Patent ID: 8740504

Claim:
An apparatus for retensioning a loose roof plate held by a roof bolt, comprising: a main spacer for occupying a space between a head of the roof bolt and the loose roof plate, the main spacer having a threaded circumferential outer surface and a radially extending slot for inserting a shaft of the roof bolt therein; a washer for occupying a space between the main spacer and the loose roof plate, the washer having a radially extending slot for inserting the shaft of the roof bolt therein; and a nut having a threaded hole for passing the head of the roof bolt therethrough, for threading onto the threaded spacer and for tightening onto the threaded spacer until the roof plate is firmly pressed against the roof, wherein rotation of the main spacer relative to the washer is limited by a tab extending from one of the main spacer and the washer into a recess in the other of the main spacer and the washer.