Unformatted text preview: udinal (Auger) type
Borer type. 10.2.1 RIPPER (TRANSVERSE) TYPE ROADHEADERS – (CUTTER HEADS
WITH ROTATION PERPENDICULAR TO THE BOOM AXIS)
In ripper type the full weight of the machine acts as the counter reaction for the cutter
head. The rock is ripped off the face and thrown on the gathering head. Miner shown
in figure 10.3 utilizes the weight of machine as the reaction force for cutting in a better
way than the milling type of roadheaders, and no bracing jacks ‘stells’ are required.3
These machines have 20–35% lower weight (which means lower price) than boom
type roadheaders of equivalent capacity. In USA 75% of the road headers are of ripper
type.3 Ripper type roadheaders can be further classified as: Bar & Disc types (fig.
10.2(a) & (b)).
10.2.1.1 Bar type Its cutting element consists of a ripper bar, or cutting head that tears the coal/rock from
the face. The cut rock/coal is carried by the moving chains and discharged into an intermediate conveyor. The rock/coal that falls on the floor is pick...
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- Spring '14
- Francis Group, Taylor & Francis Group, Excavator, roadheaders