company news about How Asphalt Pavers, Milling Machines, and Rollers Work Together

Building a road is a team effort, and three pieces of equipment are at the heart of the process: asphalt pavers, milling machines, and rollers. Each plays a unique role, and their coordination is key to creating a smooth, durable pavement. Let’s explore how these machines work together to build the roads we drive on.

The Role of Each Machine

· Milling Machine: Removes old asphalt, preparing the base course.

· Paver: Lays down new HMA evenly on the base.

· Roller: Compacts HMA to increase density and durability.

Step 1: Milling – Preparing the Base
The process starts with the milling machine. If the existing road has cracks or potholes, the machine grinds away the top layer (1–10 cm). This creates a smooth base for the new pavement and eliminates “reflective cracks” (cracks in old pavement that spread to new surfaces). Milled asphalt is often recycled into new HMA, reducing waste and cost.

Step 2: Paving – Laying Down New Asphalt
Once the base is prepared, the paver moves in. Dump trucks deliver hot HMA to the paver’s hopper. Conveyors move the material to the rear, where augers spread it evenly across the road width. The screed compacts the HMA to the desired thickness (4–10 cm) and creates a smooth surface. Modern pavers use automatic leveling systems to maintain consistency, even on uneven bases.

Step 3: Rolling – Compacting the Asphalt
The final step is rolling, done immediately after paving (while HMA is still hot). Rollers use static, vibratory, or kneading compaction to reduce air voids to <5%. The process involves three stages:

· Initial: Double drum roller (vibration off) compacts HMA into a stable shape.

· Intermediate: Pneumatic tire or vibrating roller achieves most of the compaction.

· Final: Double drum roller (vibration off) eliminates wheel tracks.

Why Coordination Matters

· Timing: The paver must lay HMA quickly so the roller can compact it before it cools (below 80°C, HMA becomes too stiff to compact).

· Quality Control: A smooth base (from milling) ensures the paver lays even HMA, which the roller can compact effectively.

· Efficiency: Coordination reduces downtime—e.g., dump trucks must deliver HMA at a steady rate so the paver doesn’t stop (causing uneven surfaces).

Real-World Example
In a highway project, the milling machine removes old asphalt from a 2-kilometer section. The paver lays a 10-cm layer of new HMA, using a laser system to maintain thickness. Dump trucks wait to unload more HMA, and three rollers work in sequence: initial (double drum), intermediate (pneumatic tire), and final (double drum). Quality control technicians check temperature, thickness, and compaction to ensure compliance.