Abstract In the mining of a substantially horizontal bed of trona, stronger than the overlying and underlying strata, the method of driving substantially parallel entries into the trona formation, connecting said entries by at least one primary passage thereby defining the main trona pillar to be mined, supporting the roof of a primary passage by means of a movable roof supporting structure and mining the exposed face of the trona pillar under the protection of the roof supporting structure, removing the mined material and advancing the supporting structure so that it remains essentially adjacent and parallel to the mine face as it recedes, continuously advancing the roof supporting structure to incremently effect caving of the previously supported roof and continuing the mining of the exposed face of the trona pillar under the protection of the roof supporting structure, removing the mined material and advancing the supporting structure so that it remains essentially adjacent and parallel to the mined face as it recedes.
Inventors
👤 J Pennington
👤 E Gardiner
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-05 23:09
CPC Classifications
E; E21; E21C; E21C41/00; E21C41/16; E21C41/20
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
138 words
A method of mining subsurface deposits of trona which comprises: a. driving substantially parallel entries into a trona formation and connecting said entries by at least one primary passage thereby defining the main trona panel to be mined; b. supporting the roof of the primary passage by means of movable roof supporting structures; c. mining the exposed longwall face of the trona panel under the protection of the roof supporting structures, said longwall face being substantially parallel to the facture pattern of the trona; d. removing the mined trona; e. advancing the supporting structures so that the support remains substantially adjacent and parallel to the mined face as it recedes; f. incrementally caving the previously supported roof; and g. advancing the supporting structures as the mining proceeds sufficiently to effect spontaneous incremental caving of the previously supported roof.
Claim 2
Independent Claim
138 words
A method of mining subsurface deposits of trona which comprises: a. driving substantially parallel entries into a trona formation and connecting said entries by at least one primary passage thereby defining the main trona panel to be mined; b. supporting the roof of the primary passage by means of movable roof supporting structures; c. mining the exposed longwall face of the trona panel under the protection of the roof supporting structures, said longwall face being substantially parallel to the facture pattern of the trona; d. removing the mined trona; e. advancing the supporting structures so that the support remains substantially adjacent and parallel to the mined face as it recedes; f. incrementally caving the previously supported roof; and g. advancing the supporting structures as the mining proceeds sufficiently to effect spontaneous incremental caving of the previously supported roof.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein incremental caving is effected before no more than 18 feet of unsupported roof is exposed by the movement of the supporting chocks.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein trona is removed from the roof in an amount sufficient to weaken the structure, to induce incremental spontaneous caving.