| 摘要 |
<p>The injector has an opening(4) through which the grout is forced by manual depression of a plunger. The opening can be closed at the termination of the injection phase to obviate a reversal of grout flow at the mouth of the hole. The head of the injector may be covered by two parallel plates (12, 13), each with an offset opening, and forming a simple slide valve. The external plate(12) may be rotated to effect the coincidence of the openings or vice versa. The outer plate(13) may have an axially projecting nose(9) with a radial projection(10). The nose(9) engages a matching recess (11) in the anchor unit(7) to positively locate the injector at the start of the operation.</p> |
