Precision Robot Telescopic Arm Inner Tube Hard Anodizing Processing High Straightness Grinding Polishing Case Study

This case study details the complete machining process for a telescopic arm inner tube used in a food service robot. Through a stringent series of processes including "precision extrusion -> rough and fine straightening -> CNC precision turning -> hard anodizing -> micron-level sealing," we overcame technical challenges such as the easy deformation of long thin-walled tubes and difficult control of oxide layer uniformity. The final product fully met the customer's high standards for straightness, surface hardness, and wear resistance.

1. Precision Extrusion: Using 6061-T6 aluminum alloy billet, precision extrusion is performed under constant temperature conditions to obtain the initial tube profile, strictly controlling outer diameter and wall thickness tolerances.



2. Multi-pass Straightening: Rough and fine straightening are carried out through multiple sets of straightening rollers to gradually eliminate internal stresses generated during extrusion and cooling, ensuring tube straightness ≤0.15mm/m.



3. CNC Precision Turning: High-precision CNC lathes are used for finish machining of the tube's outer circle, further correcting straightness and ensuring dimensional tolerance, providing a uniform substrate surface for subsequent anodizing.



4. Hard Anodizing: Hard anodic oxidation is performed in a low-temperature (-5~0°C), high-current-density electrolyte. Bath concentration, temperature, and oxidation time are precisely controlled to ensure an even oxide layer thickness of 40±5μm.



5. Sealing Treatment: Post-anodizing, high-temperature nickel sealing is applied to close the micro-pores of the oxide layer, significantly enhancing its corrosion and wear resistance, and eliminating surface adsorption.



6. Full Inspection & Shipping: 100% inspection for dimensions, hardness, layer thickness, and appearance.合格 products are packaged with custom protective sleeves to prevent shipping damage.

• Fully traceable process parameters, stable quality.
• Specializes in machining large aspect ratio thin-walled tubes prone to deformation.
• Uniform anodized layer thickness, no color difference.
• Strict outgoing inspection standards.

This processing technology is suitable for manufacturing all precision aluminum tubular components with high requirements for straightness, wear resistance, and dimensional accuracy.

Professional OEM processing services are available based on your supplied materials or drawings, offering one-stop production from raw material to surface treatment.

Provide quality data reports during processing. Process validation and optimization services can be offered based on customer needs.