In order to be effective, PM practices must be developed for each machine model and each machine application. Using one set standard across machine models and applications may result in over-servicing or under-servicing a machine, both of which may be detrimental to the machine and the associated cost of maintaining the machine.
As a starting point, managers should look to the equipment manufacturer’s guidelines. Most major manufacturers have developed and documented inspection programs for various intervals on their machines.
The inspections are based on average machine applications, assume proper operation and that machines are using all fluid, oils and filters that meet or exceed the manufacturer's recommendations.
After looking at individual manufacturer guidelines, the next step is to look at hour intervals. These are generally established as eight hours per day, five days per week and 176 hours per month, and generally repeat every 2,000 hours.
The manufacturer’s criteria must be considered as a starting point and modified to fit each individual’s application and circumstances to be effective.
The intervals that are selected and established for each individual’s operations must be designed to the company’s machines, specifications, policies and a host of other variables. To give an idea of how this can break out, the following is an example of a solid PM program.
8 to 10 Hours (Daily)
Approximately every day, a thorough inspection should be conducted by the equipment operator. This should include a walk-around examination of the machine, cleaning the cab glass and mirrors, daily lubrication of selected pivot points, checking of fluids and oils, brakes, tires and tire pressure, all safety systems incorporated into the machine and all operating controls and instruments.
Finally, and equally important, a written report identifying any deficiencies should be completed and submitted to the manager in charge of the PM program.
100 to 125 Hours (Bi-Weekly)
In addition to the daily process, the bi-weekly examination involves a machine cleaning cycle. When the equipment is clean, it should be inspected for any signs of leakage including oil, hydraulic fluid, fuel and coolant.
Necessary adjustments, such as belts and tensions and servicing the applicable systems, should be taken care of by a maintenance person who has reviewed the weekly operator's inspections reports.
200 to 250 Hours (Monthly)
Depending on usage, most companies use the monthly inspection process for the engine oil change and oil sample analysis.
Additionally, the machine should be inspected for signs of leakage, and for any hoses that appear worn or damaged.
The 500-hour maintenance generally includes the items included in the daily, bi-weekly and monthly maintenance and repairs, as well as fuel filter changes.
The 1,000-hour mark includes the items in the daily, bi-weekly and monthly inspections, and the changing of additional fluids and filters. An oil sampling should be conducted and the oil checked for contaminates. In addition, a fuel analysis should be performed.
It’s also at this time that predictive maintenance is most crucial, and a very detailed inspection must be performed to identify any developing problems that can be rectified at an early stage or planned for a scheduled repair, prior to failure. This inspection consists of several items, including checking gears by shifting at all gears, primary and secondary steering, clutch disconnect and heater and air conditioner function.
Looking for signs of leakage is also important.
2,000 to 5,000 Hours (Annual)
The 2,000- through the 5,000-hour interval, or the annual machine inspection is a very complete inspection that includes elements of all previously mentioned intervals such as oil changes, filter changes, coolant changes and oil sampling of all compartments of the machine. It also includes the predictive approach and elements from the 1,000-hour mark.
What’s more, it’s generally recommended that all pressures be checked, recorded and adjusted as necessary to the original machine’s specifications.
Stan Orr, CAE (Certified Association Executive), is president and chief staff officer (CSO) of Association of Equipment Management Professionals (AEMP) - the premier organization serving those who manage and maintain heavy equipment. www.aemp.org.