| 摘要 |
A plug to be located in a drilled hole to accept the tip of a bolt or rod comprises a hollow cylindrical body closed at one end and having 2-16, pref. 6-8 ribs radiating from the closed end. For providing anchorage points or locating explosive charges. The end may be flat or convex. The body may also feature narrow circumferential ribs. Claims plugs made of polyethylene, polypropylene or similar materials. Unlike solid epoxy, polyethylene or polyurethane resin plugs cast in situ, the radial ribs of the moulded plug provide some clearance between the plug and the walls of the drilled hole, to relieve any trapped gas or water pressure which otherwise would tend to eject the plug. |
