Failure Root Cause Engineering: A Systematic Analysis Framework for the Causes of Disc Spring and Wave Spring Failure

The failure of disc springs and wave springs goes beyond surface-level issues, often revealing systemic flaws in design, manufacturing, installation, or usage. Drawing on extensive failure case studies, Jiangsu Sunzo Industry Engineering provides a comprehensive causal analysis framework that traces problems from surface manifestations to root causes. This enables precise identification of core issues and implementation of effective corrective and preventive measures.

1、Hierarchical Analysis of Disc Spring Failure Mechanism

1. Materials and Microstructure Level

Fatigue failure mechanism:

High-cycle fatigue: Stress level below yield limit, number of cycles>10^5, crack initiation from surface defects or stress concentration

Low-cycle fatigue: Local stress exceeds the yield limit, with a cycle count <10⁴, accompanied by significant plastic deformation accumulation

 

Material performance degradation:

stress relaxation: the elastic modulus decreases under long-term static loading, and the loss rate of pre-tightening force exceeds the design allowable value

CREEP EFFECT: TIME-DEPENDENT DEFORMATION IN HIGH TEMPERATURE ENVIRONMENT

2. Design and calculation level

Load Spectrum Mismatch: Actual Operating Load Exceeds Statistical Envelope of Design Load Spectrum

Stress concentration coefficient underestimated: Stress concentration of local geometry such as fillet and groove is underestimated by more than 20%

Resonance risk neglect: The operating frequency coincides with or approaches the natural frequency of the spring

3. manufacturing process defect

Heat treatment anomaly:

Incomplete martensite transformation due to quenching temperature deviation

Insufficient tempering produces excessive residual stress

The depth of the surface decarburization layer exceeds 1% of its thickness.

 

forming defect ：

Stamping burrs not completely removed

excessive taper

The thickness uniformity does not meet the tolerance requirements of the national standard

4. Installation and Usage Issues

Installation deviation: the coaxiality deviation exceeds 0.5% of the installation hole diameter

Lubrication failure: improper lubricant selection or excessively long lubrication interval

Environmental Corrosion: Risk of Stress Corrosion Cracking Caused by Media Corrosion Is Not Considered

2、Special Mechanism of Wave Spring Failure

1. Fatigue characteristics in vibration environment

Micro-wear-induced fatigue: Oxidation wear particles generated by the micro-motion relative motion between the wave peak and the installation groove

Multi-axis stress state: bending, shear and contact stress at the peak

Frequency Resonance Effect: Resonant Standing Wave Formation of Waveform Structure at Specific Frequency

2. pre-tension matching problem

Over-tightening damage: The elastic force exceeds the required value of the bearing by more than 30%, resulting in peak plastic deformation.

Insufficient preload: fails to effectively eliminate axial clearance, resulting in impact loads

Pre-tension force decay: The pre-tension force decreases by more than 20% of the initial value after long-term use.

3. structural adaptability defect

The wave height to wave spacing ratio is beyond the optimal range.

End structure defect: excessive stress concentration coefficient in the transition zone of the end ring

Interference of Multi-layer Wave Spring: Additional Friction and Stress Caused by Interlayer Contact

3、systematic root cause tracing method

1. failure analysis process

Data acquisition: load spectrum, temperature, vibration spectrum

Macroscopic inspection: fracture morphology, wear pattern, and corrosion characteristics

Microanalysis: Metallographic Structure and Crack Propagation Path

Simulation Verification: Verification of Stress Distribution by Finite Element Analysis

2. responsibility matrix analysis

Design responsibility: Error in stress calculation, improper material selection

Manufacturing Responsibility: Process Control Failure, Inspection Omission

Responsibility for: Overloading, lack of maintenance

Environmental responsibility: Unforeseen change of working condition

4、Three Groups Elastic Failure Analysis Service System

We provide professional failure analysis solutions:

1. Technical Diagnostic Service

On-site Investigation: Engineer Collects First-hand Data

Laboratory Analysis: Comprehensive Material and Mechanical Testing Capabilities

Simulation Calculation:Stress Analysis Based on Actual Working Condition

2. Formulate improvement plan

Design optimization suggestion: Design modification based on analysis results

Process Improvement Plan: Targeted Improvement of Manufacturing Process

Follow the guidelines: Develop operational and maintenance specifications

3. prevention system construction

Failure Case Database: Establishing an Industry Failure Case Database

Early-warning Index System:Establishing the Monitoring Standard of Key Parameters

Regular Review Mechanism: Establishing a Regular Review System for Design and Use

5、engineering practice suggestion

Technical improvement based on analysis results:

1. Design improvement

Consider the load dispersion by using probabilistic design method

Introduce the design concept of damage tolerance

implement reliability growth plan

2. manufacturing process control

Establish key characteristic control plan

Implementation of Statistical Process Control (SPC)

Improve the traceability system

3. Use maintenance optimization

Develop a preventive maintenance plan

Establish a health monitoring system

Personnel training and certification

Accurate root cause analysis is the starting point of quality improvement, while systematic preventive measures serve as the safeguard for quality enhancement. Let us employ professional failure analysis techniques to ensure the reliability of your products.