Patent ID: 8567871
Filing Date: 2013-10-29
Classification: E21C,E21D

Abstract:
1. A method for automatically producing a defined face opening in a longwall mining operation in underground coal mining, including the steps of: providing a face conveyor; providing at least one extraction machine; providing respective hydraulic shield support frames that include, as main components, a floor skid arrangement, a gob shield, a top canopy, and support connection rods; disposing inclination sensors on at least three of the group consisting of said floor skid arrangement, said gob shield, said support connection rods, and a gob-side region of said top canopy; ascertaining from said inclination sensors an inclination of those components of said shield support frames provided with said inclination sensors relative to a horizontal; in a computer, calculating from the ascertained inclination data, by a comparison with base data stored in the computer, and which base data defines a geometrical orientation of said shield support frame components as well as a movement thereof during a stepping process, a respective shield height of said shield support frames perpendicular to a bed of said shield support frames; disposing further sensors on said at least one extraction machine; acquiring from said further sensors a cutting height of said at least one extraction machine as a face opening; storing corresponding data sets for each section of a longwall mining operation that an associated one of said shield support frames passes through; and in terms of a location-synchronous analysis on a section of the longwall mining operation, comparing, for possible adjustment purposes, said cutting height of said at least one extraction machine with said shield height of said shield support frame when said shield support frame, which trails said at least one extraction machine with a time delay, has reached the position to which relates that cutting height of said at least one extraction machine which was used in the last-mentioned comparing of said cutting height with said shield height.