Based on the basic formula of the confidence interval and the sampling error of mathematical statistics, the mathematical statistics method of evaluating application effects of a new type of gas anchor was given in this paper. By the method mentioned above, the confidence interval and the sampling errors of the relevant mean value differences of Daqing Oilfield S block’s 150 wells, according to the mean value differences of the liquid producing capacity per day, the oil production per day, the submergence depth of the 10 sampling test wells, in which before and after a new type of gas anchor were laid down, were calculated. The calculation results show that a new type of gas anchor has a better effect of increasing oil production of oil well and enhancing pump efficiency. Through the real value differences analysis of the liquid producing capacity per day, the oil production per day, the submergence depth of 150 wells mentioned above, in which before and after a new type of gas anchor were laid down, it was verified. By using the confidence interval and the sampling errors of the liquid producing capacity per day, the oil production per day, the submergence depth mentioned above, in which before and after a new type of gas anchor were laid down, the application effects of a new type of gas anchor could be evaluated. And a mathematical statistics method of evaluation application effects of a new type of gas anchor is presented.
A new type of gas anchor has been more and more widely used in Daqing Oilfield, and its application effect evaluation is not only big workload, but also relating to its promotion prospects [
Assume that the sample
anchor were laid down. Two samples are mutual independence,
Assume that
Here:
The sampling error:
The sample mean values:
The sample standard deviations:
The sample variances:
The sampling error of mean value differences can be calculated with the Formula (1-3),when the confidence level of
(1) Calculate the sample mean values
(2) Calculate the value of
(3) Calculate
(4) Calculate the confidence interval of mean value differences of the liquid producing capacity per day, the oil production per day and the submergence depth, when before and after a new type of gas anchor were laid down, with the Formula (1-1) of confidence interval.
According to the basic formula and mathematical statistics method mentioned above and the production data of the oil wells, the confidence intervals and the sampling errors of the relevant mean value differences of Daqing Oilfield S block’s 150 wells, with the mean value differences of the liquid producing capacity per day, the oil production per day, the submergence depth of the 10 sampling test wells, in which before and after a new type of gas anchor were laid down, are calculated, when the confidence level of 95.0% is set. The confidence intervals and the sampling errors are: [−54.1860, −16.5640], [−2.0692, −0.0188], [12.6554, 245.9846]; ±18.8111 t/d, ±1.0252 t/d, ±116.6646 m, which show that the liquid producing capacity per day increases, the oil production per day increases, the submergence depth reduces. It is indicated that a new type of gas anchor has a better effect for increasing the production of oil well and enhancing the efficiency of pump.
Through the comparisons and analyses of the real measurement data from oil wells, the well numbers of the real value difference of the oil production per day, the oil production per day and the submergence depth, being within the confidence intervals mentioned above, of Daqing Oilfield S block’s 150 wells, in which before and after a new type of gas anchor were laid down, are 142,146 and 145 respectively, with all achieving the confidence level of 95.0%,which means that the mathematical statistics method to evaluate the application effects of a new type of gas anchor given by this paper is feasible.
(1) Based on the basic formula of the confidence interval and the sampling error of mathematical statistics, the mathematical statistics method of evaluating application effects of a new type of gas anchor was given.
(2) According to the method mentioned above, the confidence intervals and the sampling errors of the relevant mean value differences of Daqing Oilfield S block’s 150 wells, with the mean value differences of the liquid producing capacity per day, the oil production per day, the submergence depth of the 10 sampling test wells, in which before and after a new type of gas anchor were laid down, were calculated when the confidence level of 95.0% is set. The calculation results show that the liquid producing capacity per day increases, the oil production per day increases and the submergence depth reduces when after a new type of gas anchor were laid, which means that a new type of gas anchor has a better effect for increasing the production of oil well and enhancing the efficiency of pump.
(3) Through the comparisons and analyses of the real measurement data from oil wells, the well numbers of the real value difference of the oil production per day, the oil production per day and the submergence depth being within the confidence intervals mentioned above of Daqing Oilfield S block’s 150 wells in which before and after a new type of gas anchor were laid down are 142, 146 and 145 respectively with all achieving the confidence level of 95.0%, which means that the mathematical statistics method to evaluate the application effects of a new type of gas anchor given by this paper is feasible.
JunWang,Wen-HeLi,RongZhong, (2015) Mathematical Statistics Method of Evaluating Application Effects of a New Type of Gas Anchor. Energy and Power Engineering,07,319-322. doi: 10.4236/epe.2015.77029