conveyor will push as determined by SRB parameter “H->T Push Stroke”. This will usually be set to 100. The picture below shows the longwall state as the shearer cuts back towards the tailgate. Full-Web Cycle – Step 3 – Cutting Head to Tail
The full push will follow the shearer all the way to the TG until the entire conveyor is pushed. The picture below shows the longwall state when the shearer reaches the tailgate. Full-Web Cycle – Step 4 – Shearer in Tailgate
When the shearer reaches the tailgate, it will again be a full-web in the coal. The coal face has one snake (at the tailgate), the shields are straight and the conveyor is completely pushed on the entire face. The longwall is in the same state as the Initial Position picture shown previously. The system is ready for the shearer to go back to the headgate and repeat the entire cycle.
Shearer Cleanup Problems If the shearer does not clean-up sufficiently to allow the shields to push to a full 100% stroke, the parameter “H->T Push Stroke” can be set to a lower value, such as 90%. In the above description, the phrase “completely push” or “full push” refers to this value. The tailgate pushes to this value as the shearer is cutting to the head, and the rest of the face will push to this value on the head to tail pass.
Bidirectional Cutting Cycle SRB parameter “Cycle” must be set to “BIDI” to use SRB in a bidirectional cutting cycle.
Parameter “Cycle”
When using the bidirectional cutting cycle, the shearer cuts the entire top and bottom coal, full depth, as it travels in both directions. In both directions, the shields are advanced and the conveyor is pushed. When the shearer reaches the endgate, a double cut is required to keep the gates even with the rest of the face. © Caterpillar
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