How Do Chinese Manufacturers Like WALKSON Achieve High Precision in Forging 580mm Screw Rotors?

In the high-stakes world of industrial compressors and Roots blowers, a screw rotor isn't just a component — it's the heart of the machine. When that rotor reaches 580mm in diameter, the demands skyrocket: extreme pressure resistance, perfect helical profile accuracy, zero internal defects, and fatigue life measured in decades. Very few manufacturers on the planet can reliably deliver forged screw rotors at this size with tolerances that often hit ±0.05 mm on critical profiles. WALKSON, a leading Chinese precision forging specialist, consistently achieves these results — and does it at scale. Here's exactly how they do it.

Alloy steel 580mm screw rotors forged and finished at WALKSON

The Real Challenge: Size Meets ComplexityA 580mm screw rotor can weigh well over 2 tons in its forged blank state. The helical geometry must be precise enough to maintain micron-level clearances with its mating rotor, yet the part must withstand pressures exceeding 40 bar and continuous operation at 3,000–6,000 rpm. Casting simply cannot deliver the grain flow or mechanical properties needed. Only forging — specifically controlled open-die forging combined with precision closed-die finishing stages — can produce the required strength and reliability. This is where Chinese leaders like WALKSON have pulled far ahead of the pack.State-of-the-Art Equipment That Makes the Difference WALKSON operates some of the largest and most advanced hydraulic forging presses in China, with capabilities exceeding 8,000 tons of force. These are not ordinary presses — they feature:

• Real-time force and position feedback control accurate to millimeters

• Multi-direction forging manipulators that ensure uniform deformation even on asymmetrical      helical preforms

• Integrated induction heating systems maintain temperature windows within ±10 °C for      optimal material flow

This level of control eliminates the internal cracks and folds that plague lesser manufacturers when forging large-diameter helical components.The Precision Forging Process Step by Step

1. Material Selection & Billet Preparation
        Premium alloy steels (34CrNiMo6, 42CrMo4, 18CrNiMo7-6) are selected and rigorously tested. Every heat is accompanied by full chemical analysis and ultrasonic testing before forging even begins.
        → Learn more about optimal materials for large-diameter screw rotors

2. Precision Heating & Temperature Control
        Computer-controlled induction heating ensures uniform temperature distribution, preventing grain growth or decarburization that would compromise final properties.

3. Multi-Stage Open-Die Forging
        The billet is progressively shaped through calculated blows and rotations. WALKSON uses DEFORM-3D simulation software to predict material flow and prevent defects before metal ever touches the die — a critical advantage for 580mm+ diameters.
        → See the full process details here: Key Manufacturing Process for Large-Diameter Forged Screw Rotors

Open-die vs closed-die forging – WALKSON combines both techniques for maximum precision on complex helical components

1. Precision Closed-Die Finishing (when required)
        For the most demanding profiles, final shaping occurs in precision dies that achieve near-net-shape results, dramatically reducing machining allowance and preserving forged grain flow.

2. Advanced Heat Treatment
        Quenching and tempering in computer-controlled furnaces deliver hardness      uniformity within ±2 HRC across the entire 580mm cross-section — something virtually impossible with casting.

3. CNC Precision Machining & Profile Grinding
        5-axis CNC mills and dedicated rotor grinding machines produce the final helical profile with surface finishes better than Ra 0.8 and profile tolerances that consistently beat OEM specifications.

4. Non-Destructive Testing & Dimensional Verification
        Every rotor undergoes:

• 100 % ultrasonic testing

• Magnetic particle inspection

• 3D CMM measurement with full profile scanning

• Phase analysis and mechanical property testing from multiple locations

→ Read how WALKSON guarantees dimensional accuracy: Ensuring Dimensional Accuracy in Large Forged Screw Rotors

Why Leading Global Compressor Brands Trust WALKSON

• Proven compatibility with Atlas Copco, Aerzen, Kaeser, GHH Rand, and other major brands

• Superior fatigue life — forged rotors regularly achieve 3–5× longer service life than cast alternatives

• Full material traceability and EN 10204 3.2 certification as standard

• Competitive lead times (12–20 weeks for 580mm class rotors)

When performance cannot be compromised, industry leaders don’t gamble on cast rotors. They specify forged — and increasingly, they specify WALKSON.Ready to upgrade your compressor or Roots blower performance with genuine high-precision forged screw rotors?Explore WALKSON’s screw rotor capabilities → Contact our engineering team today or download our technical brochure for 580mm-class forged rotors.

Your next breakthrough in efficiency and reliability could be one conversation away.