| 摘要 |
<p>A cast iron pipe sleeve is provided at each end with a tight-fitting metal disk. A threaded steel rod is screwed into a nut welded in the center of the inside face of a solid disk. The disk rests against the outer edge of the sleeve and the rod extends through the interior of the sleeve and out through a hole in the center of the opposite disc and further through a hole in one of the form walls. One or more wire cables or chains secure the cuter disc to the inner edge of the pipe sleeve. Alternately, the solid disc may be centrally located within the pipe sleeve and cables secured by hooks between the solid disc and the outer edge of the pipe sleeve. A long bar or channel provided with a center hole is placed over the end of the rod and across two external studs on the form wall. As a nut is tightened onto the end of the rod against the channel, the sleeve is drawn securely and squarely against the form wall. After the other form wall is secured in place tightly against the second end of the sleeve, the concrete is poured and cured, the exterior nut is removed, the form walls are removed, and the discs and rod are removed to be reused. The sleeve remains cast in the concrete as a cylindrical passage through the thickness of the concrete for pipes. One alternate embodiment provides an interior disc bolted within the sleeve. Another embodiment provides a sleeve extending completely through the form with a bar and spacer bolted to the form ribs.</p> |
