Kieswetter says Infrared Repair Corp., Kitchener, which subcontracted the preheating job from Miller Paving, preheated the base from 15 degrees F to between 68 and 86 degrees F. Miller Paving then placed the surface course asphalt. Infrared Repair Corp. also preheated the surface course to enable line striping to be done in such cold weather.
To preheat the surface Infrared Repair Corp. used a 16 foot x 8 foot Heat Design Equipment HDE 1600 that had been modified for cold weather paving (BTU input of 2.6 million BTU). The unit was placed in front of the paver and towed by a small truck.
"Ideally you want the preheating equipment to move as close as possible to the front of the paver so you don't lose a lot of heat," Kieswetter says.
Kieswetter says the pace of the preheating depends largely on the air temperature but more on the paving speed the contractor wants. He says most preheating work is done at the same rate as the paving, between 15 and 25 feet per minute.
"It also depends on the number of machines,"Kieswetter says."You can get by with one machine but if it's really cold or if the paving contractor wants to move a little faster you can heat with two machines so you can heat farther out."
He says that contractors should not be concerned about heating the pavement too long because the infrared unit keeps moving throughout the paving job.
"You're not heating the surface anywhere near the point where the pavement is workable, you're just preheating the pavement to 68 to 86 degrees F or so, so you don't have to worry about damaging the asphalt."
"Basically what you want to do is make sure the base asphalt is not acting as a heat sink, taking too much heat out of the surface course before you can get in compacted," Kieswetter says.
He says the project was a complete success.
"The surface course asphalt stayed bonded throughout the entire winter until the granular base failed in the spring thaw," he says.
Kieswetter says that using infrared to preheat pavement is "simple to do and easy to learn," and can be even easier and work even better when a material transfer vehicle is used in the paving trains.
"It just requires that the operator have proper preparation and training in propane gas safety," he says. "If he understands that it's pretty simple."
Kasi Infrared Pro Heat 2000
The Kasi Pro Heat 2000 infrared patching system includes a 48-square-foot Ultra glo pavement heater.
Indicate 101 on Inquiry Card
Asphalt Reheat Systems Split Box Infrared Heater
The Split Box infrared heater features chambers for 2x4, or 4x4 heat areas.
Indicate 102 on Inquiry Card
Keizer-Morris 4-48 Infrared Asphalt Recycler
The 4-48 infrared asphalt recycler from Keizer-Morris features a folding trailer design.
Indicate 103 on Inquiry Card
Ray-Tech Infrared Total Maintenance Vehicle
The Total Maintenance Vehicle is designed for making complete, permanent asphalt pavement repairs.
Indicate 104 on Inquiry Card
Marathon HEPR36 Infrared Heater
Marathon Equipment's HEPR36 infrared heater is available in walk-behind or trailer-mounted versions.
Indicate 105 on Inquiry Card
Heat DesignSkid-Steer Attachment
The Heat Design skid-steer attachment offers deck sizes of 8x4, 8x6, 8x8, 8x12, 8x16.