The asphalt street in front of my house was recently resurfaced, and I watched the first step that stripped off the old asphalt by a giant machine with a conveyer belt that recycled the old asphalt onto a truck moving slowly in front. A week later, driving down to Pensacola through Knoxville and Chattanooga, I saw the same machines many times on road projects. They are surprisingly common. But what are they called? Who makes them? Where could I buy one if I wanted my own?
After some digging, I learned they are often called “millers,” and the process is called “milling the road,” but there is no consensus on this. Wikipedia describes the machine under “cold planer (also known as a pavement planer, pavement recycler, asphalt milling machine or roto-mill.)” They are ugly, noisy machines that have never earned an endearing name.
The machines were developed about 30 years ago, they say, not for recycling, but to restore the profile of the roads which were growing higher and higher crowns with each added layer. Drivers were sliding to the passenger’s side as their cars tilted at an angle approaching 30 degrees. An asphalt surface is only expected to have a lifetime of 8–12 years, so new layers build up quickly.
The machines, whatever you want to call them now, were once called “Galions” after their original manufacturer, the Galion Iron Works. Like farm harvesters and Zambonies, they combine several functions in one machine. A revolving drum with replaceable carbide spikes tears up the road surface, and the pieces are directed to the conveyer belt that loads them onto the truck. They move slowly on four small caterpillar tracks instead of wheels. Two people usually operate it, a driver high on top and another walking alongside to control the depth and to watch for manhole covers, dogs, and anything else not asphalt. The driver’s view is pretty much limited to watching the truck bed fill up. The driver on the one doing my street was rarely seated as he ran from side to side, trying to see what was happening. He was clearly the boss of the whole crew.
There are companies that manufacture and sell them, but I could not find a price. I guess when you buy something that big, you negotiate the cost to have one made.
The street on the next block down from my house has yet to be done. Whenever they start, I will be there, observing and asking questions.