SU1555471A1 - Method of determining the amount of slime in borehole - Google Patents

Abstract

The invention relates to the drilling of deep oil and gas wells. The goal is to simplify the way. The pressure in the injection line is measured during the descent and periodic lifting of the drilling tool from the bottom during the flushing, development or drilling of the well. By the invariance or increase in pressure during periodic lifting of the drilling tool, the wellness of the wellbore is judged. 2 Il.

Description

one

(21) 4423441 / 23-03

(22) 05/10/88

(46) 04/07/90. Bul № 13

(71) North Caucasus State Research and Design Institute

(72) V.A. Khurshudov, N, I0Andrianov, and Z.N. Bocharova

(53) 622024 (088.8)

(56) Patent CD1A No. 4495803,

.cl. E 21 B 47/00, published 01/29/85,

Gabuniy G.V. Some issues of cleaning the wellbore from cuttings with flushing fluid. .Azerbaijani oil industry, 1964, no. 4, p. 20-23.

(54) METHOD FOR DETERMINING WELL-BORED WELLS

. (57) The invention relates to the drilling of deep oil and gas wells. The goal is to simplify the way. Iamer pressure in the injection line during the descent and periodic lifting of the drilling tool from the bottom in the process of washing, working out or drilling a well. By the invariance or increase in pressure during periodic lifting of the drilling tool, the wellness of the wellbore is judged. 2 Il.

The invention relates to the field of drilling deep oil and gas wells, in particular to methods for controlling the elapticity of wellbores drilling in unstable rocks.

The purpose of the invention is to simplify the method.

Figures 1 and 2 are diagrams of the injection pressure of the drilling fluid into the well as the drilling tool is raised from the bottom of the well.

The method is carried out as follows.

When the drilling tool is lowered into the well, drilling or drilling of the wellbore is carried out in a rotary manner with flushing of the drilling fluid at a constant supply of drilling pumps. Stop the rotor and measure the pressure in the discharge line.

The drilling tool is cut off from the bottom at a speed of no more than 0.5 m / s at a height of 5-N) m with pressure measurement in the discharge line. The drilling tool is lowered to the bottomhole at a speed of 0.3-054 m / s with pressure measurement in the injection line. From the change in pressure in the injection line, it is concluded that the wellbore is sludge. The operation is repeated 2-4 times per hour.

PR and er. The method was tested on the well during drilling and development in the range of 3270-4610 m, folded by deposits of the upper Maikop,

Fig. 1 shows a fragment of the injection pressure diagram of the drilling fluid in the well during the development of the interval 3343-3352 with "The development was carried out in a rotary manner using the following drilling

tools: a chisel with a diameter of 295.3 mm, augmented drill pipes with a diameter of 229 mm, a length of 62 m, drill pipes with a diameter of 140 mm. The parameters of the development mode: load on the bit - up to 50 kN, rotor speed - 80 rpm, pumping flow rate - 33 pho3 sm / s, drilling fluid injection pressure - 9.2 MPa, processing speed - 12 m / h,

The parameters of the drilling mud are: density — 2200 kg / me, viscosity –– 30 s, filtration rate — 5.2 cm3 / 30 min, static shear stress after 1/10 min — 3 / 7.5 Pa. The pressure in the discharge line was recorded by means of a self-recording manometer with a recording of the pressure chart in the discharge line on a paper tape. On the x axis, time was recorded on a scale of 1 mm / min. The pressure in the injection line on a scale of 1 MPa / 6 mm was recorded along the Y axis.

After the rotor stopped, the pressure in the injection line was measured, which was 9.2 MPa - point A. The drill tool was removed from the bottom at a speed of 0.5 m / s to the Yume height by measuring the pressure in the discharge line. In this case (Fig. 1, the pressure in the injection line increased to 9.5 MPa - point B. Then the drilling tool was lowered to the bottomhole at a speed of 0.4 m / s with pressure measurement in the discharge line, which decreased to 9 MPa - point C Measurements were made at. Subsequent tearing of the drilling tool from the bottom was also accompanied by an increase in pressure in the injection line: in 5 No. from 9 MPa - point D to 10.5 MPa - point Ej in 5i5 from 9 MPa point G to 9.5 MPa - point Н; in 540 с 9 MPa - point b. Up to 10 MPa - point M. When the drilling tool is lowered to the bottom, the pressure in the load taline line decreased to 9 MPa - points F, K, N. Based on the increase in pressure

about

five

laziness in the injection line during lifting of the drilling tool from the bottom in the process of working out, it was concluded that the wellbore was slammed, which was confirmed by the subsequent blockage of the annular space of the wellbore accumulated in it, which led to an increase in pressure in the injection line to 15.5 MPa - point Q, termination of the drilling fluid circulation and loss of mobility of the drilling tool. For comparison, Fig. 2 shows the pressure chart in the injection line recorded during the development of the interval 3315-3320 m. The time on a scale of 1 mm / min was recorded along the X axis. The pressure in the injection line on a scale of 1 MPa / 6 mm was recorded along the Y axis. The parameters of the development mode and the drilling fluid are the same. In this case, the rises of the boring tool were accompanied by a regular decrease in pressure in the injection line from 10.5 MPa - point R to 10 MPa - point S due to the development of negative hydrodynamic pressures in the annular space of the wellbore, which indicates the absence of sludgeiness of the wellbore.

Claims (1)

Invention Formula A method for determining the sludgeiness of a wellbore, which includes measuring the pressure in the injection line during the descent of the drilling tool during the flushing or drilling of the wellbore, characterized in that, in order to simplify the method, the pressure in the injection line is measured when the drilling tool periodically rises from the bottom, and the sludgeiness of the wellbore is judged by the pressure change during periodic lifting of the drilling tool.