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Post by coalfire on Apr 27, 2009 8:16:24 GMT -5
O.K. understood. We have some stuff like that here never seen it on the top but, when I worked the Pocahontas#3 seam we had what you described on the bottom. We called it Fire clay. And your right when it got wet there was no bottom. Some people also called it soapstone. I guess it depended on what region they were from.
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Post by John on Apr 27, 2009 15:15:21 GMT -5
I tell you what Lannie, it's amazing how fast a good crew can advance driving a road "in the solid with a Dosco and setting "rings" every 3ft 6ins!! Having seen the same using roofbolts and a Dosco, there's not a lot of difference. I worked at Cleveland Potash's Boulby Mine in North Yorks before the No1 shaft was in full use. When I started there, all work was done with Joy undercutters, drilled faces with Secoma drill rigs, and bolted with Secoma drill rigs. The bords were fired and mucked out with Eimco LHD's to Stamler feeder breakers. (ratio feeders) onto 42 inch high speed belts. I saw some very odd things at that depth, 3/4 mile beneath the surface, roof creeping between the pillars, roof bolts shearing, the nuts flying off bolts due to the massive pressure on them! They now mine with Joy Continuous Miners, all main roads are in the salt seam beneath the potash seam now. It appears to be more stable than having the roads in potash.
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Post by John on Apr 29, 2009 16:09:42 GMT -5
Anyone work with the Dawson Miller Stablehole Machine?? I recall as an apprentice seeing training films with one based on the machine. Never saw one for real though.
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Post by dazbt on Jun 10, 2009 13:35:34 GMT -5
"Row over mine roof bolts after three die: 'Forum' on safety in wake of Bilsthorpe tragedy"Headlines resulting from a tragedy some years ago now but brought back up recently by someone asking for more info on the incident. See thenewspaper article here; news.independentminds.livejournal.com/3024073.html If I remember correctly the main conclusion to the 'investigation' stated that massive collapse of the gate was as a direct result of 'rib to rib' longwalling with insufficient width of block support being left between them. The incident itself and ensuing investigation result didn't exactly promote a greater faith in roof bolting in the UK.
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Post by John on Jun 10, 2009 17:44:55 GMT -5
Interesting Daz, we had a section of roadway bolted at Clifton, that was way back in the early 60's. I think it was an experiment. Bolts work, BUT, you have to have the strata, they have to be installed before bed separation sets in and the crews have to be experienced with bolts and stick rigidly with the Managers support rules! I've seen them fail many times, sometimes through installation error, a few times caused by convergence and the bolts sheared under tremendous weight. I wouldn't trust working in a UK colliery with them as the only means of support though!! Strata is too weak being mudstones. The roads in Australia are supplemented with props and half round bars plus "w" straps. Plus our strata was "massive sandstone's" that the bolts are installed in. Boulby Potash Mine in North Yorks used bolting extensively, saw a few failures there, mainly because bolts sheared under the tremendous loads they bore.
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Post by John on Jun 12, 2009 13:41:24 GMT -5
From what I've read of that accident since you posted it Daz, appears from witnesses that not only enough rib support was left, but the roads actually broke through to each other in many places. Extremely poor mining practice no matter what mineral is worked. The whole support system is lost. I was taught bolts are used to form a natural arch girder by binding the strata together so that the pillars either side can support the roof. Seems they lost one side of the main support. No wonder they had a catastrophic roof failure. There's some good info by the University of Wollongong on the internet carried out at my old pit over there, Angus Place. Since I left in 89, they have been having geological problems, actually the poor conditions started at the drivages of LW13 when I was there, but was thought to be just a "local" issue that would "go away".
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Post by John on Aug 28, 2009 6:12:35 GMT -5
While doing a little surfing yesterday I came across some useful history. The first shearer power loader was installed in a Lancashire colliery in 1954, two years later powered supports were introduced. I'd hazard a guess they were Dowty Roofmasters, although the book didn't say the manufacture. I copied the pages from the book "Inventions of the 20th Century" and will be posting them on my website. There's a photo of a Huwood Slicer Loader at Dinnington colliery and a Plough at Wernoi Colliery Wales on the pages too. Plus some ancient Dowty Roofmasters at Calverton Colliery, probably from the late 50's.
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Post by dazbt on Aug 30, 2009 11:06:25 GMT -5
I believe that the first powered support systems used in the UK were Seaman PS1 manufactured by Gullick in 1954 and although I thought originally that Dowty Roofmasters weren't introduced until the early 1960s I read that they were first installed in 1957. I do remember Roofmasters being used and recall how unstable they were to advance. It was around 1967 when I saw the first 'proper chocks', installed at South Kirkby on a 70hp Trepanner face ........... "Walking Clogs" they were called locally, I've no idea what type they were ...... but a half ounce twist of Murrey's Irish Roll bacca was 1s.11d at the time.
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Post by John on Aug 30, 2009 12:00:28 GMT -5
I believe that the first powered support systems used in the UK were Seaman PS1 manufactured by Gullick in 1954 and although I thought originally that Dowty Roofmasters weren't introduced until the early 1960s I read that they were first installed in 1957. I do remember Roofmasters being used and recall how unstable they were to advance. It was around 1967 when I saw the first 'proper chocks', installed at South Kirkby on a 70hp Trepanner face ........... "Walking Clogs" they were called locally, I've no idea what type they were ...... but a half ounce twist of Murrey's Irish Roll bacca was 1s.11d at the time. Your correct Daz, first Dowty's were installed in 1960, and Tom Seaman's designed Gullicks were patented on June 24th 1955. I often wondered why the Gullick chocks got the name "Seaman" until I discovered he was the designer of them. I've been locating tons of mining history from mid 20th century until the demise of the UK coal industry recently. I too didn't like the Dowty Roofmasters either, I always feared them when they were advanced, very top heavy and such a narrow base for such a heavy chock. I worked under two lots of Dowty's, both in the deep hard seam, one 48 inches high and one at the extreme west edge of the workings at just over 60 inches high.Both worked on hydraulic oil too, so wasn't too pleasant when a hose burst! After that I worked under German Westphalia chocks and Gullick 5 leg Seaman chocks. I've searched and searched for photos of Westphalia, Dobson double2's and Wild-Desford Goal Posts to no avail. Ironically, my late Dad used to deliver Dobson double 2's from their Colwick Works in Nottingham to pits in South Wales. I think I'll send an email to Gullick and see if they have any photos they can send me on the Dobson line, no doubt they would have inherited all that stuff when they and Dobson merged.
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Post by erichall on Sept 20, 2010 6:23:44 GMT -5
First 'mechanised face' I ever worked was at Barrow Colliery in S.Barnsley, and this was equipped with the then new Dobson Double-2's. machine wa sa floor mounted AB Trepanner. Seemed enormous at the time, especially in a 40inch seam
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Post by John on Sept 20, 2010 7:37:26 GMT -5
First 'mechanised face' I ever worked was at Barrow Colliery in S.Barnsley, and this was equipped with the then new Dobson Double-2's. machine wa sa floor mounted AB Trepanner. Seemed enormous at the time, especially in a 40inch seam I'd love a photo of the Dobson Double2's Eric!! Ironic, they were made at the Colwick Works in Nottingham and yet never used in any of the Nottingham pits! My Dad also delivered Dobson Chocks and hydraulic cylinders as a truck driver.
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Post by erichall on Sept 24, 2010 6:07:37 GMT -5
Arch sizes varied from pit-to pit and from area to area. Our usual sizes were 14x12 in Main gates and 12x10 in tail gates. these were always 4 piece arches, the face side leg being cut to allow a yielding fish plate to be set in the advance heading. This would be removed at the face entry, the leg being reused in advance and a slightly smaller leg being substituded along with normal fishplates behind the face as it advanced.
My first pit as Undermanager, however, used a style I had never seen before. The gate side packswould be formed using round props instead of the normal square chock nogs. The special arches were the standard arch with a cut off and a curved plate welded at approximately 3 feet. These were set on top of the prop built pack. it seemed peculiar, but proved very effective, and worked out faces could easily have their arches 'drawn off' and transported to an inbye 'arch straightening station' to be re-profiled before being reused.
With regard to shearers, which in our 30-40inch sections had proved to be the most effective machine, one AGM's idea was that you had a shearer on the face and another in parts in the tail Gate. Apart from oiling up and checking of the face machine, and the rectification of minor faults, the machine was put on the face, worked till it dropped, then dragged off the face and scrapped, whilst the new machine was quickly installed.
Our favourite machine , however, proved to be the AB Trepan Shearer. This was an AB 16 Shearer with an outboard Trepan Head. Almost invariably, the Trepan Head was the first to go, and when it did, the trepan Head was discarded, and the 'souped-up' Shearer continued to be used. More power than the ordinary shearer.
I was once told by a local bank Manager when I asked him why we couldn't attract business as the local pits were closing, and his reply to me was that 'there wasn't an available local workforce, because the Miners only knew how to mine coal.' This image was one that stayed around many coal minig areas, and was I think to some extent a view held by the miners themselves. He was amazed when I exploded and told him, in no uncertain terms, that the average miner could turn his hand to anything, and told him that, no matter what piece of new equipment was sent into the mines one thing happened. The miner, on being told what the equipment was to be used for 'AND ONLY THAT', invariably started to think of at least a dozen uses he could put it to apart from its designed purpose. The first thing a miner learns is to make do and mend. A more inventive race I have yet to see.
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Post by John on Sept 24, 2010 7:00:05 GMT -5
You're right there Eric, we had quite a few BSc's at Clifton, I was amazed at how many face men we had who held those academic qualifications, plus several who had class 1 tickets but were just happy doing what they were doing without responsibilities.
Clifton was the last pit in the area, probably Division!!! Still on the mech/elec scheme, the shearer drivers were often right when they diagnosed a pipe failure in the shearer haulage end and got on the tannoy for us to bring up a whatever number pipe with our tools!!
They were used to every noise that machine made and could tell you something was amiss before it finally gave up the ghost. Mind you, without the shearer they didn't make money back then, just about when the first new power loader agreement faces were starting up, 25 quid a week whether we turned coal or not./b]
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Post by John on Sept 25, 2010 9:15:10 GMT -5
I recall some "friction" rings we had on trial, if memory serves me right, the rippers called them "German rings" Three section, legs and crown, but instead of being plated and bolted just had long "U bolts" and a plate. The ring section was "U" in shape instead of "H" section. The crown went over the legs and was clamped with the "U bolts" and heavy flat plate. For some reason, probably cost, they weren't used for very long, but they didn't distort so easily as the standard rings did.
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ken
Trainee
Posts: 46
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Post by ken on Sept 27, 2010 2:54:01 GMT -5
When I worked at Easington many years ago we had a lot of these in use. We called them Park Gate girders which I thought was the name of the manufacturer. Ken
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