Designing a Tracked System for a Wheeled Trailed Industrial Grinder for Self-Propulsion

[MikePhua]

The evolution of industrial grinders – heavy-duty machines primarily used for processing wood waste, biomass, and other recyclable materials – has entered a new phase with innovation in mobility solutions. Traditionally, these grinders are wheeled and towed by external vehicles, limiting onsite mobility, efficiency, and operational flexibility. To address these limitations, a tracked undercarriage design for a wheeled, trailed industrial grinder enables self-propulsion and improved maneuverability over rough terrain.
Background and Machine Overview
Industrial grinders like the 4000 series weigh approximately 39,000 lbs, including a significant tongue weight of about 11,000 lbs when towed. The wheeled design generally offers good transportability on paved roads but falls short in soft, uneven, or heavily obstructed terrains. Large manufacturers, such as Vermeer, have taken strides by launching tracked versions of their horizontal grinders, like the HG4000TX, featuring durable track systems combined with high-horsepower CAT diesel engines, enabling these machines to tackle diverse job sites with low ground pressure and enhanced traction.
Challenges of Retrofitting a Tracked System
Converting a wheeled grinder to a tracked system involves engineering complexity due to the high machine weight and tongue load. The design must incorporate:

• Structural reinforcements to distribute weight evenly on the tracks without overstressing the frame.
  
• A drive system capable of transmitting power efficiently to both the tracks for propulsion and to the grinding components for processing.
  
• Suspension elements to absorb shocks and vibrations transmitted through rough terrain while maintaining stable operation.
  
• Steering or maneuvering mechanisms adapted to tracked movement, which differs significantly from wheeled steering.
  
• Management of hydraulic or electric power supplies for track motors, integrating with existing control systems.
  

Design Considerations and Solutions

• Track System Selection: Heavy-duty steel tracks with rubber pads provide durability and reduce ground compaction. Track length and width are calibrated to support the machine’s mass while preserving a manageable ground pressure to avoid sinking in soft soils.
  
• Drive Motors and Power Transmission: Hydraulic track motors driven by the grinder’s existing hydraulic system or supplementary pumps enable independent movement control for each track. Using dual motors also facilitates zero-radius turning capabilities, enhancing maneuverability.
  
• Weight Distribution: Counterweights or repositioned components may be needed to balance the additional weight on the rear tracks, especially since the tongue end bears a significant load.
  
• Crawler Frame Modifications: Custom-built track frames with mounts for the main machine chassis, providing secure anchorage for the tracks and absorbing torsional stresses during operation.
  
• Control System Integration: Operators require intuitive controls to switch between towing mode and tracked propulsion. The interface is often upgraded with safety features like automatic speed regulation and emergency stops.
  

Technical Terms

• Ground pressure: The pressure exerted by the machine on the surface, critical to prevent sinking or damaging soft ground.
  
• Hydraulic track motor: A motor powered by hydraulic fluid to drive a single track, providing propulsion and steering on tracked vehicles.
  
• Zero-radius turning: The ability of the tracked system to pivot in place, vital for negotiating tight job site spaces.
  
• Suspension system: Components designed to absorb shock and vibrations, important for maintaining machine integrity and operator comfort.
  

Real-World Applications and Benefits
Tracked grinder conversions or track-equipped models allow contractors to:

• Access remote or environmentally sensitive sites with minimal ground disturbance.
  
• Improve onsite productivity by self-moving without external towing vehicles.
  
• Simplify logistics by reducing the need for additional transport equipment.
  
• Increase machine uptime and reduce operational delays caused by difficult terrain.
  

For example, a forestry contractor installing a tracked undercarriage on a standard wheeled grinder reported a 30% increase in site coverage per day due to better mobility and less downtime caused by getting stuck or returning for haul vehicles.
Maintenance and Operational Tips

• Regular inspection of track tension and condition to avoid premature wear.
  
• Hydraulic system checks to ensure proper pressure supply to track motors.
  
• Lubrication of track rollers and drive sprockets to reduce friction and heat buildup.
  
• Environmental adjustments such as adding mud guards to prevent debris buildup.
  

Industry Insights
Manufacturers like Vermeer have pioneered factory-built tracked grinders, incorporating smart technology such as telemetry monitoring for machine health and productivity metrics, alongside power-saving engine controls. Still, many operators and smaller companies consider aftermarket tracked systems for retrofitting existing grinders due to cost and customization options.
Summary Recommendations

• Conduct a comprehensive structural assessment before retrofitting tracked systems on wheeled grinders.
  
• Choose track dimensions and motor capacities based on machine weight and expected terrain.
  
• Incorporate safety mechanisms for operator control and emergency shutdown.
  
• Plan for periodic maintenance focusing on hydraulic components and undercarriage parts.
  
• Utilize manufacturer support or consult engineering experts to ensure system compatibility.
  

In conclusion, integrating a tracked system into a wheeled, trailed industrial grinder transforms the machine from a tow-dependent unit to a self-propelled powerhouse capable of tackling diverse and challenging environments with improved efficiency, safety, and flexibility. This upgrade represents the future of mobility in heavy grinding equipment, blending mechanical ingenuity with practical operator benefits.