What is a tub grinder?

Tub grinders are indispensable in the forestry and recycling industries, transforming organic materials like wood, brush, and agricultural residue into smaller particles. By downsizing these materials, tub grinders create valuable products such as mulch, boiler fuel, and compost, while also reducing material volume to cut transportation and disposal costs.

Drum grinders were originally used in green waste recycling to convert waste wood into boiler fuel. Later, their use expanded to landfills to reduce waste and to composting operations as a source of carbon-rich mulch. Today, drum grinders are widely used in the landscape mulch industry.

Available in various sizes and horsepower levels, tub grinders handle diverse green waste—including debris piles, logs, stumps, leaves, and construction debris (C&D materials)—with ease.

Key Components

Tub grinders are robust machines with intricate designs, but three components stand out: the mill, the engine, and the tub size.

The Mill

Typically cylindrical, tub grinder mills feature hammers on their surface, categorized as fixed or swing types. Fixed hammers excel at processing tough, large materials like logs and stumps, often paired with larger tub grinders. Swing hammers, meanwhile, are better suited for smaller materials like wood chips and bark. Grinder tips, mounted on the hammers, perform the actual grinding. Coated with tungsten carbide grit welded to their surface, these tips ensure durability and efficiency.

The Engine

The engine powers the grinder, and its horsepower dictates the range of materials it can process. High-powered engines are ideal for tackling logs and stumps, broadening the machine’s capabilities.

The Tub Size

Tub size influences the scale of supporting equipment, such as excavators and loaders. Selecting the appropriate size ensures smooth, efficient operation.