US2329157A - Well-treating tool - Google Patents

Description

Sept.l '4"flh943` .m w. FRAcK '2329557 WELL Tnx-:mina mor.. luna@ Apri; so.' i941 A T 'TORNEi/S.

Patente-d Sept. 7, 1943 Dow .Chemical Company Midland,Mich.'a

corporation of Michigan Application April 30, 1941,.

2 claims. (o1. 16e-2o) This invention relates to an improvement in a well treating tool adapted to deliver one or more high velocity streams or .jets of acid solution into a well bore against the face ofthe formation, well casing, or other parts of the Well.

, In treating wellswherein a tool is employed to direct a series of high velocity streams of acid .against various portions of the well bore, -it oftentimes happens that it is desirable to seal the orices through which the acid issues during the period the tool is being positioned at the desired location in the well bore. Placing a seal over the orifices is desirable in order to eliminate the possibility of sand, or mud entering the tool through the orifices and exerting a plugging action by becoming lodged in the small passageways through which the fluid passes. It is alsodesirable to prevent entry of fluid 'into a treating tool of this type since any uid which enters the tool must be forced therefrom through the ysmall orices therein, and as a result more time is required to complete a treatment. Such sealing means should, however, be readily removable after the treating tool has been positioned at vthe desired location in the `Well bore.

It is, therefore, the principal object of ths'invention to provide an acidY treating tool having sealing .covers for the orifices through which the acid solution isto be ejected, said covers being characterized by being readily removable after the acidizing tool has been positioned in the well Y bore at the desired location.

xshown issuing from the tool I and impinging against theface of the formation at5. f

In the more detailed View of Fig. 2 the housing 6 of the acidizing tool is shown connected atits upper end to a swage nipple 1 by means of coupling or collar 8. The reduced vend of nipple 'I is threaded for connection to the conduit 3 whichv may suitably be the Well tubing. At intervals the housing is provided Withplug members r9 which are attached to the housing as by welding. The plug members 9 are internally threaded for 1 threaded engagement with the orice members I through which the acid issues into the well bore.

In the enlarged detailed view of Fig. 3 an orifice member I0 is shown with a small orice or port I I centrally located therein. The orice I I is counterbored at the outlet so as to form anenlarged recess I2 into which a dome-shaped readily acid-soluble metal disk I3 is pressed to act as a seal for the orifice.

Other objects and advantages will be apparent as the description of the invention proceeds'.

The invention will be more readily understood from the following description taken in connection with the accompanying drawing wherein:

Fig. l is a somewhat diagrammatical elevational vieW of a well bore showing the tool positioned adjacent a section ofthe formation it is Y desired to treat.

n adapted to cover the orifice.

Fig. is a cross-sectional view taken along lines 5,-5 of Fig. 4.

As shown in Fig. 1, the acidizmgtom |v is suspended in the well bore 2 by means of a suitable conduit 3. High velocity streams of acid 4 are The dome-like shape of the readily acid-soluble metal disk will be more readily appreciated with i and upon coming intoV contact with the readily acid-soluble sealing disks will rapidly dissolve them so that the acid solution will have ready access to the Well bore. Pressure will then be applied to the acid to force it from the tool in high velocity streams or jets. The pressure employed may vary quite widely as from a few hundred upto 3,000 pounds per square inch.

The acid solution to employ will, of course, depend upon the use for which it is intended. In generaLwhen treating a producing formation or bringing about the disintegration of cement, hydrochloric acid or a mixture of hydrochloric acid and hydroiiuoric acidv will be employed. y

The readily acid-soluble metal sealing disks are most suitably made of magnesium metal. The term magnesium used herein and in the appended claims is intended to include the magnesium of commerce which contains small amounts of impurities such as iron, copper, and the like as Well as' alloys of magnesium in which 'this metal is the predominant constituent. Mag- '2,329,157 Y "Y I nesium is very readily soluble in most acids and is very rapidly dissolved by both uninhibited and inhibited hydrochloric acid.

The sealing disks employed for the purpose at hand may vary quite Widely in thickness. Generally illustrative of a suitable thickness is from 11g to 1A; of an inch. It has been found desirable t to form the disks so that theyl will have avdomelike shape schislisiiliustraedfisince .larger area will be 'r'rp'sed' to the action Yof the acid,

assuring more immediate and complete removalr A.

" housing into the Well bore, said plug members lhavingccunterbored recesses about the orifices,

of the sealing covers.

I claim:

1.v In a. Well treating tool vadapted yto deliver am I K high velocity stream of acid to'lthe'vv'eli'fbcrte, the combination which includes ahhusin'g' adapted'to.

be connected to the well tubing, plug members attached to the housing havlgoribes therenffl 5 plug members in sealing relation.

2. In a well treating tool adapted to deliver a high velocity stream ofy acid to a Well bore, the combination which includes av conduit, a housing aidaptefdto"bedconnectdto 'the "conduit, plug 1o members attached to saidhousing having orifices p therein through which acid may issue from the and dome-shaped magnesium metal disks engag- 'lngith counter-bored recesses in the plug mem'- ersfin' 'sealing feiation. MORRIS W. FRACK.

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