Precision CNC Machining Seamless Rectangular Tubes / Round Hole Steel Tubes

CNC precision machining of seamless square tubes/round hole steel tubes

Product Description

We specialize in high-precision CNC machining of seamless thick-walled steel tubes with outer square and inner round profiles, designed for structural, mechanical, and industrial applications. Our advanced machining capabilities ensure tight tolerances, superior surface finishes, and complex geometries for custom tube components.

Key Features & Benefits

✔ Premium Material Selection

• Carbon Steel (Q235, 20#, 45#)

• Alloy Steel (4140, 4340)

• Stainless Steel (304, 316)

• Aluminum & Other Metals (Upon Request)

✔ Precision CNC Machining Capabilities

• Tolerances: ±0.05mm (Standard) | ±0.02mm (High Precision)

• Wall Thickness: 3mm–50mm (Customizable)

• Outer Square Sizes: 20mm×20mm – 300mm×300mm

• Inner Round Bore: Ø10mm–Ø250mm

• Surface Finish: Ra 0.8–3.2μm (Grinding/Polishing Available)

✔ Machining Services

• Drilling & Boring – Precision hole machining for fittings and assemblies

• Milling & Grooving – Custom slots, keyways, and threads

• Cutting & Deburring – Smooth edges for safety and functionality

• End-Facing & Chamfering – Ready-to-install tube ends

✔ Customization & Rapid Prototyping

• Tailored Dimensions – Adjustable length, wall thickness, and bore size

• Secondary Processing – Heat treatment, galvanizing, powder coating

• Fast Turnaround – Prototypes in 5–7 days | Production in 10–20 days

✔ Quality Assurance

• 100% Dimensional Inspection (CMM, Laser Measurement)

• Material Certification (MTC, SGS, EN 10204-3.1)

• Non-Destructive Testing (UT, Eddy Current)

Product parameters :

1. Basic Parameters

2. Machining Capabilities

3. Performance & Testing

4. Customization & Logistics

Applications

• Construction & Architecture – Structural frames, railings, support columns

• Machinery & Automation – Hydraulic cylinders, linear guides, robotic arms

• Energy & Oil/Gas – Pipeline systems, pressure vessels

• Transportation – Chassis components, roll cages

Why Choose Us?

✅ Advanced CNC Equipment – Multi-axis machining centers & lathes
✅ Engineer Support – DFM optimization & CAD/CAM assistance
✅ Competitive Pricing – Cost-effective for both prototypes & bulk orders
✅ ISO 9001 Certified – Reliable quality control

Qingdao Sande Technology Co., Ltd. is located in Qingdao. We are specialized in manufacturing forging, CNC machining and various surface treatments. We have over 16 years of experience.
We have a professional and experienced team of engineers, advanced production and testing equipment, a powerful quality control system, and professional customer service... We will offer professional services, high-quality products and favorable prices. We sincerely welcome domestic and foreign customers to cooperate with us!