Patent ID: 7927043
Filing Date: 2011-04-19
Classification: E21D

Abstract:
1. A steel pipe rockbolt, comprising a rockbolt main body and a pressurized-fluid-introducing sleeve fixed by welding to the rockbolt main body at an end for introduction of a pressurized fluid, wherein the rockbolt main body is a deformed pipe having an expansive groove extending along an axial direction of the deformed pipe, and wherein the rockbolt main body is configured to hydraulically expand upon the introduction of the pressurized fluid, the pressurized-fluid-introducing sleeve comprising a projecting part with an outer diameter larger than a diameter of an aperture of a bearing plate and a pressurized-fluid-introducing hole, and a bearing-plate-holding part with an outer diameter smaller than the diameter of the aperture of the bearing plate, the projecting part and the bearing-plate-holding part defining a passageway, a portion of the expansive groove of the rockbolt main body being positioned within the passageway, whereby the bearing plate is held in contact with a step between the projecting part and the bearing-plate-holding part, the projecting part and the bearing-plate-holding part having a single, one-piece unitary construction, the projecting part being fixed relative to the bearing-plate-holding part, whereby the bearing plate locates on an edge of a rockbolt-setting hole drilled in a bedrock or ground, and the bearing-plate-holding part extends through the aperture of the bearing plate into the rockbolt-setting hole, the projecting part and the bearing-plate-holding part being substantially rigid, the rockbolt main body configured to hydraulically expand relative to the projecting part and the bearing-plate-holding part to secure the rockbolt main body within the rockbolt-setting hole.