
Our Internal Splined Steel Tubing is a high-precision, non-standard engineered solution designed for seamless mechanical coupling. Featuring a smooth circular exterior and a multi-toothed inner-serrated profile, this tube is the industry standard for high-torque transmission and anti-rotation assemblies.
Through advanced cold-drawing technology, we achieve superior dimensional accuracy in the internal geometry, eliminating the need for expensive internal broaching or machining.

High-Torque Performance: The multi-lobed internal ribs act as integrated keys, providing exceptional grip and power distribution.
Precision Cold-Drawn Finish: Achieves a high-grade surface finish and tight tolerances ($\pm 0.05mm - 0.1mm$), ensuring a perfect fit with mating shafts.
Enhanced Structural Integrity: Cold-working the steel increases its yield strength, making the splined profile more resistant to wear and deformation under heavy loads.
Custom Geometry: We offer 100% Bespoke Customization based on your CAD drawings, including tooth count, pressure angles, and wall thickness.
| Engineering Feature | Capability / Range |
| Profile Geometry | Internal Spline / Serrated ID / Star-shaped Interior |
| Material Grades | Carbon Steel (1020, 1045), Alloy Steel (4140, 5140), Stainless Steel |
| Manufacturing Process | Precision Cold Drawing / Mandrel Drawing |
| Surface Treatment | Bright Annealed, Anti-rust Oiling, or Phosphating |
| Key Function | Torque Transmission & Longitudinal Sliding |
Power Transmission: Telescoping drive shafts, PTO shafts for agricultural machinery, and industrial couplings.
Automotive Systems: High-precision steering columns, gear sleeves, and motorcycle transmission components.
Hydraulic Solutions: Specialized cylinder barrels requiring internal longitudinal grooves.
Construction Engineering: High-strength adjustable scaffolding joints and structural interlocking poles.
One-Step Manufacturing: By providing a ready-to-use internal profile, we help you bypass secondary machining processes, significantly reducing your production lead times and material waste. Our Craftsmanship ensures that every special-shaped tube is a reliable core for your mechanical equipment.
We are a professional steel tube manufacturer with over 30 years of experience, specializing in precision steel tubes, seamless steel tubes, PTO drive shaft tubes, and profiled steel tubes. With advanced production facilities and strict quality control, we provide reliable and customized tube solutions for industries including agriculture, automotive, and machinery.
Committed to quality, innovation, and customer satisfaction, we serve clients worldwide and strive to be a trusted global partner in steel tube manufacturing.
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