Rotary demolition shears

hydraulicfor construction equipmentfor excavators

Overview
Selecting an excavator hydraulic shear requires assessing the carrier beyond its gross weight. Prioritize the carrier's main pump flow and maximum operating pressure when matching a shear. Cutting force, jaw opening, jaw geometry and blade material determine daily productivity in scrap yards, demolition and ship‑breaking applications.

Shear types and comparison
Single cylinder shears use a single hydraulic ram with mechanical linkages to multiply force while keeping attachment weight lower. Dual cylinder shears employ twin rams for balanced, high crushing force suited to heavy concrete and structural steel. Eagle‑beak shears feature deep curved jaws that penetrate and slice thick beams and heavy scrap steel more effectively.

Where contractors use an excavator shear

• Scrap metal yards and auto demolition: Eagle‑beak types cut I‑beams, steel pipes and car frames rapidly to increase sizing throughput.
• Building demolition and concrete crushing: Dual cylinder shears bite through columns and slabs and separate rebar from concrete for material recycling.
• Underwater cutting and ship breaking: Heavy‑duty shears mounted on long‑reach excavators slice hulls and clear steel piles underwater.
• Site clearance and attachment teams: Shears reduce structural steel to manageable pieces; they are often used with screening or crusher attachments to process rubble and recover aggregate.

Matching an excavator shear to your machine size
Ensure balance between arm payload, boom strength and hydraulic pump output. Undersized hydraulics cause slow jaw cycles; oversized attachments overload the boom. Consider carrier weight, maximum system pressure and flow (L/min) to select the correct shear type and size.

Shear selection guide

• Single cylinder shear: Carrier weight 12–20 T; Operating pressure 28–32 MPa; Flow 120–180 L/min; Typical use: light plant demolition, rebar sizing.
• Dual cylinder shear: Carrier weight 18–35 T; Operating pressure 30–35 MPa; Flow 160–250 L/min; Typical use: building demolition, heavy concrete crushing.
• Eagle beak shear: Carrier weight 20–50 T; Operating pressure 32–35 MPa; Flow 200–350 L/min; Typical use: heavy scrap steel processing, car dismantling, ship cutting.

Operator tips and maintenance notes
Feed material into the throat to use maximum pivot force; avoid cutting with jaw tips on thick plate flanges. Rotate four‑edged cutting blades regularly and use all edges before replacement to reduce wear costs. Bolt‑on blade systems allow fast swaps, typically under one hour with standard tools.

Frequently asked technical questions

• Rotating vs fixed shears: Rotating shears provide 360° positioning for complex demolition tasks; fixed (non‑rotating) shears have simpler frames, lower upfront cost and suit ground‑based scrap processing yards.
• Blade life: Blade lifetime depends on material hardness and abrasiveness; operators commonly rotate four‑edged blades every 300–500 hours under typical scrap conditions.
• Hydraulic flow vs cutting force: System pressure sets peak cutting force; hydraulic flow controls jaw cycle speed. Low flow does not reduce peak force but will slow cycles and lower hourly throughput.

Technical characteristics / specifications

• Product type: Excavator hydraulic shear (single cylinder, dual cylinder, eagle‑beak)
• Carrier weight ranges: 12–50 T depending on shear type
• Operating pressure ranges: 28–35 MPa
• Hydraulic flow ranges: 120–350 L/min depending on shear type
• Primary applications: scrap processing, car dismantling, building demolition, concrete crushing, underwater ship cutting
• Blade design: four‑edged, bolt‑on cutting blades (rotate edges to extend life)
• Blade maintenance: rotate every 300–500 hours depending on material; bolt‑on replacement typically under 1 hour
• Operator recommendations: feed material into throat for maximum pivot force; select shear type based on steel thickness, pump flow and carrier capacity