US2008871A - Nozzle - Google Patents

Description

0. F. MARVIN July 23, 1935.

NOZZLE Filed Feb. :5; 1950 U Tia. 4+

VENT OR (T/Wary? ATTORNEY I N Orr/n Patented July 3 9 UNITED "STATE PATENT OFFICE This invention relates to a nozzle, such asmay be used for d-irecting a 'stream'of fluid. Ingeneral, my invention can be utilized wherever there is a discharge orifice fora material that tends to Wear the Walls of the orifice. 1 Y

More particularly, my invention relates to a structure whereby the useful life of such'orifices (as fluid directing means) may be very materially lengthened, and especially by the use of a material forming the orifice that is so hard as to resist wear. Such a structure is useful for example for sand blast nozzles, which direct an abradent stream of air and sand against objects to be abraded. The sand, reaching a velocity in the orifice of such value, due to the impelling action of the compressed air, of course rubs against the walls of the orifice. If no special precautions be taken, the orifice soon enlarges to an extent making it unfit for use; and'in fact, the walls of the nozzle may wear entirely through.

Such action is also noted in nozzles that are utilized for other moving material, such as oil from a well, in which enough coarse sand exists to form quite an abrasive fluid, tending to wear out the nozzle.

It is one of the objects of my invention to M provide a nozzle structure in which this wear is minimized, so that nozzles may be used, under the right conditions, for as much as several thousand hours.

It is of course possible to choose that material for making the nozzle which resists wear best; but often such material has other qualities that interfere with its use as a nozzle. For example, tungsten carbide might be suggested frqmwhich a nozzle can be fashioned. This material is extremely hard and resists wear; but it is likewise very brittle, making it entirely unsuitable, by itself, as nozzle material.

It is therefore-another object of my invention to make it possible to utilize such material as tungsten carbide for forming the orifices of nozzles. I attain this object by providing a support for the orifice forming material in such a manner that the combined structure resists breaking.

My invention possesses many other advantages, and has other objects which may be made more easily apparent from a consideration of several embodiments of my invention. For this purpose I have shown a few forms in the drawing accompanying and forming part of the present specification. I shall now proceed to describe these forms in detail, which illustrate the general principles'of my invention; but it is to be understood that this detailed description is not to be takenin a limiting sense, since the scope of my invention is best defined by the appended claim.

, Referring to the drawing: 1

'Figure l is a part section, part elevation, of a nozzle structure embodying my invention;

Fig. 2 is a sectional View, taken along plane- 22 of Fig. '1; V Fig.3 is a sectional view, taken along plane 33 of Fig. 1; and Fig. 4 is apart section, part elevation, of a nozzlemember of slightly different form.

In Figs. 1, 2, and 3, I show a nozzle member I I, of general cylindrical form. This nozzle member is joined to an inlet pipe 12, to which a hose can be connected, and which has shallow vanes or ribs l3 for facilitating the tightening of the hose onto the pipe 52. tightlyconnectedto' the lower end of member II in any suitable way; for example, by a structure similar to a pipe coupling.

Thus a nut member 14 is shown as in threaded engagement with the upper threaded end of pipe I2 and it has a tapered aperture l5 therein coacting with a sloping shoulder on member II. By tightening coupling nut [4 it is apparent that the member H and pipe l2 will be drawn together. I

A lining tube I6 is shown in member II to define the nozzle orifice; this tube can either be made as a solid member or in sections axially spaced. This tube is preferably made from such hard material as tungsten carbide, to lend long life to the'nozzle. This lining or leeve is first made, and the outer member I l is'placed around. it to serve as a heavy support or cushion to hold the sleeve I6 against breakage. For example, member I I can be made from some comparatively softer metal melting at a much lower temperature than the material from which tube I6 is made. Thus such metal can be cast around the tube i6 and upon cooling, the member II will of course hold tube I6 tight. To ensure against any possibility of relative axial displacement, the outer member H can overlap the ends of sleeve or lining It, as shown at I! and [8.

Other material could be used for member H, such as vulcanized rubber, so long as it is massive enough and can serve effectively to prevent the sleeve 16 from being flexed to the breaking point. i As the nut M is tightened, the lower end of the lining [6 contacts with another wear resisting inset l9, which is placed into the top of pipe member H2. The upper end carries a reduced portion 20 which interfits in the overhanging shoulder l8 The inset 19 also has an aperture This pipe is arranged to be molds to form the linings or insets.

cooling.

2| that is oi the same size as the orifice of sleeve I6 and in fact forms a part of the orifice. This inset can be loose in pipe I 2, it being wedged downwardly onto a sloping seat 22 in the pipe. Furthermore, the aperture 2| widens at the bottom for the inlet of a stream of fluid.

This inset I9 can also be made from such material as tungsten carbide to protect the nozzle holding pipe l2 against wear. Other suitable material, not quite so hard as tungsten carbide, could be used, such as any of the common chromium, tungsten and manganese alloys. If such softer material is used, the inset l9 would have to be replaced quite often, such replacements be ing simple and inexpensive. The inset increases the effective length of the orifice, which can thus be chosen to be the optimum for the fiuid pres sure used, by proper choice of length of the inset. Thus the effectiveness of the abrasive stream (if the nozzle is used for sand blasting) is increased, due to the increased velocity obtained for the stream.

The members l6 and I9, which are preferably made from tungsten carbide, of course should be made from material that is free from pores or blow holes. In this way, the members do not crumble under use. To make it possible to produce tungsten carbide having no pores of appreciable or material size, it is preferred to pour molten tungsten carbide into massive copper conducts the heat away rapidly from the molten alloy; Copper isinactive in connection with tungsten carbide even at the high temperatures attained, and thus no gases are formed during A dense, tough grain structure free from pores is the result.

This manner of manufacturing tungsten car- The copper bide is the subject matter of another application filed concurrently herewith in my name, and entitled: Process of manufacturing tungsten carbide.

The nozzle holding parts, such as l2, l4, can be made from any desired kind of material, such as cast iron, machined to fit the parts accurately. A flange 23 can be provided at the base of the threaded part of member 12, to serve as an abutment for the hoseconnected to the pipe [2. The exterior sur facefof, member [1 can also be mashined, to form a valve fit with the nut Id.

In Fig. 4 I show an alternative form of nozzle structure. In this case, the inset or sleeve 24 is wedge shaped, the larger end being at the bottom. Thus the pressure of the fluid entering the base will tend to wedge the inset or lining 24 into the casing member 25. For this reason, no overhanging shoulder such as [8 in Fig. 1, is needed'to prevent axial displacement.

' I claim: 7

n a n zz es u ture, un s n carbide ea s. iorjfor ninga dischargeorifice, a nozzle support engaging said means, a shoulder on said support, a nozzle holder havingthreads thereon, an interchangeable inset adapted to be wedged in said holder and also adapted to be a continuation of said discharge means, said inset beingjwedged in said holder at an endcf the holder nearest said discharge means andsaid inset extending through said holder in a direction receding from said discharge means, and a nut. cooperating with said shoulder and said threads to urge said holder and said support together, thus wedging the inset tightly in said holder and holding it tightly against said means.

. ORRIN F. MARVIN.

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