Abstract
Cement manufacturers in the Appalachian and Michigan Basins stopped making API Class A cement years ago. Today, the pumping service industry provides its customers with Type I cement manufactured to ASTM C150-97 specifications. Many operators in these producing basins are unaware of this change and its implications for a quality cement job.
Much has been written about the characterization of Class H and other oilwell cements. For example, Polkowski concluded that the cement thickening time is directly related to Blaine Fineness and the average size of the C3S crystals and fluid loss control is a function of particle size distribution.1 Nelson traced the variability in oilwell cement back to the production plant, stating portland cement behavior can be linked to several production parameters including kiln temperature, raw materials processing and grinding. 2
It is the intent of this paper to educate the reader about the characteristics of ASTM C150-97 Type I cement being pumped in the Appalachian and Michigan Basins today. Cement from six different cement plants was analyzed using cement microscopy and chemical analysis. Typical cement laboratory tests were run to get a comparison of thickening time, compressive strength development and rheology using normal water/cement ratios.