom metal parts, and automotive precision parts. We support OEM production based on drawings and samples, providing a one-stop solution from cold forming to precision machining.