Case Study: Precision CNC Turning and Welding for Complex Steel Bearings

Introduction

Steel bearings are critical components that can endure extreme loads and harsh environments. But traditional CNC turning is not an ideal processing choice when machining bearings with intricate internal geometries. This case study demonstrates how the Beska team combined CNC turning and precision welding to deliver a high-performance steel bearing. Let’s explore the details!

Client: A global mining equipment supplier required 150 pieces of custom bearings.

Demands:

Design Complexity: Internal asymmetrical oil channels and external flanges.
Material: GCr15 high-carbon chromium steel.
Precision: Post-welding concentricity ≤ ±0.03 mm.

Challenges: We could not machine deep internal oil channels with CNC turning simply. Welding GCr15 steel would lead to distortion and weakened heat-affected zones.

The Solution: A Synergy of CNC Turning and Welding

Step 1: Processing separate CNC Turning Components: Base Ring: We use a Mazak CNC lathe machined to ±0.01 mm tolerance. Oil Channel Section: Separately turned with micro-grooves. Material Optimization: Selected GCr15 to balance hardness and weldability.

Step 2: TIG Welding Process: We applied TIG welding with argon shielding. Jig-assisted alignment to ensure < 0.02 mm positional accuracy. Heat Control: Pulsed welding minimized HAZ and retained base material hardness.

Step 3: Post-Welding Refinement: Post-welding annealing at 600°C for 2 hours. Final CNC Finishing: Secondary turning removed residual distortion and achieved concentricity of ±0.025 mm.

Technical Validation

Parameter	Method	Result	Standard
Dimensional Accuracy	CMM (Hexagon Global S)	±0.025 mm	ISO 12180
Weld Integrity	X-ray inspection	Zero porosity/cracks	AWS D1.1
Fatigue Strength	Rotary bending test (10⁶ cycles)	520 MPa	ASTM E466

Client Testimonial

Zero Defects: All 150 pieces of bearings passed quality checks, avoiding extra reworking costs. Operational Efficiency: In general, it reduced machining time by 35% compared to traditional machining methods.

Client Testimonial: “The combination of CNC precision and welding expertise solved a design limitation. These bearings have performed greatly in our crushers for a long time.”

– Mining Equipment OEM’s Chief Engineer

Steel Selection & Post-Processing Insights

Grade	Key Properties	Best For	Process	Purpose	Typical Results
GCr15	High hardness, cost-effective	General industrial bearings	Quenching & Tempering	Enhances hardness and wear resistance	HRC 58–62, retained toughness
G20CrNiMo	Superior impact resistance (HRC 60–64)	Heavy-load mining bearings	Shot Peening	Improves fatigue life	30% longer lifespan
9Cr18Mo	Corrosion resistance (HV 600)	Marine/medical bearings	Nitriding	Boosts surface hardness/corrosion resistance	HV 1000+, 50 µm layer

What Can Beska Do For You?

At Beska, we turn manufacturing problems into opportunities. By integrating CNC turning with TIG welding techniques, we delivered a great bearing solution.
Contact us to explore how our CNC and welding expertise can solve your most complex challenges.

Get A Quote