With an operating weight of 74,580 pounds (33,829 kg) and rated power of 630 hp (470 kW), the PM622 easily milled the 2½-inch (64 mm) concrete layer. “We can mill with such precision with this machine. It doesn’t chatter, the tracks don’t jump. It handles tough jobs like this better than any machine that we’ve seen,” Carpenter says.

The Tri-City Blacktop crew milled within 1/8-inch (3 mm) of the specified depth. “The city doesn’t want us to get into the rebar that’s in the concrete, so they didn’t want us going any deeper,” Carpenter says. “We didn’t hit any rebar. It’s been a very smooth job.”

Meeting the milling specifications was also critical to keeping the existing hand-framed curbs intact. The city didn’t want the road height changed, which would have required curb replacement. Tri-City Blacktop met the specs, and new curbs weren’t necessary.

Perfect Every Time

The PM622’s technology helped the crew complete milling quickly. “True zero for matching is stored in the grade control system. There’s never any second guessing. Once you get the machine set up, it’s always set up,” Carpenter says. “You can set down at two and a half inches and taper that out 30 feet to two inches and not have to do it manually. It will do a perfect taper every time.”

“TRUE ZERO FOR MATCHING IS STORED IN THE GRADE CONTROL SYSTEM. THERE’S NEVER ANY SECOND GUESSING. ONCE YOU GET THE MACHINE SET UP, IT’S ALWAYS SET UP.”

A highly skilled crew is necessary to mill at the rate that Tri-City Blacktop did on the Middle Road resurfacing project. “We’ve had this crew together for 20-plus years. They do a great job,” Carpenter says.

Sometimes you catch a break, too. Topography worked in favor of Tri-City Blacktop. “This job has some hills, and we’re using them to our advantage. Downhill, with the gravity, is helping us move a little quicker through the concrete,” Carpenter says.

Tri-City Blacktop successfully met a 0.25-inch (6 mm) over 10 feet (3 m) bump specification. The crew used a Cat AP655F Asphalt Paver to place three lifts: 1-inch (25 mm) sand level mix for crack fill, 2-inch (51 mm) intermediate lift, and a 1.25-inch (32 mm) surface lift. A total of approximately 6,000 tons (5443 metric tons) of material was placed. The asphalt was produced at a Tri-City Blacktop plant three miles from the jobsite.

The PM622’s controls are similar to those on Cat pavers. “We’re all familiar with the pavers. Caterpillar did a really good job tying the two together. You can jump from one to the other without having any doubt in what you’re doing. Grade control is laid out the same on both,” Carpenter says.

And when the Tri-City Blacktop crew was finished with the job, a rough section of Middle Road was smooth driving—on time and with all specifications met.

Support and Service Makes the Difference

When Larry Carpenter founded Tri-City Blacktop, Inc. in 1969, he used Cat machines. Two generations later, the company’s fleet has grown to more than 30 Cat machines, including loaders, a dozer, rollers, a motor grader, cold planer and a paver.

The company does new construction, overlays, and a variety of other types of asphalt work. “Basically, we do anything from the ground up, except for general contracting,” says Luke Carpenter, field superintendent. “Seventy percent of our work is milling and paving.”

The PM622 Cold Planer is the newest Cat machine owned by Tri-City Blacktop. “When they released this mill, there was no question that we were going to have one,” says Luke Carpenter, field superintendent.

The service points on the PM622 are quickly accessible. “Everything is easy to get to—the filters, the drains, everything,” Carpenter says. “The tool holder system is very easy to change, very fast. There’s no bolts to tighten. It’s a 30-second change.” 

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Dependability of Cat machines was also a significant factor. “Our uptime with Cat equipment is 98 percent. We’ve virtually eliminated downtime,” Carpenter says. “The way that jobs are figured now, you can’t afford downtime.”

And the machine is equipped with Product LinkTM, which provides a wealth of information about machine performance to identify and address any problems to prevent breakdowns and keep uptime high.

Support and service that Tri-City Blacktop, Inc. receives from both Caterpillar and Cat dealer, Altorfer, were key components in the decision to purchase the machine. “They’ve never let us down,” Carpenter says.

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