Super Smooth ID Tubes (SSID) – ST52 Steel, H9 Tolerance, Ra0.4 – Ra0.8, Ø60.3 – 114.3 mm

Our Super Smooth ID Tubes (SSID) are engineered for applications requiring extremely 

Manufactured from high-strength ST52 steel, these tubes offer:

·Tight H9 tolerances for accurate fits
·Ultra-smooth inner surfaces (Ra0.4 – Ra0.8) for minimal friction
·Excellent straightness and roundness for hydraulic and precision applications

Ideal for hydraulic cylinders, pneumatic actuators, precision machinery, and tooling systems.

Key Features

·Material: ST52 steel
·Inner diameter finish: Ra0.4 – Ra0.8
·Dimensional accuracy: H9 tolerance
·Excellent straightness and roundness
·Available OD range: 60.3 – 114.3 mm
·Wall thickness: 4.75 – 6.35 mm
·Suitable for high-precision hydraulic and pneumatic systems

 Technical Specifications Table

(Custom sizes available on request)

Super Smooth ID Tubes – Surface Finish Comparison

Notes:

·Ra0.4 = ultra-smooth, minimal friction
·Ra0.6 = standard high-performance
·Ra0.8 = general-purpose hydraulic/pneumatic applications

Manufacturing Process

1. Selection of high-strength ST52 steel
2. Cold drawing or cold rolling to achieve OD and wall thickness
3. Precision honing for super smooth ID (Ra0.4 – Ra0.8)
4. Heat treatment for stress relief and optimized mechanical properties
5. Surface finishing – oiled, phosphated, or optional coatings
6. Inspection – dimensional checks, straightness, roundness, Ra measurement
7. How to Choose Super Smooth ID Tubes

Surface Finish (Ra)

·Ra0.4: Ultra-high precision (hydraulic, tooling, aerospace)
·Ra0.6: Standard high-performance (industrial machinery, automotive)
·Ra0.8: General-purpose hydraulic/pneumatic systems

Tolerance (H9 or H8)

·H9: Common for most SSID tubes
·H8: High precision for critical applications

Material (Steel Grade)

·ST52: High-strength steel for hydraulic and precision machinery
·Optional alloys for higher pressure or temperature

Size (OD x ID x Wall)

·Match cylinder or piston specifications
·Custom sizes available if standard sizes do not fit

Applications

·Hydraulic cylinders & pistons
·Pneumatic actuators
·Precision machinery & tooling
·Automotive and industrial equipment

Tips:

·Ra0.4–0.6 for high-speed or high-precision applications
·H9 tolerance ensures reliable sealing
·Verify wall thickness for hydraulic pressure rating
·Consider surface treatments for corrosion or lubrication