Research On Fully Mechanized Mining Technology In Steep And Soft Seam

The first mining face in the second well of Sichuan Liziya south second coal is inclinedmedium-thickness seam with an average dip of48o, a maximum of57°, thickness of2.4m.And the seam and roof is soft. The production efficiency is low and working condition isunsafe because of the backward original mining technology so that it is very important forsafe and effective mining to study the comprehensive mechanization in the inclined soft seam.According to the geological condition of the first mining face in the south second well,optimization of supporting research and equipment selection have been conducted in inclinedfully mechanized mining “three machines” and according to arts demand, new functionalrequirements to the equipments have been put forward. The endless rope cables are designedfor the inclined fully mechanized special shearer and a new fault forced braking device isadded, and walking wheel pitch and modulus are enforced so traction force is strengthened.The hydraulic support has feature of active-skid and auto shift characteristic. The face conveyor is equipped secondary mechanical anti-skid, large pitch pin discharge device and so on.The “three machines” can be used with a dip of60°. The open-off cut in the working face isarranged with true dip and down construction method, and raise-boring machine is used tolarge diameter borehole. The problem of lifting coal-gangue in the down construction methodhas been solved. The adoption of horizontal transportation and installation of hydraulicsupport and two independent transports with chutes and supports has improved installationprogress greatly. Adopting “the integrated method” and “down-up movement” to avoidskidding and falling and using “two closed, two isolation” to prevent the fly waste so thestability of working face equipment and safety of workers are guaranteed.The complete set of technology of fully mechanized mining in steep soft coal seam is successful in steep soft coal face the south second well with the highest monthlyproduction of up to32000T. There was no serious safety accidents comparing with thetraditional steeply inclined seam mining method, greatly improving the production efficiency,ensure safety in production, and has achieved remarkable economic and social benefits.