Asphalt milling, also known as cold planing, is a process that removes part of a paved surface, such as a parking lot or road. Milling can remove just the surface of the pavement, or anywhere up to the entire depth, referred to as full depth removal. There are many reasons to mill a paved area, including leveling a paved surface or repairing damage that the pavement has incurred.
Milling is achieved using a heavy-duty piece of construction equipment known as a milling machine, or a cold planer. Milling machines utilize a large, rotating drum that removes and grinds the surface of the asphalt. Scrolls of tool holders cover the exterior of the drum and hold the carbide cutters that actually cut the pavement.
Water is generally applied to the drum while milling, which helps to reduce the extreme heat produced by the machine, as well as minimize any airborne dust caused by milling.