What is a Cold Planer, and how does it work?

A cold planer is a piece of heavy machinery that is used to remove materials such as sidewalks and roads. Cold planers are most typically used by road construction teams and are suitable for both asphalt concrete and bituminous pavement. They may be retained by large construction organizations for special projects, and they are also sometimes available through equipment rental businesses. The price of a cold planer, whether new or secondhand, varies based on the type and functionality available.

The cold planer features a drill-like head that can be used to break up the material so it can be removed. The angle and depth of the cold planer can be changed to accurately cut down to the required depth. This enables crews to perform tasks such as removing the upper layers of a road while leaving the lower levels intact, allowing them to precisely control this stage of the project. Readers who have witnessed road crews remove a section of the road may have noticed that the underlying layers are frequently grooved when they are revealed. This is due to the drill head on the cold planer.

Source; wise-geek