US1974967A - Distribution method and apparatus - Google Patents

Description

Sept. 2.5, 1*!934. H, E, MCRERY 1,974,967

DISTRIBUTION METHOD ANT) APPARATUS Filed March 19 1952 5 Sheets-Sheet l Sept. 25, 1934. H. E. MCCRERY DISTRIBUTION`ME'IHOD AND APPARATUS Filed March 19, 1932 5 Sheets-Sheet 2 SWL, 25; 1934 H. E. MCQRERY www? DISTRIBUTION METHOD AND APPARATUS Filed March 19, 1932 Y 5 SheetsSheet 5 uuuu uuuu'uuuuuuuu'uuu 6.9

Patented Sept. 25, 1934 PATENT orties' DISTRIBUTION METHOD AND APPARATUS Harold E. McCrery, Pittsburgh, Pa., assignor to BlaW-Knox Company, Blawnox, Pa., a corporation of New Jersey Application March 19,

11 Claims.

My invention relates in general to the distribution of solids suspended in iluid streams and, in particular, to a method and means for obtaining a uniform distribution of abrading particles carried along in a blast of gas, usually air. Although 4the invention is described in detail hereinafter with reference to its application to va method and apparatus of blasting, it is not limited to such application.

In the art` of blasting as practiced heretofore and, particularly, the art of blasting metal sheets or plates for removing the scale therefrom, it is known to supply abrasive particles to an air stream, and to sub-divide the stream in order to extend the abrasive effect thereof over a considerable area of the sheet or plate under treatment. Great difliculty has been encountered, however, in obtaining a uniform distribution of the abrasive material over the desired' eiective 30 distributing solid' particles carried along in an air stream for the purpose of cleaning metal surfaces for'galvanizing, welding or other treatments which insures a uniform distribution of the abrasive material and, therefore, a uniform effect upon the' metal being cleaned. In accordance with one Iform of the invention, I arrangel the supply conduit as a'vertical riser and take oiI' the sub-divided passages from symmetrical points therein. These sub-divided passagesmay' thereafterbeinclined to any 'desired' angle'without substantially affecting the uniformity vof distribution of abrasiveparticles in the'jets issuing from nozzles at the ends of the passages.4 The' invention provides uniformity of abrasive or blasting effectY because, in a vertical riser, there' isv a random distribution of the particles 'in the air. stream,` that is, each Vunit volume of air, on the average', contains the same number of abrasive particles'asevery other unit volume. y Iny another form of thev invention, itis not' necessary that the supply conduit bea `vertical riser." In accordance therewith, the abrasive particles in a supply conduitare separated' by a vertical plane' and delivered to two sub-divided pas'- sages. Even in a horizontal' supply conduit, the

1932, Serial N0. 599,948

distribution of solid particles is symmetrical about a vertical diametrical plane. Itis thus possibieto obtain equal distribution of abrasive' particles between two sub-divided passages if a vertical dividing plane is employed. The application of this principle may be' carried to any desired extent, each of the first sub-divided passages being again divided by vertical walls .to further. sub-divide the stream into a plurality of branches. The number of branches ultimately employed depends upon the number of nozzle jets desired for covering the area to be treated'.

The second form of the invention may also be employedV to advantage in connection with the' first form between the symmetrical offtakes from' the vertical riser and the nozzle jets proper.

For a complete understanding of the invention, reference is made to the accompanying' drawings illustrating a present preferred embodiment. In. the drawingsz- Figure l is a side elevation with parts-'in section of an apparatus for practicing the invention;

Figure 2 is an end View'of the device shown in Figure l taken substantially along the line II-II thereof;

Figure 3Y is a sectional View along the plane of line III-III of Figure 1; Y

Figure 4 is an elevation to enlarged scale of a portion of the apparatus shown in Figure 1,. with a part in section and parts removed; l

Figure 5 is asection View along the plane of line 'if-V ofl Figure 4';

Figure 6` is a sectional view along the plane of' line lVI--VI of Figure 4;

.Figure 7 is a plane View of a nozzle plate; v

.Figure 8 is a diagrammatic side elevation ofy the invention in association with means for'conveying a plate therebelow;

Figure 9 is a similar view showing a diierent type of. blasting apparatus; Y

Figure 110 is a partial plan View of the apparatus as shown in Figures 8` and 9;Y

Figure l1 is another View showing the appara-` tus for cleaning both sides of a metal plate simu-lhtaneously;

Figure 12 is a View similar to Figure '7'Y showing amodi-ed form of nozzle plate; and t Figure 1-3' isasection View along the'line XIII- XIII 0f' Figure 12'.- f,

Referring now in detail to the d'ravvirigs and, for the present, particularly to Figures I through '7, the apparatus forpracticing the i'nv'eTitien` comprises a vertical supply conduit 10 which isAA preferablyr provided with Lani'nn'er tube 1`1` ther`e' in. A ring 12spaces the tube 1'1 from the conduit 10. A distributor head 13 rests on the conduit 10 and is provided with a plurality of diverging passages 14. These passages are slightly tapering in cross section and are symmetrically disposed with respect to the axis of the head and the conduit 10. A multiple passage elbow 15 is secured to the head 13 by bolts 16 and the head and elbow as a unit are connected to the conduit l0 by stud bolts 17 traversing a flange in the elbow and a flange screwed on to the conduit 10. The elbow 15 includes a vertical portion 18 and inclined portions 19 and 20 integral therewith. Axial passages 21 are bored through the vertical portion of the elbow, the upper ends of which are closed by plugs 22 forming clean-out ports. Inclined passages 23 are bored in the inclined portions 19 and 2G of the elbow and intersect the passages 21.

Multiple passage conduits 24 and 25 extend upwardly from the inclined portions 19 and 20 of the elbow 15. The conduits 24 and 25 have a plurality of axial passages 26 therein registering with the passages in the elbow. Therconduits 24 and 25 extend through a closure 27 in the wall of a blasting machine. Brackets 28 and 29 extend from flanges on the conduits to the closure. A nozzle head 30 is carried at the upper ends of the conduits 24 and 25. Elbow portions 19 and 20, conduits 24 and 25 and the nozzle head 30 are suitably flanged for connecting bolts, which are omitted for the sake of clearness of illustration.

The nozzle head 30 is shown in detail in Figures 4 through 7. The nozzle head comprises a casting having tubular portions 31 and 32. These portions are bored to provide passages 33 registering with the passages 26 in the conduits 24 and 25. The passages 33 to the left of the central longitudinal plane passing through the head 30, as shown in Figure 5, are connected by passages 34 and 35 at right angles thereto, to nozzle ports 36. Similarly disposed passages 33 in the tubular portion 32 of the head have passages 37 and 38 connecting them to similar nozzle ports. Passages 39, 40, 41 and 42 likewise connect the passages 33 on the other side of the vertical longitudinal plane to respective nozzle ports.

As stated, the nozzle head 30 is a casting and the passages therethrough are preferably formed by tubes 43 cast integral therewith.

Nozzle plates 44 having aligned nozzles 45 are removably secured to the nozzle head by yokes 46 and set screws 47. The yokes 46 embrace securing lugs 48 on the nozzle head and attaching lugs 49 on the nozzle plates. Depressione 49a in the lugs 49 are adapted to receive the ends of the set screws 47.

As is obvious from Figure 6, the nozzles connecting with the several multiple passages are spaced apart uniformly longitudinally of the nozzle head so that the head, including eight nozzles, is effective to direct abrasive blasts of uniform intensity against an extended area of a plate or other article positioned adjacent the nozzles.

Referring now to Figures 3 through 11 showing methods of applying the apparatus above described to blasting methods, Figure 8 shows a set of three nozzle heads 50, 51 and 52'similar to the head 30, disposed in side-by-side relation and offset laterally with respect to each other so that an area of considerable width is covered by the jets from the nozzles carried by the heads. Inclined shafts 53 and 54 carry supporting rolls 55 and 56 for conveying a sheet or plate 57 beneath the jets from the nozzle heads for cleaning the surface of the sheet. The latter is disposed in an inclined position so that the blasting material and the scale cleaned from the sheet will slide off the surface thereof and no brushing or wiping means will be necessary. The side-by-side and laterally offset relation of the nozzle heads may be more clearly observed in Figure l0. Figure 9 shows a set of nozzle heads 58,59 and 60 arranged similarly to those of Figure 8 except that they are in a horizontal instead of an inclined plane.

Figure il shows a similar arrangement in which nozzle heads 61, 62'and 63 for cleaning the upper surface of a sheet are supplemented by nozzle heads 64, 65 and 66 disposed below the sheet for cleaning the bottom surface thereof. In Figures 9 and 11, conveying rolls 67 on shafts 68 are illustrated as typical conveying means for moving the sheet shown at 69 past the blasting nozzles. Guide rolls 7) may be employed also.

In the form of the invention heretofore described, a vertical supply conduit is essential because otherwise a random distribution of abrasive particles in the air stream is not obtained and it is only by symmetrically sub-dividing a supply stream in which the particles have random distribution that it is possible to provide a plurality of small jets of uniform intensity. It is also possible to obtain this result by another means. Figure 12 shows a nozzle plate similar to that shown at 44 in Figure 7. The nozzle plate of Figure 12, designated at 71, however, has a pair of discharge nozzles 72 for each inlet port 73. The individual stream supplied to the port 72, therefore, is divided into two smaller streams each having an equal percentage of abrasive carried thereby. This type of nozzle plate presents certain advantages for use in connection with the nozzle head and distributor head already described, but also indicates that an air stream may be divided into separate streams having the same amount of abrasive if the main stream is divided by a vertical plane. It is thus possible to avoid the necessity of having a vertical riser serve as a supply conduit. A horizontal supply conduit, for example, could be provided with means for dividing an air stream passing therethrough along a vertical plane, Each of the resulting streams could be further sub-divided and the process carried to any desired extent to provide a plurality of individual jets, each having the same amount of abrasive and therefore equally effective in cleaning a metal surface.

It will be apparent from the foregoing description that the applicant has provided a very simple solution for the heretofore difficult problem of obtaining a uniform distribution of abrasive material in a plurality of branches leading from a main supply conduit. Y

Although Ihave illustrated and described herein but a single present preferred embodiment of the invention, together with a modification of a portion thereof, it is not limited to such forms of apparatus but may be otherwise embodied yand practiced within the scope ofthe followingclaims with all the advantages and benefits mentioned..

I claim: f

1,. In an apparatus for uniformly distributing solid material carriedby a fluid stream, the com-, binationwith a vertical supply conduit of sub- L stantial lengthwhereby random distribution of said material occurs therein, of a plurality of in- 2. Distributing apparatus for a mixture of fluid and solids comprising a supply conduit extending substantially vertically, a distributor head on said conduit at the upper end thereof, having a plurality of individual passages arranged symmetrically about the cross-section of the conduit, and a multiple passage elbow having passages registering with those of said head, connected to the head for conducting individual streams of fluid and solids to their points of application.

3. In an abrasive distributing apparatus, the combination with a supply conduit disposed substantially vertically, of a distributor head closing the upper end of said conduit, said head having a plurality of individual passages therethrough disposed symmetrically about the cross-section of said conduit, and an elbow having passages registering with those of said head for conducting abrasive to its point of application.

4. In an abrasive distributor, a supply conduit arranged substantially vertically, a distributor head on said conduit at the upper end thereof having a plurality of individual passages disposed symmetrically about the axis of said conduit, a multiple passage elbow on said head having passages registering with those of the latter, and a nozzle head having passages registering with those of said elbow and spaced longitudinally of the head to provide a plurality of abrasive jets effective over a substantial area.

5. In a method of handling solids carried in a fluid stream, the steps including conducting the stream substantially vertically upward and maintaining a uniform distribution of solids therein, sub-dividing it symmetrically about its axis while its upward ow is maintained into a plurality of smaller streams, and conducting said smaller streams to points of use.

6, In a method of uniformly distributing abrasive material carried by a fluid stream, the steps including conducting said stream substantially vertically and maintaining a uniform distribution of solids therein, sub-dividing it symmetrically about its axis, and conducting the sub-divisions of said stream to laterally aligned points of use.

7. In a method of blasting, the steps including directing a stream of fluid carrying a solid substance vertically, maintaining a uniform distribution of the solid in the stream, sub-dividing the upwardly moving stream symmetrically about its axis while its upward flow is maintained and conducting sub-divisions of the stream to points of use laterally aligned in a common plane.

8. A method of distributing solid material carried in an air stream including the steps of directing said stream upwardly to produce a random distribution of said material therein, and subdividing said stream while maintaining its upward direction of flow to produce a plurality of smaller streams having substantially the same portion of solid content.

9. In an apparatus for uniformly distributing material carried in a fluid stream, the combination with a substantially vertical supply conduit of substantial length to obtain random distribution of material therein, of a plurality of passages branching from said conduit and disposed symmetrically about the cross-section thereof, and nozzles communicating with said passages to form jets carrying substantially the same amount of material therein.

10. Inan apparatus for uniformly distributing matter carried by a. uid stream, the combination with a vertical supply passage of substantial length whereby to obtain random distribution of the matter in said stream, of means for dividing said passage symmetrically of its cross-section into a plurality of separate passages.

11. A method of uniformly distributing solid matter suspended in a fluid stream comprising maintaining random distribution of the matter in a substantially vertical stream of fluid, dividing the stream symmetrically about its axis into a plurality of smaller streams and while maintaine ing the direction of travel of the streams substantially the same, and conveying said smaller streams to a point of use.

HAROLD E. MCCRERY.

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