US1657130A

US1657130A - Screen pipe with slots disposed in circular areas

Info

Publication number: US1657130A
Application number: US110276A
Authority: US
Inventors: Jr Joseph Henry Mcevoy
Original assignee: Individual
Current assignee: Individual
Priority date: 1926-05-19
Filing date: 1926-05-19
Publication date: 1928-01-24
Anticipated expiration: 1945-01-24

Description

Jan. 24, 1928.

J. H. M EVOY, JR

SCREEN PIPE WITH SLOTS DISPOSED IN CIRCULAR AREAS Filed May 19. 1926 1% 2 JNT/ENTOR JOSEPH /7c 5/ Patented Jan. 24, 1928.

UNITED stares insane PATENT OFFICE.

Josnrn' nanny MQEVOY, :rnjor nousron, TE

SCREEN PIPE WITH SLOTS 31 Application filed May 19,

This invention relates to oil well equipment and it particularlyrelates to a screen pipe adapted tloruse in an oil well. i

In the production of oiland gas from wellsit is common practice to use what is known as an oil string of pipe, this string extending down through the well casing into the oil bearing stratum. was for rnerly the practice to drop the oil'sting in place in the oil bearing stratum and'then to perforate it from-the inside by means of a periorator, this pertorator producing; openings in the pipe through which the oil flowed into theainterior of the well. the oil being removed from the well either by means oi a pump or by natural flow. l Jhen the oil string was so perforated the openings produced, whether inthe tornioit' round holes or slots, were unsatisfactory inasmuch as they could not be perforated in small sizes, this resulting in the admittance oi": sand and gravel of considerable site into the well which tended to interfere with the operation thereof. It has, therefore, become standard practice to perforate the lower end. of the oil string before putting it in place in the well and it has been found that it is desirable to perioratethe oil string with thin elongated slots, these slots acting; as a screen and excluding coarse sand and gravel from the Well. It has been found, however,

that if a suiiicient number of openings to freely admit oil is provided the screen pipe, as it is denominated, is considerably weal:- ened, both against longitudinal stresses and against forces tending to twistor collapseit. I have found that by grouping the slots closer together than in usual practice and confining; thorn into definite areas the capacity oi the screen pipe is not reduced, but the strength thereof is cmisiderably iiu creased.

it is accordingh an object of this intention to provide a screen pipe in which the slots therein are grouped together in definite confined areas for the purpose of giving strength to the pipe. j

it is readily apparent that the greater the distance between the diil'erei'it groups or slots, the greater will be the strength of the pipe. I have found that by grouping the slots in confined circular areas that greater distance may be provided between the different groups with but a small sacrifice of capacity.

It is accordingly another object of this srosnn Lari crricunen Anna's.

1926. Seriai No/11037G.

inyention to provide a screen'pipe in which the slots thereinare groupedin definite cir lustrate this invention p y c Fig. lis a diagrammatic view illustrating one utility of my invention.

2 is atragnientary plan View; showing clearly the inanner in which the slots screen pipe of my invention are located. Fig". 3 is a section taken on the line 3+3 oi Fig. 2. y 5 is a fragmentary View illustrating the spacing of the slots in tin-ordinary screen p ll .I. i i

in the drawings, 11 represents the tloor ot a derrick which is situated over a well 12 which is provided with a string" of well casing; 13 which extends down to apoint just above the oil be aring stratum i i. The water string or well casing 13 may be cemented, as shown at 17,to shut out surface water. Extending into the Well is a pipelS which is commonly termed an oil string. L ,he lower end oft-he oil string 18 is provided with a screen pipe 19 of my invention which extends through the oil bearing stratum 14', as illustrated in Fig. 1. Extending into the oil string 18 is a puniptubing 21 which e1:-

tends through a casing head 22 connected to the upper end of the oil string18 above the derrick floor 11. Near the lower end of the, well 12 there is an oil well pump 23 which is connected to the lowerend fot the pump tubing 21 and by means of which oil is elevated to the surface of the grounds The screen pipe 19 which incorporates the tea tures of iny, invention is provided with. groups of slots 25 ,which are separated by impertoratebridges 26. i

The" construction of the clearly illustrated in l i H groups of slots iuclu elongated and narronwslcts27 which, as illustrated inFig; 3,1nay be keystone or wedge-shaped for the purpose of giving relief so that there will be but the reniotest tendency for them to clog. The slots 27 of each group 25 (Fig. 2) are of different lengths. These slots 27 are so proportioned that they are situated inside a definite circular area. In other screen ,

pip e

2 and ,3. The

Referring to the drawings in which I ilcular areas, a very wide bridge 26 is formed between each group of slots. It should be noted that a much wider bridge is provided by confining the slots in circular areas than would be possible if the slots were grouped in square areas. In Fig.2 dotted lines 31 represent square areas. It will be seen that the same grouping of slots in square areas would reduce the size of the bridges very greatly and a screen pipe having slots grouped in square areas would lJB WGMKQI than the screen pipe of my invention hav ing the slots grouped in circular areas. is, of course, apparent that the capacity of the screen is reduced a little, since certain oi. the slots of each group must be shorter than the longest slots of the group. It will be seen, however, that but very little ofthe screen capacity is sacrificed by shortening some of the slots of each group.

In Fig. 4; I illustrate a portion of the screen pipe having elongated slots 36 formed therein. according to standard practice. These slots 36, as illustrated, are not confined to definite areas or arenot grouped; there are, therefore, no actual bridgesprovided between the-slots. In the ordinary screen pipe, as illustrated in Fig. 4, each slot is spaced a definite distance from the next slot, the slots throughout the entire length of the screenpipe being of substantially the same spaclng.

In my invention I group the slots, placing the slots of each group closer together than the slots in anordinarycasing and-provide imperl'orate bridges 26 which are quite large and which give the screen pipe con siderable strength. Comparing Fig. 2 with Fig. l it will be seen that in the screen pipe of my invention 1 group seven slots into a coinparatirely small area as compared with the area occubiedby the seven slots in the screen pipe shown in Fig. 4-. By placing more slots in a given area, as illustrated by the comparison between Figs. 2 and 4-, I am enabled to produce asereeu pipe having substantially the same capacity as an ,ordi nary screen pipe, luit onewhich has inuch more strength becauseof the ilnperforate bridges 26. d

It is quite important that the screen pipe have considerable strength to withstandany stresses which may be placed thereon. For

example, referring to Fig. l, the oilbearing stratum 14: is shown in an inclined extension, this being very common in such formations. When the oil bearing stratum is at an inclination there is more or less shifting thereon. It the strainer pipe is not very strong and is unable to resist the stresses imposed thereupon by the shifting formation,

it will undoubedly be collapsed. For this reason it is sometimes practice not to pro vide the ordinary form of strainer pipes with even as many slots as shown in Fig, l. It will be quite evident that the screen pipe of my invention will have much greater strength than the ordinary screen pipelincause ofthe grouping of the slots to provide bridgesQG and will, therefore, better resist the stresses imposed thereupon while in a well.

As previously explained the bridges 26 are made larger by grou 'iiug the slots in circular areas and this is an important part oi? the invention. Although my invention Ill has a particular utilityyin the oil producing industry it should be understood that I may employ the idea in the construction of screens for other uses.

I claim as my invention:

1. A screen pipe having slots formed therein, said slots being parallel and grouped in confined areas so as to provide imperforate reinforcing bridges between each pair of adjacent groups, laterally disposed slots of each group being shorter than slots centrally disposed, to cause each group of slots to lit the boundaries of the area in which it is confined.

2. A screen pipe having slots formed therein, said slots being parallel and grouped in confined areas so as to provide reinforcing bridges between each pair of adjacent groups, laterally disposed slots of each group being shorter than slots centrally disposed, to cause each group of slots to lit the binindaries of the area in which it is confined.

3. A. screen pipe having slots formed in the material of the wall thereof, said slots being parallel and; grouped in confined areas cl a surface cl? said wall, the length of the slots of ear-h group decreasing progres sively from the interior to theextcrior or each group. H

In testimony whereo t, I have hereunto set my hand at I-louston, Texas, this it) day of lilay, 1926. it

JOSEPH HENRY MclEVOY, JR,

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