SU1744242A1 - Fluid for releasing stick pipes in hole - Google Patents

Abstract

Fluid for releasing drill and casing strings stuck in the well, containing oil in the ratio of 5-95% and waste of glycerol production at the final stage of 5-95%, previously diluted with water to a density of 1270-1300 kg / m3. 2 tab.

Description

The invention relates to the drilling of oil and gas wells and can be used in the release of stuck drilling and casing in conditions of high differences and temperatures.

A known fluid for releasing drill pipes stuck in the well, including oil with additives of a surfactant, for example, sulfonol OP-10.

The disadvantage of a liquid is its low efficiency in practice. In addition, the preparation of a mixture of oil with sulphonol causes a number of difficulties, especially under marine conditions, from the point of view of environmental pollution.

Fluid is also known to release drill pipes stuck in the borehole, which includes a mixture of oil and caustic soda.

The disadvantage of oil-alkaline baths is that these fluids have little effect on the thermodynamic electrode potential of the metal of the drill pipe and, consequently, on the separation of the contacting surfaces - the strings from the borehole wall. In addition, when oil is mixed with an aqueous solution of sodium hydroxide, the system turns out to be heterogeneous: separation of components occurs, which reduces the efficiency of the bath. The high alkalinity of this bath contaminates the drilling fluid, and the completeness of the displacement of the drilling fluid from the sticking zone deteriorates.

The aim of the invention is to increase the efficiency of the release of the pipe string in the well by increasing the thermodynamic electrode potential of the metal of the pipe string and reducing the separation force.

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-N 4 Yu

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YU

This goal is achieved by the fact that the liquid for the release of a string of pipes stuck in the well, containing oil as an alkaline additive, contains waste products of glycerin production at the final stage in the following ratio of ingredients, wt.%:

Oil 5-95

Production waste

glycerol at the final stage5-95

The waste of glycerin production at the final stage, previously diluted with water to a density of 1270-1300 kg / m3, has the following composition: polyglycerol at least 27%; caustic sodium not more than 8%; sodium chloride not more than 8%; water the rest.

To evaluate the effectiveness (E) of the proposed and known liquids, the experiments were carried out under identical conditions (Table 1).

Metallic samples of steel St.40 (strength D) - a silver-silver electrode were used as indicator electrodes. To obtain comparable values, the measurement results were recalculated using a hydrogen electrode, generally accepted as zero.

The high adsorption of alcohol by clay and the high alkalinity of the waste (pH 12.7–13.3) lead to a decrease in the mechanical force due to adhesion forces and frictional parameters of the contacting surfaces. These properties were evaluated by determining the peel strength of a stuck pipe sample (in the form of a disk) from a mudcake before and after exposure to known and proposed formulations (see, Table 2). The experiments were carried out according to the well-known method.

As the drilling mud, the treated solution was used with USS from hydromica clay (as the most dangerous type of drilling fluid with respect to sticking). The composition of the solution: hydromica clay + UShR + water. Indicators:

р 1270 kg / m3; with; F 25 cm3; SNA 35/56 dPa, pH 10.

Another positive indicator of the recommended composition is its high density, p 1270-1300 kg / m3, which will reduce the likelihood of annular discharge during the installation of the bath. Use the proposed fluid to release stuck in the well.

pipe columns provide an increase in the efficiency of the release of the pipe column, prevents environmental pollution, especially in water basins, reduces the likelihood of release during

installation of the bath, which leads to increased performance, reduces their productive calendar time.

The economic effect is determined by the reduction of funds and time to eliminate sticking. The cost of the proposed liquid is not more than 40 rubles / ton. The waste of glycerol production is sufficient,

Claims (1)

Invention Formula Fluid to release strings of pipes stuck in the well, including oil and alkaline additive, characterized in that. in order to increase the release efficiency by increasing the absolute value of the thermodynamic electrode potential of the metal of the pipe string and reduction of the separation force, as an alkaline additive, it contains the waste of glycerol production for the final flocks, previously diluted with water to a density of 1270-1300 kg / m, in the following ratio of ingredients, wt.%: Oil Waste from the production of glycerin at the final stage, previously diluted with water to a density of 1270-1300 kg / m3 5-95 5-95 Table 1 table 2 Time exposure 3.5 hours