Machined Spline Shaft Tube for Automotive Seats

A metal shaft structure featuring precision internal splines and multi-stage outer diameter steps, specifically designed for torque transmission and position locking in automotive seat adjustment mechanisms. The right end is equipped with a standard spline mating hole for engagement with the adjustment handle or drive gear, while the left side and middle section retain turned outer diameters and locating steps of varying sizes to ensure coaxial installation accuracy within the seat frame assembly.

The core of machining this part lies in ensuring the tooth profile accuracy and symmetry of the internal splines, as well as their positional relationship with external reference surfaces. Simultaneously, the surface roughness of the turned outer diameters must be strictly controlled to minimize assembly wear. Addressing the cutting characteristics of metallic materials, the manufacturing process focuses on controlling deformation after heat treatment and maintaining tolerance consistency for key mating dimensions, preventing assembly interference or loosening caused by stress release.

Leveraging Suzhou Shuangyue Precision Sheet Metal's IATF16949 and ISO 9001 certified systems, our factory is equipped with CNC lathes, milling machines, and CMMs, capable of handling various non-standard shaft parts from prototype verification to small-batch trial production. We combine blue light scanners for precise verification of spline profiles, support custom machining of materials such as carbon steel and stainless steel, and provide surface treatments like blackening and galvanizing to meet the corrosion resistance and appearance standards of the automotive零部件 industry.