It has become a high priority task of the drilling engineer to be closely involved in all aspects of the cement job design for a horizontal Marcellus well. Close cooperation with the cementing service company is required. It should be common place to use a simulator to facilitate job design and predict situations which could result in job failure. Comparing simulator runs to real time monitoring of job parameters can give indications of down-hole problems. Making on the spot decisions to change the job design can sometimes lessen or prevent the negative impact on the job performance which would have resulted if no changes were implemented.
This paper will review the accepted industry standards for hole conditioning, pipe centralization, pipe movement and slurry designs for HZ wellbores. A chart will be presented that includes all the tasks required for job design. Illustrations are provided to give operators realistic expectations of the engineering support they should be getting from their cementing service companies. Several slurry designs being used in Appalachia are presented and the required properties needed for successful horizontal well cementing in Appalachia. Results of these slurry designs will be presented as a relationship to the breakdown and treating pressures during the subsequent hydraulic fracturing treatments. The issue of the prevention of backside gas pressure will be discussed.