Overview
The Cat® Rock Straight System is a fully mechanized longwall system adopted to hard rock conditions for continuous mining of low seam hard rock deposits. The Rock Straight System combines the use of a hard rock shearer (Hard Rock Miner HRM220), a hard rock chain conveyor (Hard Rock Conveyor HRC30) and hydraulic roof support (Hard Rock Roof Support HRS1220). It features the unique adaptation of Caterpillar “Activated Undercutting Technology” and has been specifically designed for the extraction of bedded hard rock deposits (e.g. platinum, copper, gold). The Rock Straight System provides economical cutting in the mining of thin seams and narrow veins, especially when selective mining of ore is required.
Conveyor System
Units:
| Conveyor Capacity - Approximate | 176.0 tonnes/hr | 160.0 tonnes/hr |
| Note | 100 m (328 ft) conveyor length/varies with rock density. | 100 m (328 ft) conveyor length/varies with rock density. |
Dimensions (Approximate) - HRC30 Hard Rock Conveyor
| Apron Plate Chain Diameter | 30 mm × 108 mm (1.18 in × 4.25 in) | 30 mm × 108 mm (1.18 in × 4.25 in) |
| Apron Plate Spacing | 4 × 108 mm (4 × 4.25 in) | 4 × 108 mm (4 × 4.25 in) |
| Capacity per Hour | 176.0 t | 160.0 t |
| Chain Length - Up To | 328.0 ft | 100.0 m |
| Chain Speed | 2.3 ft/min | 0.7 m/s |
| Line Pan Height | 11.02 in | 280.0 mm |
| Line Pan Length | 102.95 in | 2615.0 mm |
| Line Pan Width | 69.13 in | 1756.0 mm |
Dimensions (Approximate) - HRM220 Hard Rock Miner
| Body Height | 47.2 in | 1200.0 mm |
| Cutting Depth - Up To | 3.9 in | 100.0 mm |
| Cutting Drum Speed | 60.0 r/min | 60.0 r/min |
| Cutting Head Diameter | 50.0 in | 1270.0 mm |
| Cutting Units | 2 | 2 |
| Installed Power Electrical System | 427.6 HP | 319.0 kW |
| Installed Power Hydraulic System | 73.7 HP | 55.0 kW |
| Installed Power per Cutting Unit | 177.0 HP | 132.0 kW |
| Machine Weight - Approximate | 45.2 t | 41.0 t |
| Operating Voltage | 1,000 V; 50 Hz; 3 AC | 1,000 V; 50 Hz; 3 AC |
| Seam Range | 1.3-2.0 m (4.2-6.6 ft) | 1.3-2.0 m (4.2-6.6 ft) |
| Typical Machine Length | 22.3 ft | 6.8 m |
Dimensions (Approximate) - HRS1220 Hard Rock Roof Support
| Base Width | 51.18 in | 1300.0 mm |
| Bearing Surface Base | 38.061 ft² | 35360.0 cm² |
| Canopy Extension Length | 59.05 in | 1500.0 mm |
| Canopy Width | 62.99 in | 1600.0 mm |
| DA (Double Acting) Ram Stroke | 24.6 in | 625.0 mm |
| Distance Roof Support Centers | 69.29 in | 1760.0 mm |
| Height - Closed | 41.73 in | 1060.0 mm |
| Height - Extended | 84.64 in | 2150.0 mm |
| Leg Centers Distance - Vertical to Face | 1440/1660 mm (56.69 in/65.35 in) | 1440/1660 mm (56.69 in/65.35 in) |
| Main Canopy Length | 166.93 in | 4240.0 mm |
| Support Resistance (at Height 1600 mm/62.99 in) - Load at the End of Swivel Canopy | 14.5 psi | 100.0 kN |
| Support Resistance (at Height 1600 mm/62.99 in) - Setting Load at 320 bar (4,641 psi) | 320.38 psi | 2209.0 kN |
| Support Resistance (at Height 1600 mm/62.99 in) - Yield Load at 415 bar (6,019 psi) | 376.95 psi | 2599.0 kN |
| Swivel Canopy Length | 59.05 in | 1500.0 mm |
| Weight | 10.25 t | 9.3 t |
Hard Rock Conveyor HRC30
| Conveyor System Length - Approximate | 328.0 ft | 100.0 m |
Hard Rock Miner HRM220
| Miner - Typical Machine Length | 22.3 ft | 6.8 m |
Hard Rock Roof Support HRS1220
| Roof Support - Height Extended | 84.64 in | 2150.0 mm |
Miner Machine Weight
| Weight - Total | 45.2 t | 41.0 t |
Power
| Miner Haulage Speed | 0-6 m/min (0-19.7 ft/min) | 0-6 m/min (0-19.7 ft/min) |
| Total Installed Power - Approximate | 938.0 HP | 700.0 kW |
Roof Support System
| Note | At height of 1600 mm (62.99 in) and setting load at 320 bar (4,641 psi). | At height of 1600 mm (62.99 in) and setting load at 320 bar (4,641 psi). |
| Support Resistance | 320.38 psi | 2209.0 kN |
Seam Height
| Minimum to Maximum Cut | 1.3 to 2.0 m (4.2 to 6.6 ft) | 1.3 to 2.0 m (4.2 to 6.6 ft) |
