Drilling has been on going at Menengai high temperature field since 2011. The wells are regular well design wells with the 20 inch surface casing set at 60-70m. 13⅜ inch anchor casing set at 400m depth and the 9⅝ inch production casing set at between 800-1400m. The wells are targeted to be drilled to a total depth of 2500-3000m, with the slotted 7 inch liners run to the bottom. All the casings used are grade K55. Data from offset wells drilled earlier have helped design the depth of the production casing to avoid cold inflows into the wells. Wells located at the center of the field which is at a higher elevation have the production casings set at about 850m, while wells sited further away, the production casing has been designed to be set further deeper, to up to 1400m. With a good number of wells at the Menengai field having the production casing being set at 1400m, this paper looks at design of 9⅝ inch K55 production casing, slurry design, the most effective cementing method for cementing the casing to ensure an effective cement job. Cementing methods that will be discussed include cementing with cementing head and plugs, two stage cementing, cementing with C-Flex RPL from peak using the inner string method, reverse circulation cementing with inner string and flap gate valve collar and use of foam cementing. The paper looks at a number of wells which have already been completed being drilled. Pressure and temperature logs of the wells are analyzed with the borehole geology of the wells to identify the cold inflow zones in the wells already drilled and remedial mechanisms available for sealing off the cold zones in completed wells and which could be the most effective method to be applied at the Menengai field. The methods include use of External casing packer (ECP), tie back design and running a cemented liner.

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