Post by dazbt on Aug 23, 2008 6:01:45 GMT -5
Who reckons that all colliery managers lose their sense of humour in the face of adversity? ……… well not all of em do;
at a time shortly before its demise in 1983, Newmarket Silkstone Colliery on the outskirts of Wakefield in West Yorkshire made one final effort to try and offset the inevitable shroud of closure, a last chance thin seam longwall installed with an AM 420 Buttock Shearer, practically a prototype machine that in fairness was still in the throes of its primary development.
I believe that the extracted section was 32inches but in reality for much of the face length the coal was only about 14 inches thick which obviously didn’t provide a great promise of success. But, in fairness to the shearer, when it was cutting it tackled the 18 inch of ‘rock’and ‘sliver’of coal pretty well, the only problem being that the machine was rarely in a condition to cut anything, just about everything that could go wrong from a technical point of view, did go wrong. From a service engineer’s point of view it was a nightmare, from a field development engineer’s standpoint this was the machine from Hell, the very mechanical contrivance project that makes, suicide seem to be the better option on a frequent basis. The very concept of high horsepower shearers being able to work in seam sections as thin as this is practically an engineering contradiction, but in fairness the AM420 was one of the few machines that did eventually develop to be able to achieve this. The basic design necessitated by the application of large capacity electric motors and gearheads capable of transmitting the developed power in thin seams, meant that every inch of available practical space was utilised, the machine body had to be face side floor mounted to provide height for the machine depth, it then followed that the cutting drums had to be in line with the machine body, completely away from the original concept of the Anderton shearer offset drum, and this factor then put the face side of the machine body extremely close up to the coal face. Prop Free Front was a problem because there was insufficient roof above the shearer body to place roof supports, the machine controls had to be brought to the goaf side to enable manual control, in order to protect these control extensions a robust canopy had to be incorporated to protect them over the AFC whilst still allowing sufficient coal clearance underneath them and they were only the easy bits ……………..
Other incorporated concepts such as Roll Rack chainless haulage systems being used for the first time in thin seams and on the face side of the AFC, along with a brand new and extremely complicated sensory dual (Slave and Master) hydraulic haulage system, plus a brand new electronic automatic roll steering system just added to the complications. Maintenance, fault finding and repair difficulties were magnified by the inherent problems of minimal clearance to all aspects of this machine, the obvious problems of not being able to access over the top of, behind or even from the goaf side of any machine section proved to be a major set back.
Anyway back to the story, shortly before it was accepted that this Colliery was in its final throes and defeat sadly having to be admitted, after a particularly bad week of machine breakdowns and pathetic tonnages as a direct result of them, I was called back to the pit (after just getting into bed after a 22 hour shift underground sorting out some problem or other with the shearer) to attend an emergency meeting called by the manager, when I arrived, a quick glance round all the BC representatives who had also been called, area coal face engineer, area electrical and mechanical engineers, colliery electrical and mechanical engineers and what seemed like a dozen other well dressed people, left me in no doubt that this was pretty serious stuff, we were eventually ushered into the conference room, all served with coffee and biscuits, we were seated around the table, everybody being polite but knowingly waiting for the explosive entrance of the almost notorious colliery manager. The lady secretary entered the room and distributed to everyone there a foolscap page, with a list, numbered one to six, from memory the list started;
1) The machine will not start low oil switch
2) The machine will not start motor thermal trip
3) The machine will not start retaining relay
4) The machine will not start hydraulic oil thermal trip
5) The machine will not start low water flow
6) The machine will not start pilot circuit fault.
To start the shearer and actually cut coal, please refer to page two,
there wasn’t a page two, everybody round the table read the first sheet and although the discussion was polite no-one understood what it was all about, at this point the conference room door was kicked open and in walked the infamous colliery manager, who said nothing, he simply walked to the head of the table and simultaneously with his secretary distributing page two to everyone sitting round the table, he calmly, (but totally unlike him) produced a very professionally made huge cardboard dice and rolled it down the full length of the table, simply asked, “Tell me gentlemen just how you expect me to keep this pit open with odds like these?” ………….
the second page simply said;
“To Start the Shearer ……………….. Shake a Seven”,
I reckon he was just about right, but the meeting went on for hours.
at a time shortly before its demise in 1983, Newmarket Silkstone Colliery on the outskirts of Wakefield in West Yorkshire made one final effort to try and offset the inevitable shroud of closure, a last chance thin seam longwall installed with an AM 420 Buttock Shearer, practically a prototype machine that in fairness was still in the throes of its primary development.
I believe that the extracted section was 32inches but in reality for much of the face length the coal was only about 14 inches thick which obviously didn’t provide a great promise of success. But, in fairness to the shearer, when it was cutting it tackled the 18 inch of ‘rock’and ‘sliver’of coal pretty well, the only problem being that the machine was rarely in a condition to cut anything, just about everything that could go wrong from a technical point of view, did go wrong. From a service engineer’s point of view it was a nightmare, from a field development engineer’s standpoint this was the machine from Hell, the very mechanical contrivance project that makes, suicide seem to be the better option on a frequent basis. The very concept of high horsepower shearers being able to work in seam sections as thin as this is practically an engineering contradiction, but in fairness the AM420 was one of the few machines that did eventually develop to be able to achieve this. The basic design necessitated by the application of large capacity electric motors and gearheads capable of transmitting the developed power in thin seams, meant that every inch of available practical space was utilised, the machine body had to be face side floor mounted to provide height for the machine depth, it then followed that the cutting drums had to be in line with the machine body, completely away from the original concept of the Anderton shearer offset drum, and this factor then put the face side of the machine body extremely close up to the coal face. Prop Free Front was a problem because there was insufficient roof above the shearer body to place roof supports, the machine controls had to be brought to the goaf side to enable manual control, in order to protect these control extensions a robust canopy had to be incorporated to protect them over the AFC whilst still allowing sufficient coal clearance underneath them and they were only the easy bits ……………..
Other incorporated concepts such as Roll Rack chainless haulage systems being used for the first time in thin seams and on the face side of the AFC, along with a brand new and extremely complicated sensory dual (Slave and Master) hydraulic haulage system, plus a brand new electronic automatic roll steering system just added to the complications. Maintenance, fault finding and repair difficulties were magnified by the inherent problems of minimal clearance to all aspects of this machine, the obvious problems of not being able to access over the top of, behind or even from the goaf side of any machine section proved to be a major set back.
Anyway back to the story, shortly before it was accepted that this Colliery was in its final throes and defeat sadly having to be admitted, after a particularly bad week of machine breakdowns and pathetic tonnages as a direct result of them, I was called back to the pit (after just getting into bed after a 22 hour shift underground sorting out some problem or other with the shearer) to attend an emergency meeting called by the manager, when I arrived, a quick glance round all the BC representatives who had also been called, area coal face engineer, area electrical and mechanical engineers, colliery electrical and mechanical engineers and what seemed like a dozen other well dressed people, left me in no doubt that this was pretty serious stuff, we were eventually ushered into the conference room, all served with coffee and biscuits, we were seated around the table, everybody being polite but knowingly waiting for the explosive entrance of the almost notorious colliery manager. The lady secretary entered the room and distributed to everyone there a foolscap page, with a list, numbered one to six, from memory the list started;
1) The machine will not start low oil switch
2) The machine will not start motor thermal trip
3) The machine will not start retaining relay
4) The machine will not start hydraulic oil thermal trip
5) The machine will not start low water flow
6) The machine will not start pilot circuit fault.
To start the shearer and actually cut coal, please refer to page two,
there wasn’t a page two, everybody round the table read the first sheet and although the discussion was polite no-one understood what it was all about, at this point the conference room door was kicked open and in walked the infamous colliery manager, who said nothing, he simply walked to the head of the table and simultaneously with his secretary distributing page two to everyone sitting round the table, he calmly, (but totally unlike him) produced a very professionally made huge cardboard dice and rolled it down the full length of the table, simply asked, “Tell me gentlemen just how you expect me to keep this pit open with odds like these?” ………….
the second page simply said;
“To Start the Shearer ……………….. Shake a Seven”,
I reckon he was just about right, but the meeting went on for hours.
