Cold Mill Planing, or Milling is a process in which existing asphalt is milled down to a desired depth before resurfacing. This is a relatively new procedure and is part of the “green” technology in that it generates usable road base as a byproduct. This bypasses the normal crushing process necessary to produce standard road base.
Before OVERLAYS
Generally, the existing asphalt surface is milled prior to an overlay because there is no more room for additional height in the lot because of drainage concerns or trip hazards. The lot can either be edge milled or completely milled depending upon the properties’ individual circumstances.
R&R
Milling offers a huge savings advantage when it is used to completely remove an existing asphalt lot to the sub grade. Milled asphalt is accepted at many more sites than broken asphalt and is used for road base by all the Cities, Counties and CDOT. Unless it is contaminated by dirt or petromat, any asphalt plant will accept it for no dump charge. So if the customer doesn’t need the millings for a temporary surface or base reconstruction, there is no dump charge. That alone is a huge savings advantage.
The second, large advantage of full-depth milling is that it minimizes the “Wicking Effect”. When you full-dept mill asphalt, it is removed and graded in one pass. If there is moisture under the grounds surface, too much traveling over that surface by heavy equipment can “wick” the moisture to the surface. This can cause hard base to turn soft, resulting in the customer having to pay a change order to reconstruct the sub grade. The less travel over the dirt, the less possibility of the “wicking effect”.
Finally, there is a time savings by using the mill over conventional removal methods. The mill can cut prep time by between 20%- 40%. All of the above adds up to a huge customer savings when your paving contractor owns the mill.
In 2011, Perfect Patch Asphalt took possession of the first Wirtgen W-200 Cold Mill Planing machine to be sold in the State of Colorado. This State-of -The –Art, Highway Class milling machine offers the latest technology and can grade to within 1/10th of 1%. We invested in this machine in order to save our customers more money. If your paving contractor does not own their own mill, they cannot offer you this savings.
