Nozzle

“ The undeniable fact is that the machine does operate, both expansively and impulsively. When the expansion in the nozzle is complete, or nearly so, the fluid pressure in the peripheral clearance space is small; as the nozzle is made less divergent and its section enlarged, the pressure rises, finally approximating that of the supply. But the transition from purely impulsive to expansive action may not be continuous throughout, on account of critical states and conditions and comparatively great variations of pressure may be caused by small changes of nozzle velocity. ”

“ A small hole is drilled almost, but not quite, through the nozzle. While the nozzle retains its initial shape and size the apparatus acts normally, but as soon as the small amount of metal covering the end of the hole has worn away, the hole is exposed, and a certain amount of steam passes through it to a steam whistle which blows continuously until a new nozzle has been inserted in place of the one which is now worn so much as to make it uneconomical in steam consumption. ”

“ Probably more patents have been taken out on new suction nozzles than on any other portion of a pneumatic suction plant. The chief desiderata for a nozzle on a high pressure system for wheat, coal, ashes, etc., are that it be of light construction to allow of easy manipulation by the operator, and that it have some means of allowing a “free air” inlet, making it impossible to choke the nozzle by burying the end. It is an advantage to be able to regulate the free air inlet according to the conditions existing with different materials. ”

“ A simple connecting nozzle, (2) a fine adjustment valve, or (3) a regulator. The first is seldom used in practice for lantern work, for the reason that the direct pressure of a full cylinder (120 atmospheres) cannot be checked or controlled by a tap on the jet, as the intervening rubber tubing would either burst or blow off, and must therefore be regulated at the cylinder nozzle itself, and gradually readjusted as the pressure diminishes. ”

“ So, remember that the nozzle has something to do with the power of the engine, and you can see why the fellow that makes his engine clean its own flues is not the brightest engineer in the world.
While it is not my intention to encourage the foolish habit of pulling engines, to see which is the best puller, should you get into this kind of a test, you will show the other fellow a trick by dropping the exhaust nozzle off entirely, and no one need know it. Your engine will not appear to be making any effort, either, in making the pull. ”

“ Each nozzle carries its own injector, so that the design is always suited to the conditions. While torches are made having the injector as a permanent part of the torch body, the replaceable nozzle is more commonly used because it makes the one torch suitable for a large range of work and a large number of different sized flames. With the replaceable head a definite pressure of oxygen is required for the size being used, this pressure being the one for which the injector and corresponding mixing chamber were designed in producing the correct mixture. ”

“ The Exhaust Nozzle, as generally constructed, is an elbow attached to the end of the exhaust pipe in the smoke box or smoke stack of the boiler, the end of which points upward, with the opening reduced so that the exhaust steam will be forced up the stack, and thereby produce the same effect as a blower. ”

“ An iron pipe, constructed with several flexible joints, leading from a blowing machine, is bent in such a way as to allow its nozzle end to be introduced within the retort, and directed to any point of its surface.
I should suppose that air, even at common temperatures, applied to a retort ignited to the pitch of making gas, would burn away the incrustations; but hot air will, no doubt, be more powerful. ”

“ When ignition has occurred, the pressure of explosion opens the nozzle valve F, allowing 86the compressed gases to flow through the nozzle G to the bladed turbine H, on which the energy is to be expended. The expansion of the heated gases in the nozzle reduces the pressure to that of the exhaust, with the resulting increase in the velocity of the gas. By means of fresh air, the nozzle valve F is kept open throughout the expansion and scavenging periods. ”

“ Air-pressure is admitted to the tank by a bottom valve, and forces the paint up an internal pipe and along a hose from the tank to the spraying nozzle, to which air-pressure is also led by a second hose. The nozzle is practically an injector of special form. The flow of paint at the nozzle is controlled by a small plug valve and spring lever, on which the operator keeps his thumb while working, and which, on release, closes automatically. ”

“ A brush flame is one which issues from the blow-pipe nozzle shaped like a brush, i.e. it expands on leaving the jet. It is produced by using a cylindrical air jet or a conical jet with a large aperture, say one-eighth of an inch. ”

“ The nozzle proper is made from copper, because it withstands the heat of the flame better than other less suitable metals. The torch must be built in such a way that it is not at all liable to come apart under the influence of high temperatures. ”

“ If the conveying plant is to be efficient and of reasonable capacity, the pipes must be relatively large, and in order that the desired partial vacuum may be maintained in them (establishing a vigorous air current) without the use of an unduly large pump, it is important that air be admitted only through those nozzles which are actually in use. Also, when more than one nozzle is in use at the same time, it is necessary to keep each nozzle covered with material to such an extent that the same amount of air passes into each pipe. ”

“ This cleaning is accomplished with a piece of copper or brass wire run through the opening, and never with any metal such as steel or iron that is harder than the nozzle itself, because of the danger of changing the size of the openings. The torch head and nozzle can often be cleaned by allowing the oxygen to blow through at high pressure without the use of any tools. ”

“ The power of the wheel is consequently increased or diminished to meet the change of load, and a constant speed is maintained. When it is necessary to waste as little water as possible, a concentric tapered needle may be fitted inside the nozzle. When the nozzle is [Pg 379] in its highest position the needle tip is withdrawn; as the nozzle sinks the needle protrudes, gradually decreasing the discharge area of the nozzle.
Pelton wheels are designed to run at all speeds and to use water of any pressure. ”

“ Therefore B1 has its convex, B2 its concave, side facing the reader, as it were.
The Nozzle is a 1-1/2 inch piece of brass bar. Drill a 1/20-inch hole through the centre. On the outside end, enlarge this hole to 1/8 inch to a depth of 1/8 inch. The nozzle end is bevelled off to an angle of 20 degrees, and a broach is inserted to give the steam port a conical section, as shown in Fig. 72, so that the steam may expand and gain velocity as it approaches the blades. Care must be taken not to allow the broach to enter far enough to enlarge the throat of the nozzle to more than 1/20 inch. ”

“ Three or four of us got there early and pitched in to help the firemen.” He had to shout to make himself heard. “I was up on the ladder, next under the nozzleman, holding up the slack of the hose. Well, sir, do you know the water kept dribbling down from the nozzle around my fingers until they were just about froze stiff. Finally, they let go—I couldn't help it, my fingers just straightened out. Then the slack of the hose fell and jerked the nozzle right out of the nozzleman's hands. ”

“ For this reason, the greater the lift the smaller the stream that can be thrown effectively, and the size of nozzle used should depend upon the height the water is draughted, reducing it one-eighth inch for every five feet above a lift of ten feet. If the engine uses a 11⁄4-inch nozzle for ordinary work, it will answer for any lift up to 10 feet. ”

“ Make a nozzle at one end of a piece of No. 2 tubing, make a bend near the nozzle, cut off the other end at such a length that it will reach to within 1⁄4 inch of the bottom of the bottle, smooth this end, allow it to cool, wet the tube and the two-hole stopper, shove it through one hole of the stopper, insert an elbow in the other hole, and your squirt bottle is complete (Fig. 55) . ”

“ The volume of gas drawn into the mixing chamber depends on the size of the injector openings and the pressure of the oxygen. In practice the oxygen pressure is not altered to produce different sized flames, but a new nozzle is substituted which is designed to give the required flame. ”

“ Shut the nozzle and valve-hole of a pair of bellows, and after having squeezed the air out of them, if they are perfectly air-tight, we shall find that a very great force, even some hundreds of pounds, is necessary for separating the boards. ”

“ The nozzles are placed at an angle of 20 degrees to the plane of motion of the buckets. The best energy in the steam is practically devoted to the production of velocity in the expanding or divergent nozzle, and the velocity thus attained by the issuing jet of steam is about 4,000 feet per second. ”

“ If the pressure is increased greatly the hose will burst; but, if the small nozzle be replaced with a larger one, the projection of the stream will be quite as great, but all undue tension of the pipe is overcome and the danger of bursting is done away with. ”

“ The nozzle of the blow pipe entering the center of the flame, and the cock being open, the liquid flows, and a column of white smoke descends vertically to the surface of the water, where it forms several concentric rings whose relief soon increases with the thickness of the heavy smoke, which finds no exit. ”

“ As the air pumps are set working a partial vacuum is formed within the tank, and as the nozzle end of the pipe is immersed into the grain to the depth of a few inches, the air and grain are drawn in at the mouth of the nozzle and carried along the pipe to the vacuum tank. ”

“ The diameters of the inlet and outlet nozzles are so nicely adjusted that, so long as both are at the same temperature, the outlet nozzle, which is open to the atmosphere, will pass all the air that the inlet nozzle can deliver without disturbing the pressure in the cistern, O; but if heat be applied to the circulating air through the walls of the spiral heater, the air expands in volume, and is unable to pass through the outlet nozzle in its heated condition as rapidly as it is delivered cold by the inlet nozzle. ”

“ If we only wish to ascertain the sign of the difference of the potentials at two places, and not its numerical value, we may cause drops or filings to be discharged at one of the places from a nozzle connected with the other place, and catch the drops or filings in an insulated vessel. ”

“ As they lift they get inflated with air; they are then sharply forced down on their own folds, and the contained air ejected forcibly through an iron or clay nozzle, into the very small heap of glowing charcoal which forms the fire. ”

“ By turning the bevels, the nozzle turns in the casing threads causing it to move back and forth for the adjustment.
In many types of burners having a nozzle similar to (15) a twisted form of rifling is placed in the bore that gives the escaping gas a rotary motion. This is very effective in mixing the air and oil vapor and spreads the flame very close to the orifice. In burners of the chamber type a spiral vane is sometimes used to gain the same effect, and in one make a rotating fan, is placed near the opening of the outer nozzle which gives a sudden whirl to the gases. ”

“ Compressed gas cylinders are painted a distinctive colour, oxygen for example being black and coal gas or hydrogen red; the screw connections to the pumps, and all nozzle {17}and regulator fittings, are made with a totally different screw and therefore cannot be interchanged; the cylinders themselves are bound by law to be reannealed and retested under hydraulic pressure at regular intervals; the steel itself has to be of a guaranteed quality; and, in fact, every possible risk is guarded against. ”

“ This globe is attached to the end of a line of hose, and the force of the stream causes it to revolve and distribute a number of small powerful streams in every direction. This is especially efficient when hung in a subbasement that is filled with smoke. There are also small sprinkling nozzles used to clear a smoky room.
The enormous force of a fire stream renders it a difficult matter to retain control, and many are the accidents reported of firemen who have been disabled by failing to hold the nozzle. ”

“ His first lucid thought was that he must unscrew the nozzle from the hose. Why, of course! How simple! But when he tried turning the coupling of the hose, the nozzle insisted on turning with it, and his imprisoned finger was averse to revolving.
Lapsing again into rueful speculation, he tried desperately to devise some means of regaining his liberty. Why not go ring the elevator bell? No ”

“ Some of the giant nozzles spout streams from 2 to 8 inches in diameter with a pressure of from 50 to 200 pounds per square inch. The powerful streams tear into the gravel banks, washing them away into sluices in which riffle boxes are placed to catch the precious metal. The back pressure of these nozzles is very heavy and the larger ones have to be provided with strong anchorages. Water in motion resists any change of direction and long levers have to be provided to permit the miners to guide the nozzles.
The hydraulic jet is also used for general excavating wherever water power is available. ”