CN213392110U

CN213392110U - Composite seam type sieve tube

Info

Publication number: CN213392110U
Application number: CN202020660396.3U
Authority: CN
Inventors: 高福万; 陈静; 杨贺来
Original assignee: TIANJIN ZHONGJIE TECHNOLOGY DEVELOPMENT CO LTD
Current assignee: TIANJIN ZHONGJIE TECHNOLOGY DEVELOPMENT CO LTD
Priority date: 2020-04-27
Filing date: 2020-04-27
Publication date: 2021-06-08
Anticipated expiration: 2030-04-27

Abstract

The utility model relates to a composite slot type sieve tube, the section structure of which is formed by combining a plurality of straight slots or curves, and the straight slots or the curves are continuously connected and are gradually diffused. The composite seam is formed by combining an outer long and narrow rectangular seam, a small transition trapezoidal seam and an inner large trapezoidal seam, wherein the outer long and narrow rectangular seam is positioned near the excircle of the pipe, the inner large trapezoidal seam is positioned near the inner hole of the pipe, the upper end of the small transition trapezoidal seam is connected with the outer long and narrow trapezoidal seam, the lower end of the small transition trapezoidal seam is connected with the inner large trapezoidal seam, and the section of the seam from the outside of the pipe to the inside of the pipe is enlarged section by section. The length-width ratio of the outer long and narrow rectangular seam can be 10:1, the width of the outer seam can be more than or equal to 0.10 mm, and the depth of the outer seam can be more than or equal to 2.50 mm. The taper angle of the small transition trapezoidal seam is 3-6 degrees, and the taper angle of the inner large trapezoidal seam is 6-12 degrees. The sieve tube can replace the traditional rectangular slot sieve tube and the trapezoidal slot sieve tube, thereby improving the oil recovery rate and prolonging the service life of the sieve tube.

Description

Composite seam type sieve tube

Technical Field

The utility model discloses a compound seam type screen pipe belongs to an oil well sand control downhole machines.

Background

At present, the slotted structures of slotted screen pipes commonly used at home and abroad are all rectangular slots and trapezoidal slots. The two seam types have the defects of low oil extraction efficiency, poor abrasion resistance and the like respectively.

The rectangular slot slotted screen pipe has the same slot width from the outer wall of the pipe to the inner wall of the pipe, and the geometric shape is like a rectangle. The seam has simple structure, convenient processing, wide grinding width of the seam by gravel which is not easy to be extruded into the pipe body, and strong wear resistance. But the oil extraction efficiency is low, the engineering reliability is poor, namely the filtering self-cleaning performance is poor, gravel blockage, "sand jamming", "pump jamming" and even serious accidents such as well collapse, production halt and the like are easily caused.

The outer edge of the slit of the trapezoid slit slotted screen pipe is narrow, the inner edge of the slit of the trapezoid slit slotted screen pipe is wide, the geometric shape of the slit slotted screen pipe is a symmetrical trapezoid, and the cone angle is generally 12 degrees. The trapezoid slit has good filtering self-cleaning property, is not easy to generate sand blockage, and can greatly improve the oil production. However, when viewed from the cross section of the trapezoid slit sieve tube, the outer slit cross section and the outer circle of the tube form a sharp cutting edge, which is easily abraded by running sand, so that the outer slit is widened, and the sand filtering precision is affected. Moreover, the sharp cutting edge causes stress concentration, so that the strength of the tube body is reduced.

Disclosure of Invention

In order to overcome the defects of the seam type of the existing slotted screen pipe, the invention provides a composite seam type screen pipe.

The utility model provides a compound slit type screen pipe, its section structure is formed by a plurality of straight slots or curve combination, its characterized in that: the straight seam or the curve is continuously connected and gradually diffused, the composite seam is formed by combining an outer long and narrow rectangular seam, a small transition trapezoidal seam and an inner large trapezoidal seam, the outer long and narrow rectangular seam is positioned close to the excircle of the pipe, the inner large trapezoidal seam is positioned close to the inner hole of the pipe, the upper end of the small transition trapezoidal seam is connected with the outer long and narrow trapezoidal seam, the lower end of the small transition trapezoidal seam is connected with the inner large trapezoidal seam, and the section of the seam from the outside of the pipe to the inside of the pipe is enlarged section by section.

The compound slot type screen pipe is characterized in that: the length-width ratio of the outer long and narrow rectangular seam is 10:1, the width of the outer seam is more than or equal to 0.10 mm, and the depth of the outer seam is more than or equal to 2.50 mm.

The compound slot type screen pipe is characterized in that: the taper angle of the small transition trapezoidal seam is 3-6 degrees, and the taper angle of the inner large trapezoidal seam is 6-12 degrees.

The invention has the advantages that the straight seams or curves of all the sections are continuously connected and gradually diffused, the outer long and narrow rectangular seam absorbs the advantages of the rectangular seam screen pipe, and the seam resists the abrasion of gravel. The inner large trapezoid seam absorbs the advantages of the trapezoid seam and has good filtering and self-cleaning properties. Combining the results of the two seam types, the outer long and narrow rectangular seam can maintain the sand filtering precision of the combined seam screen pipe and reduce the abrasion of the sand to the seam. The large inner trapezoid seam can increase the flow area and improve the oil extraction. The middle small transition trapezoidal seam plays a role in connecting the outer seam with the inner seam and enabling oil flow to gradually transit and gradually diffuse. The sieve tube can replace the traditional rectangular slot sieve tube and the trapezoidal slot sieve tube, thereby improving the oil recovery rate and prolonging the service life of the sieve tube.

Drawings

The invention is further explained below with reference to the drawings and the embodiments.

FIG. 1 is a schematic cross-sectional view of a composite slotted screen.

Detailed Description

In the figure, the cross section structure of the composite slit type sieve tube is formed by combining a plurality of straight slits or curves, the straight slits or curves are continuously connected and gradually spread, the composite slit type sieve tube is formed by combining an outer long and narrow rectangular slit 1, a small transition trapezoidal slit 2 and an inner large trapezoidal slit 3, the outer long and narrow rectangular slit 1 is positioned close to the excircle of a tube, the inner large trapezoidal slit 3 is positioned close to the inner hole of the tube, the upper end of the small transition trapezoidal slit 2 is connected with the outer long and narrow trapezoidal slit 1, the lower end of the small transition trapezoidal slit 2 is connected with the inner large trapezoidal slit 3, and the section of the slit from the outside of the tube to the inside of the tube is gradually enlarged.

The composite slit type sieve tube is characterized in that an outer long and narrow rectangular slit 1 is close to the outer circle of the tube, an inner large trapezoidal slit 3 is close to the inner hole of the tube, and a small transition trapezoidal slit 2 is connected with the outer long and narrow rectangular slit and the inner large trapezoidal slit. The sand inclusion of crude oil enters the pipe body from the outside of the pipe body, firstly enters the outer long and narrow rectangular seam 1, the width of the outer seam is small, large gravel can be separated outside the pipe body, the sand filtering precision is improved, and only fine sand is allowed to enter the pipe. The outer seam is narrow, and simultaneously the outer seam is darker, improves the sand gravel abrasion resistance life of outer rectangle section gap.

The taper angle of the small transition trapezoidal seam 2 of the composite seam type sieve tube is 3-6 degrees, so that oil-contained sand is gradually transited and gradually diffused in the tube body. If the oil suddenly changes from the outer long and narrow rectangular slit 1 to a large diffusion surface, the oil contracts to form turbulent flow, so that local pressure loss is caused, and the flow velocity of the crude oil is reduced. Therefore, there is a small transition trapezoidal slit 2.

The cone angle of the inner large trapezoidal seam 3 of the composite seam type sieve tube is 6-12 degrees. The oil sand is diffused as soon as possible, the flow area is increased, and the oil extraction rate is improved.

Claims

1. The utility model provides a compound slit type screen pipe, its section structure is formed by a plurality of straight slots or curve combination, its characterized in that: the straight seam or the curve is continuously connected and gradually diffused, the composite seam is formed by combining an outer long and narrow rectangular seam, a small transition trapezoidal seam and an inner large trapezoidal seam, the outer long and narrow rectangular seam is positioned close to the excircle of the pipe, the inner large trapezoidal seam is positioned close to the inner hole of the pipe, the upper end of the small transition trapezoidal seam is connected with the outer long and narrow trapezoidal seam, the lower end of the small transition trapezoidal seam is connected with the inner large trapezoidal seam, and the section of the seam from the outside of the pipe to the inside of the pipe is enlarged section by section.

2. The composite slotted screen of claim 1, wherein: the length-width ratio of the outer long and narrow rectangular seam is 10:1, the width of the outer seam is more than or equal to 0.10 mm, and the depth of the outer seam is more than or equal to 2.50 mm.

3. The composite slotted screen of claim 1, wherein: the taper angle of the small transition trapezoidal seam is 3-6 degrees, and the taper angle of the inner large trapezoidal seam is 6-12 degrees.