Write short note on the following : Grader , Surface miner,Bucket wheel excavator

  GRADER   : Grader(or motor grader)is a mchine for grading,cleaning and leveling the houlroad.It does not lift the material,but just pushes the loose material or scrapes t material to level the ground.       

                                                                                                         

The wheel mounted diesel operated machine does all jobs with its long and strong blade has a replaceable cutting edge.                                                                    Surface miner  :  In India use of Surface Miner in coal mines started in 1999 at Lakhanpur OCP of MCL.Now surface miners are used in many open cast mines.                                                                              This crawler mounted machine has a roating cutting drum at the center which is fitted with cutting picks for cutting a thin layer of 100-200mm from the ground.By cutting the layers one after another,the enter coal seam thickness can be excavated,but for this it needs a long and wide exposed area of coal.Cut coal falls into boom conveyor of the machine which load the truck or small dumper at rear end of the machine or alternatively drops it on the floor to form heaps of coal. These heaps are then loaded and transported by pay loader truck combination to coal handling plant or siding.   

                                                                                                                                                     Since the machine excavated thin layers.It can be utilised to mine stone bands of the seam separately for improving the quality of coal.In India surface miners were introduced in open cast  mines of coal with this purpose,but they are now used also to extract coal from the vicinity of populated areas because it does not need any drilling blasting.                                                                                                                  Bucket wheel excavator(BWE)   :  This machine is used only in big lignite mines for extraction of shoft OB of lignite.The machine has a large rotating drum,the periphery of which has several cutting bucket that cut and get loaded with the material when the wheel moves.The filled buckets overturn with further movement of the wheel and drop this material into the chute from which the dis charge conveyor conveys it onto the system of mine belt conveyors.                                                                                                                                   Material excavated by BWE deployed in OB bench is carried by this conveyor system to the OB dump yard for spreading through spreader conveyor.Lignite excavated by BWE is carried by a separate belt conveyor system to surface lignite bunker which feeds the local power house.                                                                 Boom on which bucket is mounted can be moved up or down,and left or right as required.The boom and the discharge conveyor,each 30m long,are attached to the turntable which is mounted on a set of crawlers like a shovel.                                                                                                               One mine of Neyveli has four OB benches and one lignite bench.Each bench has a separate BWE.The machine comes in different sizes.Machine size is designed by s  Size of the bucket. 
                      

Mining Engineering

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Mining Engineering

First-aid station

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First-aid  station is a place fixed by the manger for rendering first-aid to person injured.Every first-aid station is provided with equipment as prescribed in the Third schedule of mines Rules namely: a stretcher and two blanket,Sets of splints(1.4m,0.9m,0.3m,)and sufficient tringular bandages.First-aid boxes(or cupboards),one per150 person,containin sufficient supply of large and small dressings and burn dressings,sufficient supply of sterilised cotton and adhesive plaster,roller bandages,Dettol or other antiseptic solution,a tourniquet,scissors and safety pins,soap.                                                  First aid station shall be provided at the following places On surface:-                     At pit top/incline mouth.In workshop,screening plant and    ...
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Audio visual alarm

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  When a truck or dumper backs up a person standing behind the vehicle may get crushed.To alert such a person truck/dumpers are provided with audio visual alarm.As soon as the vechile is put in reverse gear, a special horn starts blowing and the backlight flashes.It is a statutory requirements that truck,dumper or loader shall not be run unless the audio visual alarm is working.
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MINE WORKING

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  Opencast working--In open cast working,the following precautions shall be observed,namely:                                          In alluvial soil,morum,gravel,clay,debris or other similar ground-;*the side shall be sloped at an angle of sefty not exceeding 45degree from the horizontal or such other angle as the regional inspector may permit by an order in writing are subject to such conditions as he may specify therein;or the side shall be kept benched and the hight of any bench shall not exceed 1.5meter and the breadth thereof shall not be less than the height:।       Provide that the regional inspector may,be an order in writing and subject to such conditions as he may specify therein, exempt form the operation of his clause any working in the case of which special difficult exist,which in his opinion make compily with the provisions their ...
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