SU1579979A1 - Borehole drilling device - Google Patents

Abstract

The invention relates to a drilling technique. The goal is to expand the field of application and increase reliability by eliminating the stitching of a drill rod by products of destruction. A gaseous blowing agent is fed into the pipes of the drilling rod. The pressure of the agent is controlled by varying the hydraulic resistance by introducing a counter flow of gas, liquid, or a mixture of them, which is injected in the form of jets into the annular space towards the outlet reverse flow of the blowing agent. In order to increase the pressure of the purge agent in the well by increasing the resistance to movement of the combined stream formed after mixing the purge agent with the counter-stream containing fluid, by increasing the viscosity, foaming agents can be added to the latter. 3 hp f-ly, 1 ill.

Description

The invention relates to a technique for drilling wells with cleaning them from sludge with a gaseous blowing agent and can be used to create a backwater that exceeds the static pressure of the well fluid.

The purpose of the invention is to expand the field of application, increase reliability by eliminating the stitching of a drilling rod by products of destruction, maximizing the energy of the oncoming flow to increase the pressure of the blowing agent in the well, increasing the energy of the oncoming flow and increasing the pressure of the blowing agent in the well by increasing the resistance to movement

the combined stream formed after mixing the purge agent with the counter stream containing liquid by increasing its viscosity.

The drawing shows a device for implementing the method of drilling wells, a general view.

The device contains a slurry-receiving duct 1 of a gas-dumping outlet, a casing 2, a pipeline 3 and guide nozzles 4. Drill pipes 5 are passed through the slurry receiving duct 1.

The guide nozzles 4 may be in the form of nozzles placed around the circumference of the annulus.

SP

one

& & +4

with

or in the form of an annular gap exceeding the external diameter of the annulus. Valve 6 is installed on line 3.

The method is carried out as follows.

In the process of rock destruction, a gaseous purge agent (compressed air) is supplied to the drill pipe 5 and its pressure in the annulus is controlled by changing the flow resistance at the outlet by introducing counter flow into the annulus toward the outlet reverse flow gas, liquid or mixtures of them injected in the form of jets. The flow of the oncoming flow is carried out in the area of movement of the blowing agent at the highest speed (in casing 2) in order to maximize the use of the energy of the oncoming flow to increase the pressure of the blowing agent in the well. In order to increase the energy of the oncoming flow, amplifying additives may be added to the latter in the form of, for example, rock particles with frames that do not exceed the largest sizes of particles of destruction products carried by the blowing agent out of the well.

To increase the pressure of the purge agent in the well by increasing the resistance to movement of the combined stream formed after mixing the purge agent with the counter-stream containing fluid, by increasing its viscosity, foaming additives can also be added to the latter.

The gas stream supplied through the drill rod pipes 5 washes the bottom of the well, removes destruction products (drill cuttings) from the well and brings it to the surface in the sludge receiving duct 1 of the sludge pit. At the same time the gas sludge stream has

The highest SPEED in the cistern

be 2, narrowing the cross-section of the well.

In order to eliminate the inflow of water into the well and ensure efficient thermal drilling and expansion of the well, it is necessary to increase the pressure of the gaseous blowing agent in the well and squeeze water from the walls down to the bottom of the fractured mass from the cracks. For these purposes by master’s

d

Q

five

whether 3 is supplied as a purge agent, for example, compressed air, water or a mixture with a corresponding pressure and quantity, which enter the guide nozzles 4 and flow out at a certain speed towards the reverse (gas-slurry) flow, providing the necessary backwater, increase the pressure of the purge agent in well and squeeze the water from the walls of the wells along the cracks deep into the destroyed array.

In mining enterprises, the depth of blastholes usually does not exceed 18–20 m. The static water pressure in the well is 0.1-0.18 MPa. Therefore, the overpressure of the gas-sludge flow in the well should be 0.15-0.2 MPa, which ensures the extraction of water from the walls of the well and effective thermal expansion of rocks.

Regulation of the pressure and amount of air, water or a mixture thereof for supporting the gas-slurry flow in the casing 2 is performed by valve 6 of line 3, ensuring the necessary speed of the oncoming flow (counterflow, according to the calibration data.

Calibration of valve 6 of line 3 is carried out in the range of overpressure (overpressure of the purge agent) 0.05-0.2 MPa. ,

The installation of a rational thermal expansion mode is performed as follows.

Before thermal expansion, a static pressure (height of a water column) is measured in a well previously drilled by a roller cone. A well casing 2 is installed at the wellhead, which is centered and secured by plugging. A thermal well expansion machine runs into a well, launches a thermal drill into Pa-4, lowers it into the well to the upper boundary of the future boiler cavity, transfers the operation of a thermal drill to a fixed mode and sets 3 pressure at the valve 6 of the well equal to the static water pressure in the well, increased by 0.01 -. 0.02 MPa.

Claims (1)

1. The method of drilling wells, including the destruction of rock, hearth