The basic function of casing is to protect the borehole and the drilling tools against caving in weak overburden material or dykes and to prevent excessive water losses or inflow.
Our standardized casings (BW, NW, HW, HWT, PW and PWT) are hollow tubes from high quality steel either flush-jointed or flush coupled.
Flush –jointed casing has male and female threads and no coupling is used.
Flush – coupled casing is joined with a coupling of the same outside diameters as the casing itself. The inside diameter of the coupling is the same as that of flush-joint casing,
Flush – coupled casing has a thinned wall than just Flush –jointed casing type but the outside diameter of both types is the same.
Standard geometric data is based on published industry values as described under the International Standard for ISO 10097-2. Some of the recorded values are calculated by Kobald’s Mining Services Ltd’s supplier. The care and handling, as well as drilling conditions, practices and equipment used, will also play a significant role in the ultimate capacity and performance.