Unlock instant, AI-driven research and patent intelligence for your innovation.

Construction method of coiled tubing drilling and grinding underbalanced cement plug operation

A construction method and cement plug technology are applied in the field of construction, coiled tubing drilling and grinding underbalanced cement plug operation, and can solve the problems of high trap pressure, inability to control the wellhead balanced pressure in the drilling and grinding process, and low construction efficiency. The effect of preventing blowouts, improving operational efficiency and process safety levels

Active Publication Date: 2019-06-18
BC P INC CHINA NAT PETROLEUM CORP +1
View PDF5 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] (1) The pipe string structure of traditional tubing drilling and grinding usually adopts tubing (or drill pipe) + screw drill + grinding shoe or tricone, or uses wellhead power (turntable, power faucet) + tubing (or drill pipe) + grinding Shoes or tricones, because the position of the wellhead cement plug is shallow, it is difficult to add drilling weight, and the construction efficiency is low;
[0005] (2) The cement plug itself is the purpose of sealing the reservoir. After long-term accumulation, there may be high trap pressure. The cement plug at the wellhead or at a shallower position is in an underbalanced state. The traditional drilling and grinding process cannot control the wellhead balance pressure , when drilling through the cement plug, there is a risk of instantaneous release of accumulated natural gas in the wellbore, ejection from the top of the drilling tool, or even blowout

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
  • Construction method of coiled tubing drilling and grinding underbalanced cement plug operation
  • Construction method of coiled tubing drilling and grinding underbalanced cement plug operation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] A coiled tubing drilling and grinding underbalanced cement plug operation construction method, the method specifically is to first use the ground choke manifold 10 to control, maintain the balance pressure in the wellbore 7 above the cement plug, and then use the small-diameter grinding shoe 5 or small drill bit to load the drill pressure, drill and grind the cement plug 8; when drilling through the cement plug 8, release the balance pressure P 套 and liquid column pressure P 液 To balance the wellbore trap pressure P under the cement plug 地 ; Bleeding and releasing the pressure through the discharge port 11, circulating the wellbore; and then changing the large-diameter grinding shoe 9 to clean up the cement plug until the cement plug is completely drilled out.

Embodiment 2

[0035] Such as figure 1 As shown, a coiled tubing drilling and grinding underbalanced cement plug operation construction method specifically includes the following steps:

[0036] Step 1): Install and inspect the coiled tubing equipment and the ground choke manifold 10, connect the discharge pipe of the coiled tubing equipment to the ground choke manifold through the wellhead cross 3, and install the anti-seismic pressure on the upper part of the wellbore 7 Table: The coiled tubing of the coiled tubing equipment is connected in series with the tool string with the small-diameter grinding shoe 5 and merged into the well;

[0037] Step 2): The tool pipe string with the small-diameter grinding shoe 5 is probed to the cement plug surface; the tool pipe string with the small-diameter grinding shoe 5 is composed of a coiled tubing joint, a motor head assembly, a screw motor and a small-diameter grinding shoe 5 are connected from top to bottom; the diameter of the small-diameter gri...

Embodiment 3

[0049] On the basis of Example 2, the initial section of the coiled tubing must be straightened by more than 2 meters to ensure that the tool string is centered during drilling and grinding. Step 8) When replacing the tool pipe string with a large-diameter grinding shoe to clean the cement plug, it is not necessary to control the sleeve to release the balance pressure P 套 .

[0050] The coiled tubing equipment mainly includes a power source 1, an injection head 2, a blowout preventer, a connecting oil pipe, a blowout pipe, etc., and the connecting oil pipe passes through the wellhead cross 3 on the wellbore 7 and is connected to the connecting oil pipe joint of the tool string 4 , the tool pipe string 4 is a tool pipe string with a small-diameter grinding shoe or a tool pipe string with a large-diameter grinding shoe. The blowout preventer is connected with the ground choke manifold 10; the power source 1 includes a diesel engine, pump, fuel tank and control system; the coile...

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 relates to a construction method of coiled tubing drilling and grinding underbalanced cement plug operation. The construction method specifically includes the steps that a ground choke manifold is first used for controlling, the balanced pressure is maintained on a shaft on the upper part of a cement plug, then small-diameter grinding shoes or a drillroid are used for loading the bitweight, and the cement plug is drilled and ground; when drilling through the cement plug, the shaft trap pressure P<ground> on the lower part of the cement plug is balanced through the balance pressure P<sleeve> sleeving on the upper part of the cement plug and the liquid column pressure P<liquid>; the pressure is discharged and relieved through a discharge nozzle, and the shaft is cycled; and the large-diameter grinding shoes are then replaced to clear the cement plug, until the cement plug is completely drilled. According to the construction method of coiled tubing drilling and grinding underbalanced cement plug operation, the difficult problem of the high well control risk of cement plugs in traditional drilling and grinding wellheads or shallow well sections is solved, site builders master and operate conveniently, and the workover treatment level is improved advantageously.

Description

technical field [0001] The invention relates to a construction method, in particular to a construction method for coiled tubing drilling and grinding underbalanced cement plug operation. It belongs to the field of oil and gas field workover. Background technique [0002] The underbalanced cement plug mainly refers to the fact that the cement plug is in the shallow position of the wellhead or the wellbore, and there may be trap pressure in the lower part of the cement plug, and the pressure is greater than the liquid column pressure in the upper part of the cement plug. The existing drilling and grinding measures mainly adopt the traditional tubing (or drill pipe) drilling and grinding process, which has a high risk of well control and can no longer meet the needs of on-site construction. [0003] mainly reflects in: [0004] (1) The pipe string structure of traditional tubing drilling and grinding usually adopts tubing (or drill pipe) + screw drill + grinding shoe or trico...

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
IPC IPC(8): E21B29/00
Inventor 刘国良刘小会谢涛陈世波席仲琛陈文博祁俊武段腾龙景志明
Owner BC P INC CHINA NAT PETROLEUM CORP