BUCKET AS-MATERIAL HANDLING 4343348 - Caterpillar

Illustration 1 g00745964
(Y) Cost
(X) Time
(1) Cost of maintenance and repair that is planned
(2) Cost of maintenance and repair that is not planned In Illustration 1, line (1) represents the maintenance and repair costs for an owner that followed the recommendations for inspection, maintenance, and repair. The peaks represent overhauls.Line (2) represents the maintenance and repair costs for an owner that chose to operate beyond the recommended intervals. The initial cost of the “repair-after-failure” philosophy is lower. Also, the first overhaul was delayed. However, the peaks are higher than the peaks for the customer that used the “repair-before-failure” philosophy .The higher peaks result from two key factors:
Delaying an overhaul until a breakdown increases the chance of a catastrophic failure. This type of failure requires more parts, labor, and cleanup.
Excessive wear means that fewer components will be reusable. More labor may be required for salvage or repair of the components.When all of the costs are considered, “repair-before-failure” is the least expensive alternative for most components and engines.Waiting until the engine exhibits symptoms of excessive wear or failure is not practical. A planned overhaul before failure may be the best value for the following reasons:
Costly unplanned downtime can be avoided.
Many original parts can be reused according to the guidelines for reusable parts.
The service life of the engine can be extended without the risk of a major catastrophe due to engine failure.
Achieve the best cost/value relationship per hour of extended service life.Overhaul Intervals
Some factors that are important for determining the overhaul intervals include the following considerations:
Performance of preventive maintenance
Use of recommended lubricants
Use of recommended coolants
Use of recommended fuels
Proper installation
Operating conditions such as: high ambient temperatures, high altitude operation, tunnel operation and cold-weather operation.
Operation within acceptable limits
Engine load
Engine speedGenerally, engines that are operated at a reduced load and/or speed achieve more service life before an overhaul. However, this service life is for engines that are properly operated and maintained.Other factors must also be considered for determining a major overhaul:
The total amount of fuel consumption
The service hours of the engine
An increase of oil consumption
An increase of crankcase blowby
The wear metal analysis of the lube oil
An increase in the levels of noise and vibrationAn increase of wear metals in the lube oil indicates that the bearings and the surfaces that wear may require servicing. An increase in the levels of noise and vibration indicates that rotating parts require service.Note: Oil analysis can indicate a decrease of wear metals in the lube oil. The cylinder liners may be worn so that polishing of the bore occurs. Also, the increased use of lube oil will dilute the wear metals.Monitor the engine as the engine accumulates service hours. Consult your Cat dealer about scheduling a major overhaul.Note: The driven equipment may also require service when the engine is overhauled. Refer to the literature that is provided by the OEM of the driven equipment.Using Fuel Consumption For Calculating the Overhaul Intervals
Table 1
Equation For Calculating Overhaul Intervals
F/R = H
“F” is the estimated total amount of fuel consumption of the engine.
“R” is