Research on precision design of sand control on high yield offshore gas field

Advanced high quality screen sand control is a commonly used sand control technology for high yield offshore gas field, and the rationality of sand control precision design directly affects sand control effect. Currently, Because the sand standards of this kind gas field is rare, the most popular design method of sand control precision is the Saucier’s D50=（5~6）d50 method which was proposed in the 1970s. And this method wasn’t suitable to some special formation due to simple consideration factors. This paper puts out an effective sand control standard which fits the offshore gas field perfect. Taking the actual formation cores in LiuHua 19-5 gas field as example, the experiment of testing the effect of sand uniformity coefficient on sand controlling precision design was conducted, and the results showed that a higher uniformity coefficient may cause a lower accuracy of sand control. For the first time the effect of sand clay content on the precision were studied, and another conclusion comes that the higher the clay content the greater the precision value and this phenomenon can be ignored if the clay content is not that high. We also found that the advanced high quality screen sand control should not be used if the clay content is higher than 14%. 8 × 8 set of sand simulation results follow D50=（3~5）d50, which is different from the traditional method put forward by Saucier, and prove that the method of fine sand control is reasonable for sandstone gas field. All these conclusions can provide basis for sand control precision design in sandstone gas field and sand control scheme optimization.