Machine drivetrain major component rebuild costs account for over 60% of total machine maintenance and repairs costs excluding tires and fuel. An effective condition monitoring plan for your components will reduce machine operating costs through improving major component life. This directly impacts machine cost per hour and the bottom line.
Improving major component life also has the additional benefit of reducing the frequency of planned and unplanned machine stoppages, which increases machine overall availability and production.
Managing major component life involves two basic fundamentals:
- Eliminate or reduce unplanned component removals due to failures or premature wear. Since failures often shorten life by 50% or more, taking action to reduce the frequency of failures has a significant impact on average fleet component life.
- Set, monitor, evaluate, and adjust planned component replacement (PCR) targets for optimum life.
1. Collect and analyze component life data and information.
Fleet component life hours achieved are tracked and summarized by machine model. Required data includes:
- Machine model
- Machine serial number
- Component name (such as engine, transmission, wheel group, differential, torque converter, suspension, etc.)
- Component serial number (or assigned ID number)
- Component removal date
- Hours on component when removed
- Removal planned or unplanned? (Failure or Planned Component Replacement)
- Root Cause of Failure (part / part group causing failure)
- Component source (component removed was new, reman, or rebuilt)
- Other helpful data as appropriate, such as “total engine fuel burn”
The component life data should be collected as a minimum for all component removals over the past three years. Over a three year period, close to 100% of the fleet components will have completed a life cycle. Component life data that is more than five years old should not be used in the analysis of “current” fleet component life performance.
2. Reducing Early Failures and Premature Wear Out
The management and reduction of early hour failures and premature wear out is a key success factor in increasing overall component life and machine reliability.
- Identify the root causes of failure impacting the machines.
- Determine and prioritize the top issues.
- Develop containment and solutions
It is important to the process to identify the “root cause” for any component removed prior to reaching the planned life target. A technical failure analysis is the best means to identify the root causes of failures.
A common mistake is to identify “what” failed rather than “why” it failed. Understanding true root causes enables preventative actions to be developed and implemented.
Failures usually originate from one or more of the following sources:
- Part defect (Caterpillar or Rebuilder Reuse and Salvage)
- Workmanship defect (Caterpillar or Rebuilder)
- Engineering Design (Caterpillar)
- Maintenance practices (Minesite)
- Operation practices (Minesite)
- Improper Removal and Installation – system contamination (Installer)
It is vital to establish a policy to perform technical failure analysis on all premature removals and a resource to provide the analysis. Most Caterpillar dealers have extensive Applied Failure Analysis (AFA) training, tooling and lab equipment required, as well as extensive knowledge of Caterpillar equipment, specifications, and technical product issues.
Define and Prioritize Issues
The accumulation of failure analysis information allows the top reasons for failures to be identified and prioritized by those issues which are most impacting component life and machine availability. Plans and actions can then be developed to contain known problems and find permanent solutions.
Action Plan – Containment and Solutions
Once key issues affecting component life performance and availability are identified and prioritized, action plans can be developed. Action plans consist of temporary containment measures and permanent corrective measures.
Temporary containment options may include:
- Identify which machines that may be affected by an issue
- Inspect machines for a defect
- Monitor machines for signs of a developing problem. VIMS data, oil analysis, particle count, magnetic plug and filter inspections, testing, etc.
- Perform a mid- life replacement of part or subcomponent known to be causing issues.
- Temporary machine systems modification
Permanent solutions may include:
- Updated part or design from Caterpillar/manufacturer
- Change in workmanship procedure
- Change in maintenance procedure
- Change in operation procedure
3. Manage and Adjust Planned Component Replacement Intervals
Determine Component Life Targets
- Cat / Dealer Recommendation
- Experience and History
- Experience in similar applications
- Load Factors – Fuel Burn Rate
Track Component PCR Life
- Average PCR Life
- Percentage of Components Reaching PCR
Adjusting PCR Targets
- Evaluate component condition during rebuild – life remaining?
- Rebuild based on condition rather than by hours alone
- Monitor oil consumption, smoke, oil analysis, particle count, VIMS, etc
- Evaluate parts reusability/rebuild costs at PCR
The fundamentals of this component life improvement process are:
- Collect and Analyze Component Life Data
- Manage Early Hour Failures and Premature Wear Out
- Manage and Adjust Planned Component Rebuild (PCR) Intervals
To implement, the requirements are:
- Company commitment to create an availability / component life management process
- Process owner: Assign a Reliability Manager / Engineer
- Administrative system and database to track component life
- Maintenance and Repair records database
- Policy on performing failure analysis and a database for reports and history tracking
- Develop desired management reports
- Use data to identify opportunities
- Explore opportunities for causes and solutions
- Implement containment and solutions
- Improved fleet availability and production
- Increased average fleet component life lowers cost per hour
- Reduced unplanned machine stoppages – improved scheduling and planning
- Lower parts consumption due to reduced failure rates
Cashman Equipment’s Product Support Sales and/or Technical Services Representatives can assist you with implementing this process for your job or mine site.