Elastic agent for well cementation, preparation method thereof and elastic isolation fluid

Abstract

The invention discloses an elastic agent for well cementation, a preparation method thereof and an elastic isolation fluid, and relates to the field of petroleum drilling engineering. The elastic agent is prepared from raw materials comprising the following components, in parts by weight: 20-35 parts of bisphenol A, 10-25 parts of epichlorohydrin, 10-12 parts of diglycidyl ether, 0.1-0.3 part of sodium hydroxide, 10-20 parts of diethylenetriamine, 20-30 parts of propylene carbonate, 15-30 parts of amino polyether, 10-20 parts of dimethylimidazole, and 5-15 parts of a foaming agent. The elastic agent is not smashed under a high temperature of 150 DEG C and a pressure of 70MPa, thus when the elastic isolation fluid is introduced to the bottom of a high-temperature and high-pressure well for displacement, final effects of the elastic isolation fluid is guaranteed to not be influenced by in-advance gas releasing caused by particle smashing. The elastic isolation fluid containing the elastic agent can be used within a temperature raising range of 0 DEG C to 150 DEG C under closed environments, the applicable temperature difference range between a mudline temperature and a bottom hole temperature is wider, the elastic isolation fluid can be used for all stages of sleeve annular space, and guarantees annular space pressure increasment to be less than largest anti-collapse strength of each stage of the sleeves.

Description

technical field [0001] The invention relates to the field of petroleum drilling engineering, in particular to a cementing prefluid, specifically an elastic agent for well cementing and an elastic spacer fluid containing the elastic agent, which are used for adjusting the pressure of a trap annular space. Background technique [0002] With the gradual advancement of my country's deep-water oil and gas exploration and development strategy, some safety issues in the deep-water well testing and production process have aroused people's great attention. Because the formation fluid temperature is as high as 120°C or higher, as the formation fluid is produced, the tubing will be damaged. The temperature of the fluid in the closed annulus between the layers of the above layers of production casing, the technical casing and the surface casing will rise, and the pressure in the closed annulus of the casing will rise. In severe cases, the casing will be crushed or swelled. The pipe will t...

AI Technical Summary

Problems solved by technology

[0004] There are certain shortcomings and deficiencies in the above-mentioned elastic spacer fluid system: (1) The temperature near the seabed mud line is usually close to 4°C or even lower, while the temperature in the high-temperature section at the bottom of the well is as high as 120°C or even higher. The temperature range of the elastic spacer fluid involved is has certain limitations

At the same time, the slug position where the spacer fluid is located will receive a certain initial pressure after the wellhead is sealed, so a certain initial pressure should be given in the simulated temperature rise experiment to simulate the actual situation more realistically; (2) the elastic material involved is in the During the displacement process, before reaching the slug layer, it circulates to the bottom of the well. At this time, the pressure of the liquid column is high, and the particles are easily broken under high pressure. Since the wellhead is not closed at this time, the gas generated after the breakage cannot stay in the annular space and cannot Compensates for volume after fragmentation and therefore does not function as effective in mitigating annular pressure build-up trends

Images