Study and application of high temperature retarder GH-9 for cement slurry.

In order to solve cementing problems in deep and ultra-deep wells, and to avoid deficiencies of conventional retarders for cement slurry such as over delayed and sensitive, high temperature retarder GH-9 for cement slurry was developed. As a copolymer made from itaconic acid and AMPS, it exhibits excellent delayed coagulation and good compatibility with other additives such as dispersants and fluid loss reducers. What is more, the slurry with GH-9 in has very short transient time in thickening test. Field experience showed the high temperature retarder GH-9 for cement slurry met requirements of cementing job at high temperature.