CN201187279Y

CN201187279Y - Downhole differential pressure type normal open valve

Info

Publication number: CN201187279Y
Application number: CNU2007203053595U
Authority: CN
Inventors: 李志广; 陈敏义; 刘华; 黄大云
Original assignee: Dagang Oilfield Group Co Ltd
Current assignee: DRILLING TECHNOLOGY DEVELOPMENT COMPANY, TIANJIN DAGANG OILFIELD RESEARCH INSTITUTE OF PETROLEUM ENGINEERING; Dagang Oilfield Group Co Ltd
Priority date: 2007-12-03
Filing date: 2007-12-03
Publication date: 2009-01-28
Anticipated expiration: 2017-12-03

Abstract

The utility model relates to a differential pressure type normally opened valve and aims to replace the ordinary ball seat and the smoothness is kept between a pipe column and the ground after a packer is packed and restored. The principle that fluid interception produces differential pressure is utilized to design the structure of the valve. The valve is formed by connecting an upper joint, a shell body and lower joint. A valve plug is installed in an inner cavity of the shell body. A spring is installed in an annular cavity between the shell body and the valve plug. A seal head is installed in a fixed ring. The seal head is provided with a limit ring. The outer wall of the valve plug is a cylindrical step surface which is matched with three step surfaces of the inner walls of the shell body. A water passing groove is arranged on the excircle of the fixed ring of the normally opened valve. The normally opened valve has the advantages of convenient and reliable operation and use and high success rate, and can be used for a straight well, a horizontal well and a large extended reach well.

Description

The differential normal open valve in down-hole

Technical field

The utility model relates to the differential normal open valve in a kind of down-hole, is the down-hole string kit of oil field oil production by layer completion, and the down-hole completion tubular column that is particularly suitable for carrying out with hydraulic packer separate zone production is supporting, belongs to the special-purpose wellbore tool in the petroleum machinery.

Background technology

In oil mining and various underground work, usually use hydraulic base sealed packer, spherical seat valve is to be used for underground work construction and separate zone production flow string and the supporting instrument of packer, its effect is the bottom that is connected on running string, when suppressing, base sealed packer makes the sealing of tubing string bottom, guarantee packer seat envelope smoothly, job execution and normal exploitation are produced carry out smoothly that spherical seat valve generally is used in the hydraulic base sealed straight well.General spherical shape seat valve commonly used mainly contains two kinds of ball-throwing type and dribbling formulas.The ball-throwing type ball seat be with pedestal with under the tubing string lower going-into-well, drop into valve ball before the packer set again to pedestal, suppress and make packer set; And dribbling formula ball seat be with ball seat body and valve ball together with under the tubing string lower going-into-well, this ball seat causes packer seat envelope midway easily if use in the well of stratum deficit, influence construction quality.There is same drawback in above-mentioned two kinds of ball seats, promptly in construction or manufacturing process, steel ball is in the sealing surface place on the ball seat body all the time, and the consequence one that causes is to influence the effect of stratum to the oil pipe feed liquor, and the 2nd, because ball seat body sealing surface is taper (being the shape of falling the Eight characters), up big and down small, the steel ball place deposits booty, particularly sand output well easily, occurs sand when sand setting is serious and buries ball seat, can't produce, again operation.

The utility model content

The purpose of this utility model is to overcome the packer mistake seat that common ball seat in use exists, the feed liquor weak effect, deposition booty or sand bury drawbacks such as ball seat, the principle of utilizing liquid to dam to produce pressure reduction is carried out structure design, propose to satisfy the production demand equally with spherical seat valve on a kind of function, can replace common ball seat to use fully, the differential normal open valve in down-hole with different structure, guarantee and the supporting application of down-hole operating tool string, can guarantee the reliability of packer set, can make whole tubing string and stratum keep unimpeded again, guarantee the validity of tubing string, practicality.

The utility model adopts following technical scheme, be that the differential normal open valve in a kind of down-hole is by top connection 1, housing 4, spool 6, spring 3, seal head 7, retainer ring 8, baffle ring 9, lower contact 10 constitutes, it is characterized in that top connection 1, housing 4, lower contact 10 from top to bottom is fixedly connected sequentially, spool 6 is installed in the inner chamber of housing 4, spool 6 upper ends are spacing by the end face at top connection 1 step place, spring 3 is installed in the annular space of 6 of housing 4 and spools, spring 3 upper ends contact with step end face on spool 6 outer walls, and spring 3 lower ends are limited by housing 4 inwall small stair end faces; Retainer ring 8 is installed in housing 4 and lower contact 10 junctions, retainer ring 8 is spacing by housing 4 and lower contact 10, seal head 7 is installed in the centre bore of retainer ring 8, the screw thread of seal head 7 lower ends is threaded with baffle ring 9 inner peripherys, the circular hole screw thread is threaded with housing 4 lower end cylindricals in lower contact 10 upper ends, and lower contact 10 lower end external screw-threads are connected with operating tool string.

The inner chamber of the top connection 1 of the differential normal open valve in the utility model down-hole is up-small and down-big step screw thread, and its upper end screw thread is connected with operating tool string, and the lower end screw thread is connected with housing 4.

The differential normal open valve housing 4 in the utility model down-hole radially has two through holes 11.

Spring 3 is the compression spring, and spring 3 makes spool 6 not contact mutually with seal head 7; Baffle ring 9 prevents that seal head 7 from coming off from retainer ring 8.

Spool 6 outer walls of the differential normal open valve in the utility model down-hole are up big and down small cylinder table terrace.

The retainer ring 8 cylindricals design of the differential normal open valve in the utility model down-hole had tank, as shown in Figure 3, guaranteed the area of passage and the connection of instrument.

The inwall of the differential normal open valve housing 4 in the utility model down-hole has 3 step surfaces, and the inwall of housing 4 is up big and down small step vestibule; The big step inwall in housing 4 tops cooperates with the big end cylinder table of spool 6 outer walls terrace, and housing 4 bottom small stair inwalls cooperate with spool 6 outer wall small end cylinder table terraces, and last seal 2 and lower seal 5 sealings are arranged.

The area of spool 6 upper surfaces of the differential normal open valve in the utility model down-hole is greater than the area of housing 4 inner chamber small stair lower surfaces.

The big step of the spool 6 outer walls place end face of the differential normal open valve in the utility model down-hole arrives the distance of seal head 7 sealing surfaces greater than spool 6 lower surfaces to the distance of the big step end face of housing 4 inwalls.

The operating principle of the differential normal open valve in the utility model down-hole at first is connected the differential normal open valve in down-hole the lower end of working string, is lowered to the precalculated position with tubing string.Tubing string is lowered in the process, the normal open valve is often opened from start to finish, see as shown in Figure 1, oil jacket is communicated with, behind construction location, when needing base sealed packer, squeeze into liquid to oil pipe down from well head, produce when liquid is flowed through spool 6 and dam, cause the spool 6 inside and outside pressure reduction that produce, the pressure of generation acts on the spool 6, produces downward thrust, compression spring 3 is descending, the lower end of spool 6 is contacted with the circular cone of seal head 7 upper ends, reach sealing state, as shown in Figure 2, make oil pipe tubing string inner chamber form whole close encapsulation, both can improve the pressure seat sealed packer; Packer is finished seat and is honored as a queen, and stops to pressurize in oil pipe, and spool 6 is up under spring 3 bounce effects, breaks away from seal nipple 7, as shown in Figure 1, makes tubing string inside and outside unimpeded, and formation fluid is not subjected to any stopping successfully to enter tubing string, satisfies and produces needs.

The differential normal open valve in the utility model down-hole, reasonable in design, safe and reliable, when not suppressing, differential normal open valve is unimpeded, suppresses generation pressure reduction, spool and seal head are closed; After the pressure release, spring promotes spool and seal head is opened, and tubing string continues unimpeded, avoids occurring the phenomenon that seat seals and sand buries ball seat midway.This valve operation, easy to use, success rate is high, flexibly, reliable, both can be used for straight well, also can be used for horizontal well, extended reach well.

Description of drawings

Fig. 1, the differential normal open valve in the utility model down-hole (when often opening) structural representation;

Fig. 2, the differential normal open valve in the utility model down-hole (during hermetically closing) structural representation;

Fig. 3 is the A-A sectional drawing of Fig. 2;

Among the figure: top connection 1, last sealing ring 2, spring 3, housing 4, lower seal 5, spool 6, seal head 7, retainer ring 8, baffle ring 9, lower contact 10, through hole 11.

The specific embodiment

Below in conjunction with drawings and Examples structure of the present utility model is further specified, the differential normal open valve in the utility model down-hole, constitute by top connection 1, spring 3, housing 4, seal head 6, lower contact 10, be positioned at the internal thread of top connection 1 at differential normal open valve two ends, down-hole and the external screw thread of lower contact 10 and be connected with operating tool string respectively.

Top connection 1, housing 4, lower contact 10 from top to bottom are fixedly connected sequentially.Top connection 1 is threaded with housing 4; Housing 4 is threaded with lower contact 10.Spool 6 is installed in the endoporus of housing 4, and spring 3 is the compression spring, is installed between spool 6 and housing 4 annular spaces, and spool 6 is not contacted with seal head 7.Seal head 7 is installed in the centre bore of retainer ring 8, and the screw thread of seal head 7 lower ends is threaded with baffle ring 9 inner peripherys, prevents that seal head 7 breaks away from from retainer ring 9;

Retainer ring 8 is installed in the middle part of housing 4 and lower contact 10 junctions, and spacing by housing 4 and lower contact 10, and the design of retainer ring 8 cylindricals has four to cross tank; Circle has screw thread to be connected with housing 4 in lower contact 10 tops, and the outside, lower end has screw thread to be connected with operating tool string.

Spool 6 external diameters are up big and down small step cylinder; The interior circular hole of housing 4 has 3 step surfaces at least, and endoporus is up big and down small stepped hole; The big inner bore of step in housing 4 tops cooperates with the big end cylinder of spool 6 external diameters, and bottom small stair endoporus cooperates with spool external diameter small column, and has seal 2,5 to do sealing; The area of spool 6 upper surfaces is greater than the area of housing 4 endoporus small stair lower surfaces; The big step of spool 6 external diameters place end face arrives the distance of seal head 7 sealing surfaces greater than spool 6 lower surfaces to the distance of the big step end face of housing 4 endoporus.

The differential normal open valve in the utility model down-hole, operation, easy to use, success rate is high, flexibly, reliably unrestricted, of many uses, both can be used for straight well, also can be used for horizontal well, extended reach well.

Claims

1, the differential normal open valve in a kind of down-hole is by top connection (1), housing (4), spool (6), spring (3), seal head (7), retainer ring (8), baffle ring (9), lower contact (10) constitutes, it is characterized in that top connection (1), housing (4), lower contact (10) from top to bottom is fixedly connected sequentially, spool (6) is installed in the inner chamber of housing (4), spool (6) upper end is spacing by the end face at top connection (1) step place, spring (3) is installed in the annular space between housing (4) and spool (6), spring (3) upper end contacts with step end face on spool (6) outer wall, spring (3) lower end is limited by housing (4) inwall small stair end face, retainer ring (8) is installed in housing (4) and lower contact (10) junction, retainer ring (8) is spacing by housing (4) and lower contact (10), seal head (7) is installed in the centre bore of retainer ring (8), the screw thread of seal head (7) lower end is threaded with baffle ring (9) inner periphery, the circular hole screw thread is threaded with housing (4) lower end cylindrical in lower contact (10) upper end, and lower contact (10) lower end external screw-thread is connected with operating tool string.

2, the differential normal open valve in down-hole as claimed in claim 1, the inner chamber that it is characterized in that top connection (1) is up-small and down-big step screw thread, and its upper end screw thread is connected with operating tool string, and the lower end screw thread is connected with housing (4).

3, the differential normal open valve in down-hole as claimed in claim 1 is characterized in that spool (6) outer wall is up big and down small cylinder table terrace.

4, the differential normal open valve in down-hole as claimed in claim 1, the inwall that it is characterized in that housing (4) has three step surfaces, the inwall of housing (4) is up big and down small step vestibule, the big step inwall in housing (4) top cooperates with the big end cylinder table of spool (6) outer wall terrace, housing (4) bottom small stair inwall cooperates with spool (6) outer wall small end cylinder table terrace, and last seal (2) and lower seal (5) sealing are arranged.

5, the differential normal open valve in down-hole as claimed in claim 1 is characterized in that retainer ring (8) cylindrical had tank.

6, the differential normal open valve in down-hole as claimed in claim 1 is characterized in that the area of the area of spool (6) upper surface greater than housing (4) inner chamber small stair lower surface.

7, the differential normal open valve in down-hole as claimed in claim 1 is characterized in that the big step of spool (6) outer wall place end face arrives the distance of seal head (7) sealing surface greater than spool (6) lower surface to the distance of the big step end face of housing (4) inwall.

8, the differential normal open valve in down-hole as claimed in claim 1 is characterized in that housing (4) radially has two through holes (11).