Maintaining and Sourcing Parts for Legacy Asphalt Pavers

[MikePhua]

The Evolution of Asphalt Pavers and Their Component Demands
Asphalt pavers have undergone dramatic transformation since their inception in the 1930s, when Barber-Greene introduced the first mechanical spreader. Over the decades, manufacturers like Caterpillar, Blaw-Knox, Roadtec, and Vögele refined the design, integrating hydraulic systems, electronic controls, and modular screeds. Despite these advancements, many contractors still rely on older models for their durability and simplicity. Machines built in the 1980s and 1990s—such as the Blaw-Knox PF series or early Cat AP models—remain in service across municipal fleets and small paving outfits.
These legacy machines, while mechanically robust, pose challenges in parts sourcing. Wear components such as augers, conveyor chains, screed plates, and track assemblies degrade over time and require replacement to maintain performance and safety.
Critical Wear Components and Their Functions
Key parts that require regular inspection and replacement include:

• Augers
  Responsible for distributing asphalt evenly across the screed width. Worn auger flights lead to inconsistent mat thickness and poor edge definition.
  
• Conveyor chains and sprockets
  Drive the flow of asphalt from the hopper to the augers. Chain stretch or sprocket wear can cause slippage and uneven feed rates.
  
• Screed plates
  Directly contact the asphalt surface. Made from hardened steel or composite alloys, they must maintain flatness and thermal conductivity for proper compaction.
  
• Track assemblies
  Provide traction and stability. Rubber tracks are quieter and gentler on surfaces, while steel tracks offer superior durability in abrasive environments.
  
• Bearings and bushings
  Found throughout the undercarriage and auger assemblies. Failure leads to vibration, misalignment, and premature wear of adjacent components.
  
• Flight bars and floor plates
  Guide asphalt flow and protect the paver’s internal structure. These are often made from Hardox 400 or 500 steel for abrasion resistance.
  

A contractor in Ohio once reported that replacing worn screed plates with precision-formed Hardox steel improved mat smoothness and reduced fuel consumption due to better heat retention.
Sourcing Strategies for Obsolete and Custom Parts
Finding parts for older pavers requires a blend of creativity and technical knowledge:

• Aftermarket suppliers
  Companies like DMC Wear Parts and Asphalt Solutions of America offer custom-fabricated components tailored to specific models. These often outperform OEM parts in durability and fit.
  
• Industrial part cross-referencing
  Conveyor chains, bearings, and sprockets can be matched by pitch, bore, and tooth count using catalogs from general industrial suppliers.
  
• CAD-based fabrication
  Some vendors use 3D modeling to reverse-engineer parts from worn samples, enabling precise reproduction even when original drawings are unavailable.
  
• Salvage and rebuild networks
  Regional equipment yards and rebuilders often stock discontinued parts or donor machines. Joining contractor forums and trade associations can yield valuable leads.
  
• Preventive stocking
  Maintaining a small inventory of high-wear items—especially augers, chains, and screed plates—reduces downtime and avoids emergency sourcing.
  

Maintenance Practices to Extend Component Life
Routine care can dramatically extend the lifespan of paver components:

• Clean conveyor tunnels and auger boxes daily to prevent asphalt buildup
  
• Grease bearings and bushings per manufacturer intervals
  
• Inspect track tension and alignment weekly
  
• Replace worn flight bars before they damage floor plates
  
• Monitor screed temperature and replace thermocouples as needed
  
• Use anti-stick coatings on screed plates to reduce drag and fuel use
  

Some operators retrofit their machines with digital temperature sensors and vibration monitors to detect wear before failure occurs.
A Story from the Field
In 2022, a municipal paving crew in Alberta faced repeated conveyor chain failures on a 1995 Blaw-Knox PF5510. OEM parts were no longer available. After measuring the chain pitch and sprocket dimensions, they sourced replacements from an agricultural supplier and fabricated custom mounting brackets. The retrofit not only restored function but improved feed consistency. The crew later documented the process and shared it with neighboring districts.
Conclusion
Maintaining legacy asphalt pavers is a balance of mechanical insight, sourcing ingenuity, and proactive care. While OEM support may fade, the machines themselves remain capable when equipped with quality parts and thoughtful upgrades. In the world of paving, precision begins with the parts beneath the mat. When the augers turn true and the screed glides smooth, the road ahead is built to last.