Custom Precision Machining of Long Rods and Shaft Components

Core strengths
Process Advantages

Equipment Capabilities

- CNC Lathes: 32 units (Max. processing diameter: φ500 mm; Max. length: 3000 mm)
- Machining Centers: 28 units (Capable of machining complex shaft-end flanges, flats, grooves, and drilled holes)
- Centerless Grinders: 8 units (Ensuring precise outer diameter accuracy and surface finish)
- Deep-Hole Drilling Machines: 5 units (Max. depth-to-diameter ratio: 30:1)
- Polishing Equipment: Automatic polishing machines, mirror polishing machines
- Inspection Equipment: Coordinate Measuring Machines (CMM), surface roughness testers, hardness testers, laser diameter gauges

Core Product Introduction

1. Precision Piston Rods

Product Function
The piston rod serves as the core transmission component in hydraulic and pneumatic cylinders, converting hydraulic or pneumatic energy into mechanical energy while withstanding the pressure, impact, and friction associated with reciprocating motion.

Technical Specifications
- Material Selection:
- 45Steel: Economical and general-purpose; quenched and tempered to a hardness of HB220–280.
- 40Cr: High strength; quenched and tempered followed by high-frequency induction hardening; surface hardness of HRC45–50.
- 304/316 Stainless Steel: Corrosion-resistant; suitable for food processing, medical, and marine environments.
- Chrome-Plated Rods: 45steel substrate with a hard chrome plating layer; surface hardness of HV700–1150.

Precision Grade:
- Outer Diameter Tolerance: f7–f8 (Standard), h6–h7 (Precision).
- Straightness: ≤0.05 mm/1000 mm.
- Surface Roughness: Ra 0.2–0.4 μm (after chrome plating and polishing).
- Chrome Plating Thickness: 0.015–0.025 mm.

Dimension Range:
- Diameter: φ10–φ200 mm.
- Length: 100–6000 mm.
- Standard Lengths: 1–6 meters.

Processing Features
- Quenching and Tempering: Achieves excellent overall mechanical properties.
- High-Frequency Induction Hardening: Surface hardening to enhance wear resistance.
- Hard Chrome Electroplating: Provides corrosion resistance, wear resistance, and a low coefficient of friction.
- Mirror Polishing: Achieves a mirror-finish effect (Ra 0.2 μm level), extending the service life of seals.

2. Precision Guide Shafts / Optical Shafts

Product Function
Guide shafts serve as the guiding elements within linear motion systems; when paired with linear bearings or sliding bearings, they enable precise linear guidance.

Technical Specifications
- Material Options:
- Bearing Steel (GCr15): High hardness, high wear resistance; quenched hardness HRC60–64.
- 45 Steel (Chrome-Plated): Economical and practical; wear-resistant surface.
- Stainless Steel: Corrosion-resistant; suitable for clean environments.

- Precision Grade:
- Outer Diameter Tolerance: g6 class (for use with linear bearings).
- Straightness: ≤0.03 mm/1000 mm (Precision Grade).
- Roundness: ≤0.005 mm.
- Surface Roughness: Ra 0.1–0.2 μm.

- Dimensional Range:
- Diameter: φ4 – φ80 mm.
- Length: 50 – 4000 mm.

Processing Features
- Centerless Grinding: Ensures consistent outer diameter and high straightness.
- End-Face Machining: Capable of machining threaded holes, center holes, and keyways.
- Induction Hardening: Surface hardened layer depth of 1–2 mm.
- Super-Finishing/Polishing: Achieves a mirror-like finish, reducing the friction coefficient.

3. Pins / Shafts

Product Function
Pins serve as critical components in mechanical connections, facilitating hinged joints, precise positioning, or the transmission of low-magnitude torque. They are widely utilized across various sectors, including construction machinery, automotive manufacturing, and agricultural equipment.

Technical Specifications
- Material Selection:
- 45Steel: General-purpose grade
- 40Cr: High-strength grade (Quenched and Tempered)
- 20CrMnTi: Carburized and Quenched (Hard surface, tough core)
- Stainless Steel 304/316: Corrosion-resistant grade

- Precision Grade:
- Outer Diameter Tolerance: f8–h9 (General), h7–h8 (Precision)
- Straightness: ≤0.05 mm / 500 mm
- Surface Roughness: Ra 0.8–1.6 μm (Standard), Ra 0.4 μm (Precision)

- Special Features / Configurations:
- Pin Ends: Machinable features include threads, cotter pin holes, circlip grooves, knurling, and straight splines.
- Pin Heads: Machinable head types include hexagonal, square, spherical, and conical heads.

Processing Capabilities
- Turning: Single-setup machining for outer diameters, end faces, and undercut grooves.
- Milling: Machining of flats, slots, and square profiles.
- Drilling: Creation of radial holes, axial holes, and cotter pin holes.
- Knurling: Straight-pattern or cross-pattern knurling to enhance grip (anti-slip) or facilitate interference fits.

4. Lead Screws / Screw Rods

Product Function
A lead screw is a transmission component that converts rotational motion into linear motion. Based on precision requirements, lead screws can be categorized into general-purpose transmission screws and precision ball screws.

Technical Specifications
- Material Selection:
- 45Steel: For general-purpose transmission screws
- 40Cr: Quenched and tempered + high-frequency induction hardened to enhance wear resistance
- 9Mn2V: Exhibits minimal deformation during quenching; suitable for precision lead screws

- Thread Types:
- Trapezoidal Thread (Tr): Standard transmission thread
- Rectangular Thread: For large-lead transmission applications
- Sawtooth Thread: For unidirectional heavy-load transmission

- Precision Grades:
- Lead Accuracy: ±0.05mm/300mm (Precision grades can reach C5–C7 levels)
- Outer Diameter Tolerance: h7–h9 grades
- Straightness: ≤0.05mm/1000mm

Processing Features
- Whirl Milling: Efficient processing of threads on long lead screws
- Thread Grinding: Precision finishing of lead screw threads
- Quenching and Tempering: Improves machinability and mechanical properties
- Medium-Frequency Induction Hardening: Enhances the surface hardness of the threads

5. Motor Shaft / Rotor Shaft

Product Function
The motor shaft serves as the core rotating component of a motor; it transmits torque and supports the rotor, requiring high-precision dynamic balancing and fitting accuracy.

Technical Specifications
- Material Selection:
- 45Steel: General-purpose motor shafts
- 40Cr: High-power motors
- Stainless Steel: Motors for special environments

- Precision Grade:
- Bearing Journal Tolerance: k6–m6 grade
- Coaxiality: ≤0.02 mm
- Runout: ≤0.01 mm
- Surface Roughness: Ra 0.4–0.8 μm

- Special Features:
- Keyways, splines, flats, threads
- Center holes, steps, circlip grooves

Performance Specifications and Accuracy Grades

Surface Treatment Options

Profiles + CNC vs. Traditional Processes: A Comparison

Material Selection Guide

Quality Control System

Inspection Equipment
- Coordinate Measuring Machine (CMM): 1 Unit (Accuracy: ±0.002 mm)
- Laser Diameter Gauge: Online, non-contact diameter measurement
- Roughness & Contour Profiler: Surface quality and contour inspection
- Hardness Tester: Rockwell, Vickers, and Brinell hardness testing
- Universal Testing Machine: Mechanical property testing
- Metallurgical Microscope: Material microstructure analysis
- Magnetic Particle / Ultrasonic Testing: Internal defect detection

Inspection Items
- Dimensional Inspection: Outer diameter, length, step dimensions, threads
- Geometric Tolerances: Straightness, roundness, cylindricity, concentricity
- Surface Quality: Roughness, scratches, dents, corrosion
- Hardness Testing: Surface hardness, core hardness
- Plating Inspection: Coating thickness, adhesion, porosity
- Material Composition: Spectroscopic analysis to verify material grade

Application Scenarios

Industrial Automation
- Piston Rods (Pneumatic/Hydraulic): Actuating components for automated equipment
- Linear Guide Shafts: Used in conjunction with linear bearings
- Ball Screws: Precision positioning mechanisms
- Conveyor Rollers/Shafts: Material handling systems

Construction Machinery
- Hydraulic Cylinder Piston Rods: Excavators, loaders, cranes
- Pins/Pivot Shafts: Connecting components for booms, dipper sticks, and linkages
- Track Roller Shafts: Undercarriage/travel mechanisms

Printing & Packaging Machinery
- Printing Cylinder Shafts: Core components of printing presses
- Paper Guide Rollers: Paper transport systems
- Die-cutting Roller Shafts: Packaging machinery

Textile Machinery
- Spindle Shafts: Spinning machines
- Yarn Guide Rollers: Weaving looms
- Winding Shafts: Chemical fiber machinery

Woodworking Machinery
- Planer Cutter Shafts: Planers
- Saw Shafts: Circular saws
- Feed Rollers: Automatic feeding systems

Technical Support and Services

Phase 1: Requirements Consultation (1–2 Days)
- Drawing Analysis (2D/3D)
- Material Selection Recommendations
- Process Evaluation and Quotation

Phase 2: Technical Solution (2–3 Days)
- Process Route Design
- Heat Treatment Plan Confirmation
- Surface Treatment Plan

Phase 3: Sample Production (5–7 Days)
- CNC Programming
- Sample Machining
- Full-Dimensional Inspection
- Sample Approval

Phase 4: Mass Production (As Scheduled)
- Raw Material Procurement
- Automated Production
- Process Control
- Full Inspection and Packaging

Phase 5: After-Sales Service
- Quality Tracking
- Technical Support
- Continuous Improvement

Frequently Asked Questions

**Q: What is the maximum length of the shaft that can be processed?**
A: Our standard equipment can process shafts up to 3000mm in length; for special requirements, lengths up to 6000mm can be accommodated through negotiation.

**Q: What is the highest achievable straightness?**
A: For standard products, it is 0.05mm/1000mm; for precision-grade products, it can reach 0.02mm/1000mm.

**Q: What is the Minimum Order Quantity (MOQ)?**
A: Samples can be ordered starting from 1 piece. For mass production, the MOQ depends on the specific specifications, typically ranging from 50 to 100 pieces.

**Q: What thickness can the chrome plating layer be?**
A: The standard thickness is 0.015–0.025mm; for special requirements, it can reach up to 0.05mm.

**Q: Can you process shafts with flanges or non-standard end shapes?**
A: Yes. Our machining centers are capable of processing complex features on shaft ends, including flanges, flats, grooves, drilled holes, and more.

**Q: What heat treatment services do you offer?**
A: We offer tempering and quenching, high-frequency induction hardening, carburizing and quenching, nitriding, through-hardening, and other treatments.

**Q: How do you ensure consistency across mass production batches?**
A: We utilize centerless grinding machines for mass production and employ SPC (Statistical Process Control) to monitor and ensure the consistency of critical dimensions.

Request a Quote & Samples

We offer complimentary technical consultation and sample services:

Information Required for a Quote:
1. Drawings or detailed specifications (diameter, length, tolerance requirements)
2. Material requirements
3. Heat treatment requirements
4. Surface treatment requirements
5. Quantity and delivery schedule requirements

Sample Requests:
- Samples are available for verification purposes for new orders
- Sample costs may be refunded upon placement of the bulk order
- Comprehensive inspection reports are provided

Why choose us

Professional Manufacturing Capabilities
- Fleet of 32 CNC Lathes + 28 Machining Centers
- 8 Centerless Grinders, ensuring batch consistency
- Dedicated Deep-Hole Drilling Machines (Max. Depth: 3000mm)
- Annual Production Capacity: 2 million precision long-shaft components

Technical Team Capabilities
- Over 15 years of experience in machining shaft-type components
- Proficient in the properties of various materials and heat treatment processes
- Capable of providing recommendations for optimizing shaft structural designs
- Rapid resolution of technical machining issues

Rapid Response Capabilities
- Sample Lead Time: 5–7 business days
- Bulk Orders: 10–20 days
- Urgent Orders: 48-hour expedited channel

Quality Assurance
- ISO 9001:2015 Quality Management System
- IATF 16949 Automotive Industry Certification (for select production lines)
- Critical Dimensions: CPK ≥ 1.33
- 100% Factory Inspection; Inspection Reports Provided