Life cycles: Concrete pavers
| June 12, 2007 |
Given the cost and complexity of setting up and transporting concrete pavers, most of these machines don’t log a lot of engine hours in the course of a year. As a result, contractors often keep their machines 10 and sometimes even 20 years before they sell them.
There are a few components that need replacement every year or two, but other than those and routine maintenance, concrete pavers don’t require substantial reinvestments to maintain productivity.
PATTERNS OF USE
There are many variables that affect the number of hours a concrete paver will run in the course of a year and these affect maintenance costs and considerations.
Climate plays a big role in hourly usage. According to Chapin Sipherd, product manager, pavers and trimmers at CMI, in the North and upper Midwest contractors will pave for 12 to 14 hours a day six days a week for five to six months out of a year. In the South and West, crews will work nine to 10 hours a day five days a week but go for 11 months out of the year. The cold-weather downtime northern contractors experience gives them the advantage of being able to do more preventive maintenance. In the warmer climates many contractors are often so busy they feel they can only fix something after it has broken. And given the shorter work season up North, many contracts are put on accelerated work schedules with penalties for delayed work. That makes it all the more important for northern contractors to avoid on-the-job-breakdowns.
The size of the machine also has an impact on hours. The biggest highway pavers can take days to transport and set up. Smaller, less cumbersome machines set up quicker and as a result spend more time laying down concrete.
So, on the low end, cold weather contractors with larger concrete pavers may only put 300 to 500 hours on each machine per year. Warm climate contractors with smaller machines could go 700 to 1,500 hours.
Given the relatively low-hour environment that concrete pavers enjoy it’s not uncommon for contractors to keep smaller machines for five to seven years and larger machines seven to 10 years. And with good maintenance and rebuilds, machines lasting 15 to 20 years are not uncommon.
DECIDING TO KEEP OR SELL
Increasing maintenance costs and downtime are the primary reasons contractors unload their old pavers. And older machines that are fully depreciated no longer bring the contractor any tax advantages, Sipherd says.
New technology can also be a huge inducement for contractors to trade up. “The electronics have improved dramatically in the past 10 years,” says Ron Guntert, president of Guntert & Zimmerman. “They’re easier to troubleshoot, very reliable and getting better all the time,” he says. With electronic controls, contractors have higher productivity and less downtime and the machine will hold line and grade better so there’s a better-finished product.
Larger contractors are more likely to reap the benefits of new electronics, says Fred Hite, managing director of Power Pavers. But smaller contractors may not have the shop personnel to adequately repair a highly sophisticated machine. For that reason, says Hite, his company offers both types of machines – those with advanced electronics and machines that are fully hydraulic.
The push for new digital technology on pavers is coming from operators. “Operators insisted on the new technology because it made operations simpler, setup became easier and the self-diagnostics were just a dream come true,” says Kevin Klein, research and development manager for GOMACO, which introduced a micro-controller in 1986.
And given the amount of time it takes to transport and set up a concrete paver, design changes that help speed up this process can affect a contractor’s total capital outlay. Guntert says machines with decreased setup time may allow a contractor to do the same amount of work with one instead of two or two instead of three machines.
Different requirements and specs on jobs may also motivate contractors to purchase a new machine, or add features to their existing machines, says Klein. “Project specifications could call for dowel bar insertion and contractors will purchase an In-The-Pan-Dowel Bar Inserter to help them save time and money. Other machine options could include keyway crimpers, front and/or side-mounted bar inserters, transition adjusters, pressure compensated sideplates and other features,” he says.
Government agencies are also tightening the specs on what they will allow for ridability, and meeting these specs in some cases may require a newer machine. “It takes a precision paving machine to meet some of the strict rideability specifications demanded today,” Klein says.
REBUILDS AND REPAIRS
Since most of the wear on a concrete machine happens on replaceable components most contractors will do this work themselves. CMI takes trade-ins and repairs components, says Sipherd, but doesn’t refurbish or remanufacture machines.
Guntert says his company does some refurbishing, but the decision to do so usually depends on the philosophy of the contractor. “Some don’t believe in overhauls; when they trade they want new,” he says.
At Power Pavers Hite says they will do overhauls for the original owners of the company’s pavers and these overhauls typically cost between 35 and 60 percent of the cost of new depending on the extent of the repairs.
GOMACO’s distributors take used machine trade-ins and an affiliate company, GEC, that specializes in pre-owned GOMACO equipment runs a refurbishing program with services that range from something as simple as steam cleaning to complete machine overhauls.
MAJOR COMPONENT COSTS
Augers: The life of the auger depends on the abrasiveness of the concrete, but in most cases you should plan to rebuild the individual flights every season or every 500 to 1,500 hours. Costs will run about $75 per foot of auger length for rebuilds and around $350 for complete replacment. Some OEMs will offer other material conveyance designs such as spreader plows, which eliminate this maintenance cost.
Vibrators: These typically last 800 to 1,500 hours between rebuilds, which average around $450. Toward the last half of the machine’s life you may need to buy new vibrators that will cost $1,200 to $1,500 each.
Some state and federal paving projects require documentation on vibration and rates of 5,000 to 8,000 vpm to get thorough material consolidation. To eliminate the need to manually test the vibrators, says Hite, a number of contractors are replacing their old vibrators with “smart vibrators” that use a sensor to supply data to a monitor at the operator’s control console. The monitor scans the output of each vibrator to ensure the vibrators are continuously operating at optimum performance while recording the data for later review.
Hydraulic pumps: Expect to rebuild hydraulic pumps every 2,000 hours or so at a cost of $500 to $750. Complete replacement occurs typically at the halfway point in a paver’s life (5,000 to 7,000 hours) and can run anywhere from $1,500 to $8,000 depending on the size of the pump.
The age of your machine may also have a bearing on the lifecycle of the pumps. Sipherd estimates the new model pumps may last up to 30 percent longer than those from a decade ago. “The pumps and motors are higher quality and greater capacity,” he says. “You can do more with one motor today than you used to be able to do with two. And they are more reliable.”
Gear boxes: Put all your gear boxes on a regular maintenance program that includes replacement of the bearings at 2,500 hours, and anticipate replacing the gearbox at 5,000 to 10,000 hours for a cost of $2,500 to $7,000, depending on its size.
Undercarriage: The slow and steady pace of paving translates into very little wear on the undercarriage. Most will last the life of the machine. Rubber track pads will need replacement at 3,000 to 5,000 hours at a cost of $40 to $50 per pad. Polyurethane pads will go 5,000 to 10,000 hours and replacements cost $60 to $70 per pad. Steel track pads will last the life of the undercarriage. At the end of a paver’s lifecycle a complete undercarriage rebuild will cost around $12,000 to $20,000.
Engines: Expect most diesel paver engines to last 10,000 to 15,000 hours or the life of the machine. A remanufactured replacement engine will typically cost about 60 percent of the cost of a new engine.