Medium high temperature early strength agent for oil well cement

Abstract

The invention discloses a medium high temperature early strength agent for oil well cement. The medium high temperature early strength agent for the oil well cement comprises the following components in part by weight: 1.2 to 2.8 parts of sodium thiosulfate, 0.2 to 2 parts of basic aluminum chloride, 0.2 to 0.6 part of sodium nitrate, 0.2 to 1 part of microsilicon and 0 to 0.2 part of calcium aluminate. The medium high temperature early strength agent for the oil well cement has the beneficial effects that: the early strength of cement stone can be improved obviously at high temperature on the premise of not influencing the thickening time; the problem that the early strength of the cement stone is developed slowly at medium high temperature is solved; the medium high temperature early strength agent has high compatibility with other additives; and at medium temperature, water loss of cement paste can be controlled, the adding amount of a fluid loss agent is reduced, and the cost is saved.

Description

technical field [0001] The invention relates to the technical field of early-strength agents for oil well cement, in particular to a medium-temperature early-strength agent for oil well cement. Background technique [0002] With the deepening of oil and gas exploration and development, there are more and more wells with long sealing and large temperature difference. Most of these wells use one-time cementing, and the construction time is long, which requires the cement slurry to have long thickening time and high top strength. . The thickening time of cement slurry determines the amount of retarder added, and the addition of most retarders will naturally affect the development of top strength. [0003] Commonly used early strength agents include inorganic salts and organic compounds. Among inorganic salts, chloride is the most commonly used early strength agent for oil well cement. Others such as carbonates, silicates, aluminates, thiosulfates and sodium The hydroxides of ...

AI Technical Summary

Problems solved by technology

[0007] 1. Various raw materials, long production time and low efficiency;

[0008] 2. The applicable temperature is low, mainly for shallow wells and surface low-temperature cementing;

[0009] 3. High temperature has obvious influence on thickening time;

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