Patent ID: 8100607
Filing Date: 2012-01-24
Classification: E21D

Abstract:
1. A rock anchor which includes: an elongate, hydraulically inflatable anchor tube made of a ductile material and defining a closed leading end, a trailing end, and a tube cavity extending between the ends; an end cap on a trailing end of the tube, defining a feed aperture in communication with the tube cavity for pressure feeding a liquid substance into the tube cavity for inflating the tube; pressure indicator means, carried by the end cap, configured for indicating when, as a result of pressure feeding of a liquid substance into the tube cavity, a predetermined installation pressure is reached in the tube cavity; and a non-return closure for the feed aperture, and in which: the pressure indicator means includes: the end cap includes: the feed aperture is defined through the ferrule; the end wall defines therethrough an indicator formation aperture for the indicator formation a portion of the ferrule, extending from the second end of the ferrule and past the feed aperture, defines a round cylindrical outer surface permitting snug sliding entry of said portion into a round entry of a collar-like coupling of a high pressure water hose.