Edward G Humphreys

US Patent:

51941937, Mar 16, 1993

Filed:

Apr 16, 1992

Appl. No.:

7/869763

Inventors:

Edward G. Humphreys - Cordova TN
Robert D. Rice - Germantown TN

International Classification:

B22D 1910
B29B 1700
B32B 3500
E04B 116

US Classification:

264 35

Abstract:

This method for the trenchless, in situ repair of underground pipe includes the steps of isolating a section of pipe to be repaired, heating a sealing material (having predetermined physical and chemical properties) to a liquid state, pumping the liquid material, under pressure as required, into the isolated section of pipe; circulating the liquid through the isolated section of pipe; and forcing the liquid into and through cracks in the pipe and into the soil surrounding the pipe. This is a thermal process wherein the molten material which is forced into the cracks and soil, cools and solidifies. The remaining liquid circulates through the isolated section of pipe and stays in a liquid state, because of retained internal heat, until it is removed from the pipe for storage and reuse. With this process, a novel bottom plug is used which allows the sealant to be applied to all cracks, crevices and even openings found where the smaller pipe connects to the larger pipe. If water is present within the system being repaired, a bottom plug allows it to accumulate and be drained so as not to interfere with the sealing process.