For cased boreholes, LEFFER offers double-walled casings in different of useful lengths. Our low manufacturing tolerance for diameter, roundness and straightness pays off on the construction site: Precisely fitting casing joints ensure fast, straight placement, bolting and optimum force transmission. The casing joints, consisting of a female and male part, are secured with radially arranged conical bolts. The inside and outside of the casings are smooth throughout their entire length, which prevents the reinforcement cage or drilling tool from getting stuck when pulling the casing.
LEFFER casings have also proven themselves many times over in cased kelly drilling through water-bearing soil layers or in drilling with water ballast. To prevent water and fines from entering the casing, both the cone bolts and the casing joints can be sealed with additional sealing rings.