Unplanned maintenance can result in loss of production, create higher costs for parts and increase service time. By assessing what equipment and tools they use on a daily basis, quarry operators can better predict their expenses and use that information when creating a planned maintenance (PM) contract.
“Like any piece of heavy equipment, proper and timely scheduled maintenance will extend the life of the equipment and save the owner money over time,” Bereika said. ?“A PM contract also means the owner can complete maintenance during off hours, rather than having to shut down the machine on the jobsite.”
Additionally, a planned maintenance contract can provide an operator with future hourly costs to better understand the machine’s current operating costs. By working with an equipment dealer on a PM contract, operators can better predict expenses, reduce downtime and extend machine life.
“Dealers know what parts should be stocked, not only by themselves, but by equipment owners,” Bereika said. “They ensure that scheduled maintenance is performed on time and at a convenient time to the equipment owner. All this helps control costs.”
Making a PM schedule easy to follow and documenting service intervals allows operators to easily ensure each item is completed weekly, monthly, quarterly or as scheduled. Bereika said operators could also assess parts, labour, travel, supplies, lubricants and GPS fleet tracking systems, such as telematics, to better budget for ongoing maintenance.
“Wear items should be in stock and common supplies should be on hand to help reduce downtime,” he said. “As far as lubricants go, owners should know the manufacturer’s requirements. Using the wrong lubricants can lead to expensive, unnecessary repairs.”
If operators experience mechanical issues, Bereika recommended completing a visual and on-board diagnostic check and then following up with their in house mechanics to better understand what repairs are needed prior to calling a service technician. Collecting as much information about the problem as possible before talking to the service department will greatly simplify the repair process and reduce downtime. However, Bereika added that working on major components on an ADT required specialised training, so in most cases a dealer service technician will be required.
A standard maintenance schedule is affixed to the ADT cab for easy reference and can be found in the operation and maintenance manual. Knowing the fixed costs of planned maintenance upfront can help operators minimise unexpected business expenses. Fixed costs also instill confidence if operators know how much the operating costs will be, and by incorporating planned maintenance, they can ensure the machine is serviced on time.
Minimising downtime
ADTs are designed to haul the most dirt, rock, stone and gravel with the lowest cost per tonne transported. These machines also excel in soft and slippery loading and dumping applications, and particularly in overburden removal, transport to crusher, crusher to stockpile and site reclamation applications compared with other heavy equipment. So if the machine is experiencing issues, the last thing you want to do is waste valuable time servicing it.
With a PM contract, servicing time is typically based on the manufacturers’ and equipment owners’ schedules. According to Bereika, a PM contract also ensures maintenance will be performed as required to help minimise any machine issues that can be caused because of lack of scheduled maintenance.
In addition to a PM contract, Bereika said ADT owners and operators should perform three other preventive maintenance procedures:
- Inspecting the auto-lubrication system, if installed, to ensure that there is no premature component failure due to lack of grease.
- Assessing tyre air pressure, wear and damage on a regular basis.
- Utilising diagnostic tools to monitor engine temperature and rpm history, for example, to prevent future engine damage and major premature repairs.
Bereika estimated that the auto-lubrication system greases the major components about every 30 to 45 minutes when the machine is in operation. Although the system saves valuable labour, it must be monitored to ensure that the grease reservoir is filled and there are no fault codes associated with the system.
Another preventative maintenance step is to visually and manually check tyres for wear and damage.
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“Low tyre pressure can cause sidewall failure and machine instability,” Bereika said. “A visual inspection will show if the tyre has tread punctures or sidewall damage because of road hazards. Also, look for rocks wedged in between dual tyres, which can cause tyre failure.”
Radial two-star E3 tyres come standard on many ADTs and will work in most mining applications. However, if the tyres are coming into contact with sharp objects such as shale, Bereika suggested using E4 tyres with their stronger sidewalls and deeper treads. A tyre specialist should be consulted for more information.
Diagnostic tools can be used as preventative maintenance procedures by analysing component historical data, especially in regard to the engine, transmission, electronics and the auto-lubrication system. Owners and operators should ask their dealership about purchasing diagnostic tools.
Bereika also said that operators should immediately repair components that are failing, rather than wait until later when components are more likely to fail.
“It is less costly repairing the component before failure because it can be done based off of the owner’s schedule rather than the equipment,” he said. “By doing this, it can also save owners a considerable amount of money and time in the long run due to the fact that pre-failure repair costs are less than total failure costs.”
Serviceability
ADTs work hard in all terrains, so scheduling proactive site maintenance intervals is crucial to extending machine life. If properly serviced, ADTs — even those used in extreme environments — can have a life expectancy of about 10 years (between 10,000 and 20,000 hours).
“What is really necessary is easy access to filters and other parts involved in PM,” Bereika said. “Labour is a major component of PM cost, and easy access to all areas of the engine compartment helps keep costs low.”
For instance, ADTs used in extremely hot or cold temperatures require more frequent maintenance schedules as well as alternative oils. Machines working in extremely dusty conditions may require multiple air filter replacements and daily cleaning. When used in muddy applications, ADTs may have to be greased more often because the driveshaft and other bearings come into constant contact with the mud. Failure to schedule maintenance can affect engine performance, reduce productivity and burn more fuel.
Using bio-fuels can also lead to fuel thickening and fuel filters clogging, requiring shorter service intervals. Bereika warned that if operators are using bio fuels, they should check with their engine manufacturer to learn about proper service intervals.
Operators should visit their dealers to create a unique package that can address their maintenance needs and assess key machine features — parts, labour, travel, supplies and lubricants — before servicing the machines.
“Your dealership should know you and how you utilise your machines,” Bereika said. “They can cater a maintenance schedule to fit your specific requirements.”
Additionally, by reviewing GPS fleet tracking systems, owners and dealers can see when an ADT needs to be serviced and can better budget for ongoing maintenance.
Resale value
The machine condition dramatically affects the resale price of the equipment. For instance, if there are visible signs the equipment hasn’t been properly maintained, has damage or major component wear, the resale value can be dramatically reduced.
“A low resale value can severely affect the machine’s cost of ownership, possibly making it questionable to own,” Bereika said. “The most important thing (when reselling) is that the major components, such as the engine, transmission and differentials, are in good working order. Proof of a PM contract is also valuable in maintaining resale value.”
{{image3-a:r-w:200}}To maximise resale value, Bereika suggested following these tips before creating a PM contract:
- Review the machine’s scheduled maintenance chart.
- Identify how you are going to use the equipment.
- Identify low utilisation times for maintenance.
- Identify the length of term you would like to establish preventative maintenance.
- Discuss the plan with your dealership.
- Create a PM contract.
After the truck’s operating hours reach a certain predictable level, many ADTs can be rebuilt for a so-called “second life”. Other times, ADTs are used as back-up units or converted into water trucks.
“All major components, such as the engine, transmission and differentials, have an expected life and have to be rebuilt periodically,” Bereika said. “If they are, the machine’s life can be extended at a cost lower than the replacement cost.” This time frame will vary greatly depending on whether the ADT has had light, medium or heavy-duty tasks.
By planning ahead for maintenance, quarry operators can help predict expenses, minimise downtime, easily service the machine and increase the resale value of the ADT.
Source: Clark Equipment/Doosan Infracore Construction Equipment America