A high temperature resistant cementing cement slurry system

Abstract

The invention discloses a high temperature resistant well cementing cement slurry system, and relates to the technical field of cement slurry systems. The invention includes the following components: Portland cement: 60-75%; anti-strength decay agent: 15-25%; crystal form stabilizer: 2-8%; high-temperature retarder: 0.5-6%; Water agent: 3‑8%; the Portland cement is one of grade D oil well cement or low heat cement, with a specific surface area of ​​280‑350m 2 / kg; SiO in the anti-strength decay agent 2 Content > 90%, mesh number ≥ 150 mesh; SiO in the crystal form stabilizer 2 Content > 30%, mesh ≥ 600 mesh. In the present application, by adding a crystal form stabilizer, when the cement will be hydrated, it will participate in the hydration reaction, and the metal ions will enter the structure of calcium silicate hydrate to prevent the tobermorite in the hydration product from turning to xonotlite. transformation, so that the cement stone maintains a dense structure, so it has good high temperature stability.

Description

technical field [0001] The invention relates to the technical field of cement slurry system, and more specifically relates to a high-temperature well cementing cement slurry system. Background technique [0002] With the development of deep oil and gas resources in my country, the number of deep wells and ultra-deep wells is increasing year by year. Due to the geological structure, the temperature in the well increases with the depth of the well. In some western regions, the static temperature in the well has reached 230°C. The high temperature environment puts forward severe adjustments to the drilling and completion engineering. The development of a new high temperature cementing slurry system is of great significance to the development of deep oil and gas resources in my country. [0003] At present, high-temperature cementing cements face many problems. Most high-temperature retarders are prone to failure when the temperature is higher than 170°C, and it is difficult t...

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Problems solved by technology

[0006] In order to overcome the defects and deficiencies in the above-mentioned prior art, the present invention provides a high temperature resistant cementing cement slurry system. The hydration product of cement changes from tobermorite to xonotlite. In this application, by adding a crystal form stabilizer, it participates in the hydration reaction when the cement is hydrated, and metal ions enter the structure of calcium silicate hydrate , to prevent the transformation of tobermorite to xonotlite in the hydration product, so that the cement stone maintains a compact structure, thus having good high temperature stability

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