PRACTICE OF SET PLUG TECHNOLOGY IN DEEP WELL DRILLING LINER CEMENTING

The biggest shortcoming of drilling liner cementing is to drill cement plug.As a consequence, the First Drilling Company of Liaohe oilfield, cooperated with the Drilling Research Institute of Huabei oilfield, did the research on set plug technology of liner cementing and conducted deep well field test. Then the purpose to cement liner without cement plug left was obtained. This paper introduced the improvement of extension hanger and set plug technology. It was thought that the key of cementing liner is to engage the hanger assembly outside casing, break-out and draw back easily, good plug combination and good sealing quality of seal boot. Drifting with small diameter drill pipe, weighing, measuring moment of torsion, calculating constriction distance and so on can guarantee a successful cementing job.