Post by John on Mar 15, 2015 11:23:24 GMT -5
So whats the difference between UK coal mines and Miscellaneous mines elec equipment?
Not really a lot, as heavy duty elec equipment was only made for collieries, so at BG's Marblaegis Gypsum mine, we used "cast off old NCB switchgear, usually old OCB pedestal HV breakers of various makes for the 3.3Kv circuits, ancient GEB's of many makes for the C/V belts, drill rigs and other equipment, control gear was sometimes "home brewed" other times industrial in fabricated steel boxes. All motors were totally enclosed fan cooled, with the odd FLP ex NCB motors.
It was a gas free, none flammable environment, naked flames were allowed, in fact welding and burning was carried out, plus the lads smoked U/G, which was strange for me at the beginning.
CPL's Boulby was a different kettle of fish, operated under safety lamp rules as we had methane, sometimes enough to power a small town! In blow outs after shot firing operations.
So all equipment was FLP and IS, although pit bottom skipping cubicle was a standard sheet metal cubicle, always puzzled me that one did.
All vehicles had flame traps and scrubber tanks, burning and welding was allowed in the underground workshops, but had to be tested by a mining supervisor for methane.
We used restricted neutral on the transformers with SEL on all GEB's and breakers. Aux fans were Engart, the US made Stamler feeder Breakers and Joy cutters were re certified by the HMI for use in a gassy atmosphere.
Conveyor control was done with Huwood Mk1A FLP control GEB's with IS indicator board.
All main road and face communications was with the DAC intercom system with built in nicad batteries, telephones were all IS.
NSW in Australia was similar to the UK M&Q Act, but, all outbye intake electrical equipment was industrial, everything within 300 feet of a working face, listed as a hazardous zone, had to be flameproof/IS and any pumps, cable couplers etc in the return air had to be FLP.
Locos, both electric and diesel was certified to be FLP, as were the battery personnel carriers as they could go into the returns.
Transformers, other than those in a hazardous zone, were oil cooled and had to sit in a "pan" that could contain all the oil should the tank get ruptured.
The Coal Mine Regulation Act (CMRA) required the star point of the secondary side of the transformer to have a device to limit the fault current of a ground fault to be limited to a max of 5 amps, so we had an inductor in series with the star point and earth. (restricted neutral).
All longwall GEB's had SEL earth protection, when I started at Angus Place they were Wecol A67 GEB's, later on the new face set up, it was an Australian Make CMA, a copy of the Baldwin Francis GEB's Probably under license.
Authorization of HV switching U/G for maintenance differed with the different companies, At AI&S a division of BHP pty, it was always done with a shift engineer and an appointed electrician or elec leading hand, always two authorized elec personnel as a safety measure.
Angus Place was owned by the NSW government, who also operated several other mines around the state for power station coal. Not sure of the other pits routines and rules, but Angus Place usually operated with a permit to work, handed to the Leading hand Elec for isolation and earthing of the 11Kv outgoing circuit, issued by the previous shift elec engineer.
Now comes the problem, night shift didn't have an elec engineer, as it wasn't a production shift, so the leading hand elec was authorized to isolate and earth 11Kv circuits
Always made me nervous when I was leading hand, so for extra safety, I always took one of my electricians with me and we double checked the isolation procedures.
So there's a run down on UK coal, Misc mining and a comparison of NSW coal mines electrical gear.
Not really a lot, as heavy duty elec equipment was only made for collieries, so at BG's Marblaegis Gypsum mine, we used "cast off old NCB switchgear, usually old OCB pedestal HV breakers of various makes for the 3.3Kv circuits, ancient GEB's of many makes for the C/V belts, drill rigs and other equipment, control gear was sometimes "home brewed" other times industrial in fabricated steel boxes. All motors were totally enclosed fan cooled, with the odd FLP ex NCB motors.
It was a gas free, none flammable environment, naked flames were allowed, in fact welding and burning was carried out, plus the lads smoked U/G, which was strange for me at the beginning.
CPL's Boulby was a different kettle of fish, operated under safety lamp rules as we had methane, sometimes enough to power a small town! In blow outs after shot firing operations.
So all equipment was FLP and IS, although pit bottom skipping cubicle was a standard sheet metal cubicle, always puzzled me that one did.
All vehicles had flame traps and scrubber tanks, burning and welding was allowed in the underground workshops, but had to be tested by a mining supervisor for methane.
We used restricted neutral on the transformers with SEL on all GEB's and breakers. Aux fans were Engart, the US made Stamler feeder Breakers and Joy cutters were re certified by the HMI for use in a gassy atmosphere.
Conveyor control was done with Huwood Mk1A FLP control GEB's with IS indicator board.
All main road and face communications was with the DAC intercom system with built in nicad batteries, telephones were all IS.
NSW in Australia was similar to the UK M&Q Act, but, all outbye intake electrical equipment was industrial, everything within 300 feet of a working face, listed as a hazardous zone, had to be flameproof/IS and any pumps, cable couplers etc in the return air had to be FLP.
Locos, both electric and diesel was certified to be FLP, as were the battery personnel carriers as they could go into the returns.
Transformers, other than those in a hazardous zone, were oil cooled and had to sit in a "pan" that could contain all the oil should the tank get ruptured.
The Coal Mine Regulation Act (CMRA) required the star point of the secondary side of the transformer to have a device to limit the fault current of a ground fault to be limited to a max of 5 amps, so we had an inductor in series with the star point and earth. (restricted neutral).
All longwall GEB's had SEL earth protection, when I started at Angus Place they were Wecol A67 GEB's, later on the new face set up, it was an Australian Make CMA, a copy of the Baldwin Francis GEB's Probably under license.
Authorization of HV switching U/G for maintenance differed with the different companies, At AI&S a division of BHP pty, it was always done with a shift engineer and an appointed electrician or elec leading hand, always two authorized elec personnel as a safety measure.
Angus Place was owned by the NSW government, who also operated several other mines around the state for power station coal. Not sure of the other pits routines and rules, but Angus Place usually operated with a permit to work, handed to the Leading hand Elec for isolation and earthing of the 11Kv outgoing circuit, issued by the previous shift elec engineer.
Now comes the problem, night shift didn't have an elec engineer, as it wasn't a production shift, so the leading hand elec was authorized to isolate and earth 11Kv circuits
Always made me nervous when I was leading hand, so for extra safety, I always took one of my electricians with me and we double checked the isolation procedures.
So there's a run down on UK coal, Misc mining and a comparison of NSW coal mines electrical gear.