Forged Shaft Engineering Case 

Project Background

A large construction machinery manufacturer faced high equipment failure rates and rising maintenance costs. Analysis revealed that the primary issue was the use of welded shafts, which could not withstand heavy loads and impacts, leading to frequent replacements. To address this problem, the company decided to adopt forged shafts.

Project Overview

The objective of this project was to provide a series of high-performance forged shafts, including drive shafts and transmission shafts, for use in excavators and bulldozers.

Requirements Analysis

The customer specified the following requirements for the forged shafts:

1. Load Capacity: Capable of withstanding a static load of at least 150 kN.

2. Fatigue Life: Expected service life of over 10,000 hours.

3. Delivery Time: Production and delivery within 4 weeks.

Solution

1. Material Selection:

• High-strength alloy steel (e.g., 42CrMo) with a tensile strength of 800 MPa and a yield strength of 600 MPa.

2. Forging Process:

• Utilized hot forging to ensure a dense internal structure, minimizing defects and enhancing strength.

3. Machining Precision:

• Employed high-precision CNC machining, achieving a diameter tolerance of ±0.02 mm.

4. Quality Control:

• Implemented ultrasonic testing for each batch to ensure no internal defects.

Project Implementation

The project was executed in several phases:

1. Design Phase:

• Collaborated with the customer to design the shafts and perform mechanical analysis. Simulation results indicated the forged shafts could withstand loads significantly above 150 kN.

2. Production Phase:

• The production cycle for the forged shafts was 3 weeks, meeting the customer’s 4-week delivery requirement.

3. Testing Phase:

• Conducted fatigue testing on the forged shafts, which showed a fatigue life exceeding 12,000 hours under a 150 kN load.

Project Results

The successful implementation of the project yielded the following outcomes:

1. Performance Improvement:

• The new forged shafts maintained load capacities above 150 kN without any failures during operation.

2. Reduced Maintenance Costs:

• Compared to welded shafts, the forged shafts reduced failure rates by 40%, leading to a 30% decrease in maintenance costs.

3. Customer Satisfaction:

• Customer feedback highlighted the superior performance and extended service life of the new shafts, resulting in a long-term partnership.

Conclusion

This case study demonstrates the advantages of forged shafts in high-load applications. Through careful material selection and advanced manufacturing processes, we successfully met the customer’s needs while significantly enhancing equipment efficiency and reliability. We look forward to collaborating with more companies to promote high-performance forged shaft products.