Abstract: It is important for accurate prediction of bottom-hole circulating temperature (BHCT) to be got in drilling, completion and cement slurry design. In this paper, it was compared the downhole circulating temperature of API abroad with the actual testing data at home. The results show that the mean relative
error exceeds 5 percentage of the conventional predicting temperature, the temperature can be evaluated with different empirical coefficients under arbitrary depth of well, and at any circulating time. Although the method is simple, it can not satisfy the requirement for the drilling and cementing construction. In order to obtain the exact temperature distribution, the researchers should be further to test the downhole circulating temperature, at the same time, to simulate the heat transfer process by computer.

Key words: API method, cementing, circulating temperature, shut-in temperature