Pumpable cement grout
US5063967A · kind A · utility
Inventor
Key dates
| Filing date | Dec 6, 1989 |
| Grant date | Nov 12, 1991 |
| Priority date | — |
| Expiry date | Dec 6, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2111/70
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A pumpable cement grout and method for use thereof for grouting of annular cavities. There is a pumpable cement grout having portland cement, water in an amount sufficient so that the water-to-cement ratio of the grout is from about 0.6 to about 0.68 by weight, and pregenerated aqueous foam in an amount sufficient to adjust the wet density of the grout to a value of from about 55 to about 72 pounds per cubic foot. The grout is pumped into an annular cavity formed intermediate a tubular external member having a longitudinal extent and an internal member disposed in the tubular external member, so that the grout fills the cavity by flowing in a generally longitudinal direction through the tubular external member. The tubular external member may be a concrete sewer pipe, and the internal member may be a plastic liner pipe. The pressure at which the grout is injected into the annular cavity may be maintained at or below a predetermined maximum pressure, so as to avoid collapsing the plastic liner pipe.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.