Abstract: Grouting equipment and methods suitable for use in underground water wells, which accomplish their goals by better centering the grouting equipment within a bore hole, even in curved bore holes, in an manner that prevents leakage of the grout into the well. Improved grouting is achieved by using corrugated, bendable incasings and expandable tubes which create a seal between the incasing and the well wall for the grout, and which prevent both contaminated surface water and grout from contaminating the groundwater. The disclosed techniques are implementable in such a manner that grouting does not necessarily need to precede the location of a groundwater nappe.