Protection process of underground drilling hole

A technology of a process and a protection device, which is applied in the field of small-scale engineering construction deep underground, can solve problems such as incomplete drilling, scrapped drilling, and silting.

Active Publication Date: 2010-06-23
ENN SCI & TECH DEV
View PDF6 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the relatively small diameter of the borehole (generally less than 1000mm), the soft coal seam, the inability to use it immediately after completion, and various factors, the coal seam section drilling and horizontal directional drilling are prone to diameter shrinkage, hole collapse, and silting, etc. As a result, the drilling holes are not complete enough during use, and need to be processed again, and even the drilling holes are scrapped.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Protection process of underground drilling hole
  • Protection process of underground drilling hole
  • Protection process of underground drilling hole

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037]In this embodiment, directional drilling and vertical drilling will be constructed, and the drilling protection process for both will be implemented. Here, the combination figure 1 Give specific implementation steps.

[0038] First, build a vertical borehole 1 from the ground to the coal seam floor 5 through the surface soil layer 2, rock formation, coal seam roof 3 and coal seam 4, and estimate the position of the lower end of the borehole casing according to the previous drilling data and the calculation formula provided by the present invention. h 2 and borehole protector lower end position H 1 , in the Gonggou coalfield of Xinao Wellless Underground Coal Gasification Ulanqab Test Base, the depths to the ground are 277 meters and 289 meters respectively. When drilling to the lower end position H of the expected drilling casing 2 At the same time, the drilling casing 7 is lowered into the borehole 1, and the drilling casing and the formation are consolidated togethe...

Embodiment 2

[0044] combine figure 2 The implementation steps of the vertical drilling protection process are described.

[0045] First, use a drilling rig to drill a hole 1 from the ground to the coal seam floor 5 through the surface soil layer 2, the rock layer, the coal seam roof 3, and the coal seam 4. Referring to the previous drilling work in the Ulanchabu Gonggou coalfield, the coal seam is roughly buried. The depth, thickness and other conditions have been mastered, and the position H of the lower end of the drilling casing can be estimated 2 It is 277 meters deep and the lower end position of the drilling protection device is H 1 It is 289 meters deep, after drilling to the lower end position H of the expected drilling casing 2 When the well is washed, the drilling casing 7 is lowered to the bottom of the hole (the lower end of the drilling casing 7) in the borehole 1, and the cement slurry is injected into the well to cement the drilling casing 7 and the formation together. A...

Embodiment 3

[0051] combine here image 3 The implementation method of the socketed drilling protection process is specifically stated.

[0052] First, build a vertical borehole 1 from the ground to the underground coal seam, pass through the surface soil layer 2, the rock layer, the coal seam roof 3, and the coal seam 4, and drill into or even penetrate the coal seam floor 5. According to the drilling data and coal seam Coring situation, estimate the position H of the lower end of the drilling casing 2 It is 277 meters deep and the lower end position of the drilling protection device is H 1 It is 289 meters deep, and then estimate the amount of grouting cement required for hole bottom reinforcement based on the diameter and depth of the drilled hole.

[0053] Secondly, wash the borehole. After cleaning the mud used for drilling, inject the estimated amount of mud to reinforce the bottom of the hole and wait for solidification to form the bottom reinforcement of the borehole 6 .

[0054...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a protection process of an underground drilling hole, which comprises the following steps of: as for a directional drilling hole (8), arranging a horizontal drilling hole supporting pipe or filling a mixed foaming firming agent in the drilling hole at a horizontal segment after finishing the well cementation of a drilling hole sleeve pipe (9) at a vertical segment; and / or as for a vertical drilling hole (1), firstly reinforcing the hole bottom of the drilling hole, then arranging a drilling hole protection device (10) or filling the mixed foaming firming agent. In the invention, an open hole segment is effectively protected after drilling is finished, thereby not only ensuring that the drilling hole is not blocked before utilized, but also ensuring that the protection measures of the drilling hole can not influence the free flow of a fluid between the drilling hole and a coal layer when in utilization.

Description

technical field [0001] The invention relates to the construction of small-scale deep underground projects, in particular to the protection technology for preventing borehole diameter shrinkage, hole collapse, silting, blockage, etc. in underground coal seams. Background technique [0002] In the process of coalbed methane mining and underground coal gasification, especially in the wellless underground coal gasification, it is necessary to continuously extend the gasification channel to provide new gasifiable coal resources, which requires continuous replenishment from the ground to the coal seam in advance drilling. Usually, due to the relatively small diameter of the borehole, if the completed borehole is not well protected, it is easy to be blocked due to stratum creep, debris spalling, water gushing, etc. During the construction of underground coal gasification boreholes, the coal seam There are drilling casings inside and below the above part of the borehole, and the ou...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): E21B43/295E21B43/10E21B33/038
Inventor 贺岩潘霞宋玉平梁杰庞旭林
Owner ENN SCI & TECH DEV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products