A pulverizer is a hydraulically operated jaw attachment mounted on the stick of an excavator, used to crush reinforced concrete and masonry into fragments suitable for recycling. The attachment closes two opposing jaws around a concrete element, breaking it apart while separating embedded reinforcing steel from the concrete matrix.
Design and Function
The pulverizer consists of a steel housing with a fixed and a moving jaw, driven by one or two hydraulic cylinders. The jaw faces carry replaceable crushing teeth or plates. As the jaws close, compressive force breaks the concrete into pieces while rebar is bent and exposed rather than cut. Many models allow jaw sets to be rotated or exchanged between primary (first-pass, heavy structural concrete) and secondary (sizing, reinforcement liberation) configurations. A hydraulic rotation unit (typically 360° continuous) is standard on most models, allowing the operator to orient the jaws without repositioning the carrier.
Technical Parameters
Pulverizers are offered in size classes matched to carrier weight, commonly from 12 t to over 90 t excavators. Typical operating weights range from roughly 800 kg for compact units up to 9,000 kg for large demolition-class attachments. Jaw opening widths range from approximately 300 mm on small units to 900 mm on large primary pulverizers. Crushing force at the tip is specified by manufacturers and varies by model and jaw geometry, generally increasing toward the jaw hinge. Hydraulic flow and pressure requirements typically fall in the range of 80-400 l/min and 280-350 bar, depending on carrier size.
Applications
Pulverizers are used in building demolition, bridge deck removal, and concrete recycling operations. By crushing concrete in place and exposing rebar, they allow separation of steel and concrete fractions on site, reducing material that must be processed off site. Processed concrete fragments are typically fed into mobile or stationary crushers to produce recycled aggregate. Compared to hydraulic hammers, pulverizers generate less noise, vibration, and airborne dust, which makes them preferred for demolition in occupied or sensitive environments.
Distinction from Demolition Shears
Pulverizers and demolition shears are often confused but serve different purposes. A pulverizer crushes concrete and masonry, deforming embedded rebar to expose it without severing it in a single stroke; its jaws are shaped for compressive crushing. A demolition shear is designed to cut steel sections, rebar, and structural steel through a shearing action between hardened blades, generating high cutting force concentrated at the blade edge. Shears are selected for steel-frame demolition, scrap processing, and rebar cutting, while pulverizers are selected for concrete and masonry structures. Some manufacturers offer combination or multi-processor jaw sets that can switch between crushing and shearing functions by exchanging jaw inserts.
Selection Criteria
Selection depends on carrier tonnage, required jaw opening relative to element thickness, hydraulic flow and pressure available from the carrier, and the proportion of reinforcement in the structure to be demolished. Jaw tooth geometry and wear plate material affect service life when processing abrasive or heavily reinforced concrete. Planners and contractors typically verify hydraulic compatibility between attachment and carrier before specifying equipment for a project.