Selective refracturing technology for old oilfield wells

A re-fracturing and selective technology, applied in wellbore/well components, production fluids, earth-moving drilling, etc., can solve the problem of inability to meet the requirements of isolating the upper reformed interval, affecting oil well productivity, compaction damage, etc. problem, to achieve the effect of flexible construction method, simple structure and reduced rupture pressure

Active Publication Date: 2016-09-07
PETROCHINA CO LTD
View PDF5 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For old wells, the newly designed stimulated interval may be distributed in the middle of the stimulated interval, and conventional strings cannot meet the requirements of isolating the upper stimulated interval
Double seal single card fracturing requires conventional perforation for all construction intervals of the construction well, which is likely to cause compaction damage when the near wellbore zone is formed, and affect the productivity of the oil well

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
  • Selective refracturing technology for old oilfield wells
  • Selective refracturing technology for old oilfield wells
  • Selective refracturing technology for old oilfield wells

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0019] refer to Figures 1 to 5 The embodiment of the technology of the present invention is further described:

[0020] Taking an old horizontal well in an oil field as an example, there are two intervals that have been transformed, and now it is necessary to re-perforate and add two intervals to be transformed. The process string used in this construction consists of oil pipe 1, safety hand 2, upper packer 3, middle packer 4, hydraulic jet 5, lower packer 6, ball seat 7, check valve 8, eye pipe 9 and plug 10 form.

[0021] The concrete process steps of the technology of the present invention are as follows:

[0022] 1) According to the needs of repeated transformation and the designed interval, assemble and lower the pipe string (see figure 2 );

[0023] 2) Drag the pipe string several times to complete the perforation operation in the required reformed layer (see figure 2 , 3 );

[0024] 3) After the perforation of all intervals to be reformed is completed, the pip...

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 discloses a selective repeated fracturing technology for old wells in oil fields, which is designed for effectively solving the problem of repeated reformation of old wells in oil fields. The technology of the present invention adopts assembling, lowering the pipe string, and dragging the pipe string to complete the perforation operation of the required reformed layer, set the upper and middle packers, carry out the fracturing construction of the lowest newly added layer, unseal and drag The construction is carried out in the technological steps from moving the pipe string to the second newly-increased reconstruction layer. The technology of the invention utilizes hydraulic sand blasting perforation to form large-diameter and deep-penetrating tunnels, which can effectively reduce the fracture pressure, and utilizes the advantages of double-seal and single-clamp fracturing technology to reduce requirements on wellhead matching and casing steel grades. The technical string structure of the invention is simple, the construction method is flexible, the operation is convenient and the efficiency is high, which can effectively solve the problem of repeated reconstruction of old wells in the oil field, and can not only complete the repeated fracturing of the reconstructed section, but also carry out the hole repair of the newly added section Integrated operation with fracturing.

Description

technical field [0001] The invention relates to a selective repeated fracturing process for an old well in an oil field, and belongs to the technical field of oil and gas field fracturing. Background technique [0002] Conventional hydraulic sandblasting fracturing is to drag the hydraulic sandblasting fracturing string with bottom seal to carry out multi-layer or multi-stage fracturing of construction wells, which can only ensure the isolation of the lower layers that have been constructed. For old wells, the newly designed stimulated intervals may be distributed in the middle of the stimulated intervals, and conventional strings cannot meet the requirements of isolating the upper stimulated intervals. For double-seal and single-chamber fracturing, conventional perforation needs to be performed on all construction intervals of the construction well, which is likely to cause compaction damage in the vicinity of the wellbore when the hole is formed, and affect the productivit...

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 Patents(China)
IPC IPC(8): E21B43/26
Inventor 冯飞付钢旦桂捷任勇冯长青何华刘明
Owner PETROCHINA CO LTD
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