People forget what powered the world they live in, with cell phones, air conditioners, lights and provided electric power to myriads of industries and transportation systems. The world was a coal-based power generation. Without it, people would not be enjoying the luxuries they now enjoy. People plug into a wall outlet and like magic, they can run an appliance.
Some people make decisions with no information, meaning that there is a high likelihood they will be wrong. With information, this probability can be shifted more towards the lower end of the spectrum. So, when does the decision need to be made? Can it wait a little so that more information is available before making the decision?
Over one of the company’s engineers’ 50 years’ experience, the biggest disappointment they have witnessed is the loss of know-how due to people leaving or companies closing their doors. Technological advances have come and gone and yet it seems like the industry is constantly reinventing the wheel. How is this regained? The coal industry is highly competitive, which means that if technology and information is kept secret a miner can keep a competitive edge. The problem with this approach is that the technology may get lost, technology which includes computer programmes. Some companies invested in a staff of computer programmers that wrote all their software. As new computer platforms came along, the software was being constantly modified to adapt the software. Much of the mining software is now lost because it has not been kept up with new operating systems. Some of the old discarded software is better than preserved software available in the market today.
In the mining industry, advances have been made that will improve safety, for example underground ventilation or ground controls that can benefit everyone. The software that was developed could save lives and, if shared, would have the capability to benefit everyone. Some companies are spending more money on research and development than others. Contributing to these companies financially and redistributing technology that is safety related would help the world.
By using computer simulations, changing mining methods have been able to help turn a company that is losing millions of dollars into one which makes millions of dollars. In the 1970s, the US was landing men on the moon and thus space frontier was on everyone’s mind.
Deep underground in coal seams that were formed from compacted vegetation growing in swamps millions of years ago, underground surveyors were examining the locations of the mine faces so that the draftsman could generate maps. They drilled a 0.25 in. hole in the roof, hammered a wooden plug into the hole and then hammered in a metal spad with a hole in it, through a brass tag with a number on it. This number corresponded to a number on the map that the draftsman was generating, helping workers to locate underground mine development. They would hang a string with a plumb bob on it and shine their cap lamp behind it and the transit-man would tell them to tap the spad to the right or left to get the string at the correct alignment. The shift foreman would then use the same spad to hang a string and line up the entries underground.
One ‘conventional’ mine that was surveyed by underground surveyors had coal that was 50 in. thick. Each coal face was cut at the bottom with a cutting machine, drilled, blasted and then cleaned up with coal loading machines. The coal was then hauled from the coal face to railcars using an electric shuttle car. After the area was cleaned up, a roof bolter would drill the entry roof and place anchor bolts to support the roof.
The second mine surveyed was using a large coal cutting machine called a boring machine.
The boring machine was very large and slow. It would cut 100 ft of coal before it could move to another location. The circular shape of the entry left by the borer had enough stability to support the roof until the roof bolter could get in and bolt the roof. However, due to the slow cutting, the boring machine dumped the coal on the ground behind the machine so that it could continue cutting. A low profile (scoop) loading machine was used to gather the coal and convey it into waiting shuttle cars.
The boring machine also presented multiple dangers and health and safety hazards. This is because the machine is blocked by the pile of coal and could not be moved to the next location until the coal behind it was cleaned up. In addition, the mine operator, loading machine operator and the shuttle-car operator were all working under unsupported roof.
In the 1970s, the Mine Health and Safety Act passed laws that required coal mines to improve safety. One of the new rules was that no man could go beyond unsupported roof. This law eliminated the use of boring machines and required that continuous mining machines be more mobile.
The third mine that was surveyed was using these new, safer ripper machines (Figure 2). The depth of cut was reduced to the distance between the tip of the cutting head to the protected cab that the operator sat in. The cutting head is very narrow so, although it was a more mobile machine, it required many slices into the coal to carve out an entry.
Later, a full-face continuous miner was introduced that allowed for one cut before moving on to the next cut. As the laws changed, operators had to adjust their operations in order to stay in business. Satellite bolters were added on the sides of the continuous miner to simultaneously allow for bolting to be done and the continuous miner to cut coal. A centre bolter was used to bolt the middle of the entry after the continuous miner was moved to the next location to cut. The satellite bolters placed the roof bolter operator in a dangerous location as they stood between the mining machine and the ribs.
Read the article online at: https://www.worldcoal.com/special-reports/14052020/mind-the-digital-gap/