Flow splitting device for gas reverse circulation drilling

Patent metadata

Field	Value
Publication number	US-11946334-B2
Application number	US-202017913075-A
Country	US
Kind code	B2
Filing date	Sep 30, 2020
Priority date	Apr 6, 2020
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

A flow splitting device for gas reverse circulation drilling, including: an upper joint for connecting with a double-wall drill pipe; an inner tube which is arranged in the upper joint and defines a first passageway in communication with an inner chamber of the double-wall drill pipe, a second passageway in communication with an annular space in the double-wall drill pipe formed between the inner tube and the upper joint; a lower joint, having an upper end fixedly connected with the upper joint and a lower end for connecting with a drill tool; and a flow guiding member provided between the upper joint and the lower joint. A flexible sealing mechanism is provided outside the upper joint. The flexible sealing mechanism extends radially outward relative to the upper joint and the lower joint to form a sealing contact with a wellbore wall.

First claim

The invention claimed is:

1. A flow splitting device for gas reverse circulation drilling, comprising:
an upper joint for connecting with a double-wall drill pipe;
an inner tube, which is arranged in the upper joint and defines a first passageway in communication with an inner chamber of the double-wall drill pipe, a second passageway in communication with an annular space of the double-wall drill pipe formed between the inner tube and the upper joint;
a lower joint, having an upper end fixedly connected with the upper joint and a lower end for connecting with a drill tool; and
a flow guiding member provided between the upper joint and the lower joint, for allowing gas from the annular space of the double-wall drill pipe to enter into the drill tool after passing through the second passageway, and gas from the drill tool to return to a wellhead after passing through the first passageway and the inner chamber of the double-wall drill pipe,
wherein a flexible sealing mechanism is provided on the upper joint, so that the upper joint is rotatable relative to the flexible sealing mechanism, the flexible sealing mechanism extending radially outward relative to the upper joint and the lower joint to form a sealing contact with a wellbore wall,
wherein the flexible sealing mechanism comprises a plurality of sealing units arranged on the upper joint along an axial direction, each of the sealing units including a pressing disc arranged around an outer periphery of the upper joint, and a flexible ring fixed on the pressing disc, the flexible ring extending radially outward from the pressing disc to form the sealing contact with the wellbore wall.

2. The flow splitting device for gas reverse circulation drilling according to claim 1 , wherein the flexible ring is embedded therein with a rigid ring, which is fixed on the pressing disc.

3. The flow splitting device for gas reverse circulation drilling according to claim 2 , wherein the pressing disc has a step, on which the rigid ring and the flexible ring are both arranged.

4. The flow splitting device for gas reverse circulation drilling according to claim 1 , wherein a plurality of axial slots spaced apart from each other is formed on an inner surface of the pressing disc, a wear-resistant strip being arranged in each of the axial slots.

5. The flow splitting device for gas reverse circulation drilling according to claim 1 , wherein a first compensation member and a second compensation member are arranged on the outer periphery of the upper joint, the flexible sealing mechanism being arranged between the first compensation member and the second compensation member.

6. The flow splitting device for gas reverse circulation drilling according to claim 5 , wherein engaging surfaces between adjacent pressing discs, between the pressing disc and the first compensation member and between the pressing disc and the second compensation member are each provided with a wear-resistant element.

7. The flow splitting device for gas reverse circulation drilling according to claim 6 , wherein the wear-resistant element is configured as a column made of cemented carbide.

8. The flow splitting device for gas reverse circulation drilling according to claim 5 , wherein a locking sleeve is provided on the upper joint for forming a fixing connection with an upper end of the first compensation member, and a lower end of the second compensation member is fixedly connected with the lower joint.

9. The flow splitting device for gas reverse circulation drilling according to claim 1 , wherein the gas from the annular space of the double-wall drill pipe is compressed gas, and the gas from the drill tool carries cuttings.

10. A flow splitting device for gas reverse circulation drilling, comprising:
an upper joint for connecting with a double-wall drill pipe;
an inner tube, which is arranged in the upper joint and defines a first passageway in communication with an inner chamber of the double-wall drill pipe, a second passageway in communication with an annular space of the double-wall drill pipe formed between the inner tube and the upper joint;
a lower joint, having an upper end fixedly connected with the upper joint and a lower end for connecting with a drill tool; and
a flow guiding member provided between the upper joint and the lower joint, for allowing gas from the annular space of the double-wall drill pipe to enter into the drill tool after passing through the second passageway, and gas from the drill tool to return to a wellhead after passing through the first passageway and the inner chamber of the double-wall drill pipe,
wherein a flexible sealing mechanism is provided on the upper joint, so that the upper joint is rotatable relative to the flexible sealing mechanism, the flexible sealing mechanism extending radially outward relative to the upper joint and the lower joint to form a sealing contact with a wellbore wall,
wherein a plurality of blind holes spaced from each other is formed in an outer surface of the upper joint, a wear-resistant column being arranged in each of the blind holes.

11. A flow splitting device for gas reverse circulation drilling, comprising:
an upper joint for connecting with a double-wall drill pipe;
an inner tube, which is arranged in the upper joint and defines a first passageway in communication with an inner chamber of the double-wall drill pipe, a second passageway in communication with an annular space of the double-wall drill pipe formed between the inner tube and the upper joint;
a lower joint, having an upper end fixedly connected with the upper joint and a lower end for connecting with a drill tool; and
a flow guiding member provided between the upper joint and the lower joint, for allowing gas from the annular space of the double-wall drill pipe to enter into the drill tool after passing through the second passageway, and gas from the drill tool to return to a wellhead after passing through the first passageway and the inner chamber of the double-wall drill pipe,
wherein a flexible sealing mechanism is provided on the upper joint, so that the upper joint is rotatable relative to the flexible sealing mechanism, the flexible sealing mechanism extending radially outward relative to the upper joint and the lower joint to form a sealing contact with a wellbore wall,
wherein the flow guiding member is a hollow cylinder, which has an inner chamber in communication with the first passageway; and
a third passageway extending through the flow guiding member axially is provided in a wall of the flow guiding member, wherein one end of the third passageway is in communication with the second passageway and the other end thereof is in communication with the drill tool.

12. The flow splitting device for gas reverse circulation drilling according to claim 11 , wherein the flow guiding member comprises two third passageways radially opposite to each other, each third passageway being configured to have a cross section of arc shape.

13. The flow splitting device for gas reverse circulation drilling according to claim 12 , wherein a first radial through hole is formed in a wall of the lower joint, and a second radial through hole is formed in the wall of the flow guiding member, and
the second radial through hole is at least partially aligned with the first radial through hole, so that the gas from the drill tool is able to enter the inner chamber of the flow guiding member after passing through the first radial through hole and the second radial through hole.

14. The flow splitting device for gas reverse circulation drilling according to claim 13 , wherein the first radial through hole

Assignees

• China Petroleum & Chem Corp
• Sinopec Petroleum Engineering Tech Service Co Ltd
• Sinopec Shengli Petroleum Eng Co Ltd
• Drilling Tech Research Institute Of Sinopec Shengli Petroleum Engineering Co Ltd

Inventors

• Zhao Chuanwei
• Wu Zhonghua
• Zhou Yanjun
• Tang Honglin
• Liu Zhihe
• Pei Xueliang
• Sun Haoyu
• Su Zhenguo
• Kang Bo
• Zhang Hui
• Zhu Huangang
• Chen Yongming
• Chen Zhongshuai

Classifications

• E21B33/128 Primary

  with a member expanded radially by axial pressure (E21B33/122, E21B33/124 take precedence) · CPC title

• E21B21/12 Primary

  using drilling pipes with plural fluid passages, e.g. closed circulation systems · CPC title

• E21B21/16

  using gaseous fluids (E21B21/14 takes precedence) · CPC title

• E21B21/103

  Down-hole by-pass valve arrangements, i.e. between the inside of the drill string and the annulus (valves specifically for maintaining circulation of drilling fluid while connecting or disconnecting tubular joints E21B21/019) · CPC title