US2365872A

US2365872A - Means for cleaning well screens

Info

Publication number: US2365872A
Application number: US447069A
Authority: US
Inventors: Norris E Gunderson
Original assignee: LAYNE NORTHERN Co Inc
Current assignee: LAYNE NORTHERN Co Inc; LAYNE-NORTHERN COMPANY Inc
Priority date: 1942-06-15
Filing date: 1942-06-15
Publication date: 1944-12-26
Anticipated expiration: 1961-12-26

Description

Dec. 26, 1944. N. E. GUNDERSON MEANS FOR CLEANING WELL SCREENS Filed June 15, 1942 2 Sheets-Sheet l u hO 0 a 3%. ma w a... wow. x flw wwkw m 6 o o .mm

INVENTOR. Mai/.15 iw/z/flf/raan,

w MM N. E. GUNDERSON MEANS FOR GLEAfiING WELL SCREENS Filed June 15. 1942 2 Sheets-Sheet 2 INVENTOR. BY Maw/.11.? fu/vam'aozr rams-someones omen;* m rmur.- oriflce as, 1

This invention relates to well cleaners, and specifically contemplates means for washing the clogged perforations of well casins reens and portions of the surrounding strata. by segregating limited areas of the screen structure inorder Much time and study has been heretofore directed to this question of segregating areas of" the screen, with rather limited success, it havin been found extremely diiilcult to make a device which could be readily shifted from time to time and which when so shifted could be depended upon to accomplish segregation.

The objects of the present invention are:

To provide a simple and ellicient structure.

adapted to seat against the interior surface of a well screen and outline an area of such screento becleanedr v s b To provide means for shifting thedevice into contact with the screen and for forcing it into sealing contact with and withdrawing it from the so I To provide means for compelling liquid supplied to the device and pulsated to flow alternately outward and inward through definitely restricted screen areas into and from the surrounding strata:

Toprovide means for shifting the devicelongitudinally of or laterally around the screen to permit positioning d contacting:

To provide a device for segregating screen areas adapted to be secured to the lower end of a we string, for shifting and'operation; v

To provide a device of the character described which is' eflective to segregate diametricallyopposite screen areas concurrently. and operate concurrently thereon.

The means by which the foregoing and other objects are accomplished and the method of their accomplishment will readily be understood from v the i'ollowinl specification upon reference to the accompanying drawings, in which:

Fig. 1 is a vertical sectional elevation of a well screen in place in a well with'screening aggregate therearound, showing a face side of the cleaning pparatus in-elevation. 1

Hg. 2 is a fragmentary side elevation on a re- 1'18. 3 is a sectional side elevation of the apshown in section only and thesegregating chain-- bersr'et'racted from the screen.

tion taken on the nne-vv ct Fla. 4.

' Fig. 6' is a sectional-plan taken on the line' VI-Vlof Fig, 3.

The device is for, use with a well string' includ 7 ing pumping apparatus and a discharge column In its preferred form, thedevice comprises a pair of open face chambers, each preferably a shallow box ll, each having shallow side walls ll, endwalls II, and a bottom or. back wall is,

vertically disposed. -Conformingly secured around. the periphery of, theopen outwardlyi'aced front of each box, or

being entirely open on the top or front. The bottom wall ll of each is provided with 8 slot of its length, These boxes are stood on end bottom toward bottom, so that their open tops or fronts face outward, and the bottom slots are chamber, respectively, is a continuous contacting member or gasket. of soft rubber. the outer edge-ofthis gasket in plan, alongthe pper and lower ends of the box, arcuately conforming to the curvature of-the well screen 28 with whichit is to be used, and along the sides being straight to likewise conform along vertical lines. The boxes are disposed in diametrlcallyopposed relation, with the gaskets carried-thereby, outwardly faced and with the slots in the backs vertically and inwardly Secured to the backs ll of the boxes as by welding, a're vertically disposed pipes '21, each pipe being closedat its bottom. end and slottedv to conform to the slot in the related box, the

welding sealing the pipes to the boxes around I their respective slots. The two pipes extend upward insubstantial parallelism to and are connected into the closed end it of a well pipe II duced scale showing a modified-form oi the device.

through which liquid, as water or oil, may be with:

drawn in usual manner, as by pump ns mach-- anlsm 3|, or be released to surge increase flexibili y. one (or both) of thel lle may include a flexible will"!!! -4.

ll is a well column which extends tothe ground surface. the structure serving also to raise and lower or turn the device in the well. The two P pes 21; are spacediapart to permit insertion therebetween of a pair of'spa'ced pins ll which paratusatrlghtanaleatol'ig. 1,-withthescreen eil'ect a cam member and are carried by abell extending to and discharging above ground level.

, link I reacts to effect boxes by the cammingac on of the spaced pins.

crank lever. 35, this lever preferably including duplicate arms l-A,18-B,' disposed on opposite sides of the pipes 21 and connected together by I the pins as between the pipes. The arms, fl-A,

"-13 extend laterally outward from the pins" third pin a link 38 extends upwardly alongside one of the pipes 21 and terminates in a ball ll to which is connected a cable 43 extending to an accessible point about the surface of the ground. Preferably the upper end of the link 39 is guided, as by abracket 4i conveniently secured to one of the pipes 21.

The diameters of the pins 33 and sizes of the pipes 21 and projection of the boxes l3 and their ent material 48 are secured at their upper ends on opposite sides of the. tube 29 and extend downwardly to and are secured at their lower ends toione of the pins 33, being here shown as connected to the upper of such pins. This connection serves not only to secure and brace the and are connected by a third pin 31. From this the screen area, the bowed members I! hold the boxes properly centered transversely to the direction in which they are to be moved apart.

The device having been positioned opposite to screenareaswhich are to be cleaned the cable 4} is pulled upwardly and through the bell crank lever 35, shifts the pins 33 from positions vertically, one above the other, out of such alinement, forcing the pipes 21 apart, and through this movement forcing the gaskets. 23 into sealing contact with opposite screen areas, thus outlining andsegregating screen areas for treatment. Thereafter the pumping mechanism may be started up to draw liquid violently inwardly from the surrounding strata through the segregated screen areas and stopped or even reversed to cause discharge outwardly through the same areas by pressure of the liquid in the pump column or direct reversed pumping action. This surging action is continued until cleaning of the areas is accomplished, pumping to discharge being run from time to time to determine by showing of detritus in such discharge. progress of the cleaning.

lower ends of the bowed flat members or guides,

but the guides through the pin connection. serve to support the bell crank member 3! and provide a fulcrum against which the pull of the reading apart ofthe screen is covered by each box so that full clean- While the preferred type of structure includes a two chambers which are moved apart by the camming action, it will be understood-that one only of the chambers II and tubes 31 may be used, or as shown in Fig. 2, a similar single chamber Il-A may be used, mounted on the lower end of the well pipe "-A and the chamber be displaced laterally by action of the camming member carried by the bell crank lever II-C, against-the well screen fl-A, such actionalso laterally displacing the well pipe "-A, and the well string thereabove.

It will further be understood that the details are largely introduced for the purpose of illustration and may be varied from except as in a claim specifically set out.

To use the device the pump column and pumping machinery carried thereby is removed from the well and usually, though not necessarily, to eifect saving in wear and tear on the regular pump, the pumping mechanism is replaced by a more rugged pump better adapted to cleaning purposes.

The present device is securely coupled into the lower end of the pumping mechanism and by means of the well column is lowered into the well until the boxes or chambers ll overliea section of the screen which is to be cleaned, this usually being at either the extreme upper or extreme lower end of the screen and more conveniently being at the lower end in order that the apparatus may be lowered until it seats and thereafter be progressively moved upward as cleaning progresses until the usually known length of screen has been covered, or until the boxes, eventually seating inside the solid well casing, indicate by stoppage of well discharge that such position is reached.

In this movement into the screen area.

. operation.

ing of a horizontal belt may be accomplished by two or three shlfts,as the case may be. After the first area belt is cleaned, the apparatus is released, and raised or lowered. as the case may the operationsrepeated, until the entire screen area has been'covered,,after which the device isremoved from the well, the regular'pumping apparatus replaced and the well is again put in a pair of pipes secured to, opening into, and extending downwardly from, said string, each pipe respectively carrying adjacent its lower end one of said chambers and opening thereinto, to pcsitlon said chambers relatively to said-' string and form passageways between said string and said chambers, said chambers being held by said pipes with their. open faces facing outwardly toward substantially diametrically opposite screen areas, each of said chambers having around its open face a gasket having a screen contacting surface of shape conforming to the periphery of its said screen area, and meanscarrled by said structure manually operable to shift said chambers apart to effect sealing contact of their respective open faces with said opposite screen areas, said means including a cammingmemberdis'posed in part between said pipes, and having a laterally extending portion,

and operating linkage pivotally secured to said v cxtendingportion adjacent the outer end thereof, and extending upward along said well string to the ground surface.

2. .In apparatus for cleaning the screen of a well, a structure including a well strlng supported from the ground surface, and pumping operatively connected therewith, a pair of open faced chambers disposed below said string, a pair of pipe-like members secured to and extending downward from said string, each of said members respectively being rigidly secured adjacent its lower end to one oi said chambers and opening thereinto, said members positioning said chambers below said string for coordinated movement therewith, said members opening into said string and forming passageways between said string and said chambers, said chambers being held by said members with their open faces facing outwardly toward substantially diametrically opposite screen areas, each of said chambers having around its open face a gasket having a screen contacting. surface of i6 shape conforming to the periphery of a said screen area, means carried by said structure manually operable to shift said chambers apart to eflect sealing contact of their respective open faces with said opposite screen areas, said means including a cammin'g member disposed in part between said members, and having a laterally extending portion, and an operating member pivotally secured to said extending portion ad- Jacent the outer end thereof, and extending upward alongsaid well string to the ground surface; and tension means oppositely secured to said chambers acting to withdraw said chambers from screen contact.

NORRIS E. GUNDERSON.