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18 www.coalage.com July/August 2017 longwall mining continued tem pressure, cylinder pressure, solenoid states), and it also has an alarm history. If we have any issues, the operators contact maintenance, and they can fix it quickly." The AFC screen shows voltages and cur- rents for the motors, coupling speeds, PTO switch, run commands and temperatures. "At the bottom, operators see the solenoid states, fill drain, and an indication for the pivoting tensioners in the headgate and tail- gate," Faykus said. "Whenever anything hap- pens, the operators refer to this screen and relay the information to face personnel." The DCM screen shows top-down in- coming pressure, the set and actual tension tonnage, monitored in the chain, the target and actual position of the tensioning jack, min-max position for the day, amps, the solenoids (increase and decrease), bottom center cylinder pressure and alarms. "If they have any problems with the chains, they can refer to either one of two screens and the shearer operators can relay the information to the personnel on the face," Faykus said. Faykus played a video of an in-house- designed graph, where a gray squiggly line showed the load pin as it reacts to the flights passing by. A yellow line indicated the stroke of the jack. A white line measured the ton- nage in the chain, while a green line showed an increase solenoid being fired. Red lines are used for decrease solenoids being fired. Purple indicated the cylinder pressure. "When we fire the increase solenoid, we get an increase cylinder pressure, the tons on the chain goes up and our stroke goes out and it indicates everything in the DCM is working properly," Faykus said. For shearer diagnostics, the operators primarily use the remote operations screen. It displays pitch and roll, drum pick height, speed and location, pump motor status, re- mote configuration for the Pacman (local or remote), and the sequence for ASA. From the remote operations screen, the shearer operators have the speed, lo- cation and the modes for the drum for when automation is engaged and the cowl is positioned. The remotes are configured with one Pacman on the face and one out- by. "The operators can see whether the left and right pump and cutter motors are run- ning," Faykus said. "It shows the pitch. It shows the target height where the ASA is wanting to put the arms and where they are actually located. They can see the so- lenoids firing to put the arm in position. The Joy home screen offers a quick overview of all of the Joy information, such as the motors, current, shearer location, the speed and DCM information, chain tension and stroke, etc. The operators can see all of the passes that have been made in the last 24 hours. Tailgate Turnarounds During a remote tailgate turnaround, the operator's attention turns to the Cat side. The shearer enters the tailgate and the shields advance. Across the bottom of the graph, the operators see blue and green squares pop up, which indicate everything is running fully automated. The three stag- gered shields advance in sequence. The first line will go and the shearer will drive out and cut a stump. The gate end will push out. Faykus noted that Tunnel Ridge worked with Cat on the tailgate readvance. As the shearer leaves the gate and goes back to the stump, everything will advance, Faykus ex- plained. The three gate shields readvance again. "This minimizes the top exposure and the tip-to-face distance," Faykus said. "As the shearer leaves, the gate shields and staggered shields will advance in sequence. As the shearer advances toward the head- gate, the gate shields push and the three on the end will readvance, and that helps keep the tailgate roof under control, especially with all of the remote mining." Conditions permitting, more than 95% of the time Tunnel Ridge runs tailgate turnarounds on remote. "They run it even when conditions get sketchy," Faykus said. "The Cat system handles all of that. We transfer the shearer position through seri- al to us and then we pass it to Cat." As far as the ASA in a tailgate turnaround, the operators working by remote are quick- er and more accurate than the automated shearer system. "The coal block and stop position change." Faykus said, "When they quit cutting top and shear down, we can't update the automation on every pass or two passes or even each shift. So, when they are using the cameras, they skip steps that we can't record and, when they hit the auto stop, only they can tell if they are far enough down to shear out and not shuffle. We can't assess all that data to make them change to automation every time. "They cut the tailgate on remote most of the time," Faykus said. "We developed shearer automation for the tailgate and it's something we run once a panel to make sure it still works." Currently, the headgate opera- tor does the turnaround at the headgate, al- though they could do everything on remote. As far as utilization, Faykus estimated that nearly 85% of the longwall coal is run through automated processes. "The sys- tem has been very robust," Faykus said. "We will occasionally run with cameras when the networks are down." Monitoring and Maintenance The operators also use the Cat screen to troubleshoot the shields. "In this example, you can see that we have no invalid sen- The Longwall Command Room on the surface has larger displays and better views than the Longwall Command Center underground.