Shearing cross-linking sensitive plugging agent and preparation method thereof

Abstract

The invention provides a shearing cross-linking sensitive plugging agent used for the drilling engineering. The plugging agent comprises the following components: 40 to 60 parts of organic titanium coal-oil solution, 40 to 60 parts of modified guar gum solution and 2 to 5 parts of emulsifier, wherein the organic titanium coal-oil solution is the mixture of coal oil and organic titanium, the organic titanium is any one of the titanate compounds, the modified guar gum solution is obtained by the graft copolymerization of acrylamide, hydroxymethyl acrylamide monomer and guar gum, and the emulsifier is fatty acid polyoxyethylene ether. The preparation method comprises the following steps: the 2 to 5 parts of the emulsifier is added to the 40 to 60 parts of the organic titanium coal-oil solution, the emulsifier and the organic titanium coal-oil solution are evenly stirred, then the 40 to 60 parts of the modified guar gum solution is added into the mixture slowly and stirred for 1 hour at the temperature of 30 to 35 DEG C to form stable reversed emulsion through a colloid mill, and the finished product of the shearing cross-linking sensitive plugging agent is further obtained. The shearing cross-linking sensitive plugging agent is used for plugging a drilling, the cross-linking agent can be immediately mixed with macromolecule under the action of the high shearing rate of the bit port to generate cross-linking, and the gelling stemming similar to the plastic solid is formed so as to rapidly block the serious leakage layer.

Description

technical field [0001] The invention relates to the field of drilling plugging engineering, in particular to a shear cross-linking sensitive plugging agent and a preparation method. Background technique [0002] Lost circulation is a common and serious problem in oilfield drilling, which not only affects the drilling speed, but also causes huge economic losses. At present, the plugging method commonly used at home and abroad is mainly bridge plugging, because it is difficult to accurately judge the properties of the leaking layer (such as the width of the fracture) in the downhole, and the particle size of the plugging agent does not match the width of the fracture in the leaking layer, which often leads to poor plugging effect. Repeated leaks occurred after Jiahe plugged the leak. At the same time, bridge plugging needs to be tripped during the implementation of plugging, which affects the efficiency of drilling operations. In recent years, from the research and applicati...

AI Technical Summary

Problems solved by technology

[0002] Lost circulation is a common and serious problem in oilfield drilling, which not only affects the drilling speed, but also causes huge economic losses

At present, the plugging method commonly used at home and abroad is mainly bridge plugging, because it is difficult to accurately judge the properties of the downhole leaking zone (such as the width of the fracture), and the particle size of the plugging agent does not match the width of the crack in the leaking zone, which often leads to poor plugging effect. Repeated loss after Jiahe plugging

At the same time, bridge plugging needs to be tripped during the implementation of plugging, which affects the efficiency of drilling operations