US3664310A - Fluid projection apparatus for cleaning heat exchangers - Google Patents

Abstract

A combined soot blower and liquid projector for cleaning boiler surfaces has a main lance tube telescopically overfitted on a feed tube and carrying a nozzle assembly at its outer end for projecting steam and/or air supplied through said tubes, a second pair of telescoped tubes inside and substantially smaller in diameter than the two tubes first mentioned and including a slidable liquid lance having a jet member connected to the nozzle assembly to discharge liquid at right angles to the stream or air. During projection of liquid, steam and/or air is supplied to the outer tubes to cool them and the nozzle assembly.

Description

United States Patent Locke, Sr. et al. [45] May 23, 1972 [54] FLUID PROJECTION APPARATUS FOR 2,958,311 11/1960 Singleton 122/392 CLE G HEAT EXC G FOREIGN PATENTS OR APPLICATIONS [72] Inventors: James W. Locke, Sr.; John C. Goeller Ill,

both of Lancaster, Ohio 669,895 1/1966 Belgmm ..l5/317 [73] Assignee: Diamond Power Specialty Corporation, Primary Examiner-Kenneth Sprague Lancaster, Ohio Attorneyl-Iamess, Dickey & Pierce [21] Appl 139383 A combined soot blower and liquid projector for cleaning boiler surfaces has a main lance tube telescopically overfitted Related Apphcauon Dam on a feed tube and carrying a nozzle assembly at its outer end [63] Continuation of Ser. No. 16,291, Mar. 4, 1970, abanfor projecting steam and/or air supplied through said tubes, a cloned. second pair of telescoped tubes inside and substantially smaller in diameter than the two tubes first mentioned and in- [52] US. Cl ..122/379, 122/390 Cluding a slidable liquid lance having a jet member connected [5 1 Int. Cl ..F22b 37/48 to the nozzle assembly to discharge liquid at right angles to the [58] Field of Search ..l22/379, 390, 391, 392; stream or a r. Dur ng projection of l qu d, stea and/0 air is 16/316, 317, 318 supplied to the outer tubes to cool them and the nozzle assembly.

[56] References Cited 6 Claims, 5 Drawing Figures UNITED STATES PATENTS 1,809,221 6/1931 Snow et a1. ..l22/392 FLUID PROJECTION APPARATUS FOR CLEANING HEAT EXCHANGERS This application is a continuation of application Ser. No. 1 6,291, filed Mar. 4, 1970, now abandoned.

BACKGROUND OF THE INVENTION In the art of cleaning the heat exchanging surfaces of boilers and the like by projecting fluids thereagainst throughsoot blowers and similar apparatus, preferred practice involves the use of air or steam as the blowing medium (although a mixture of these has sometimes been used). It has long been recognized that where difficult cleaning conditions exist, as where heavy slagging occurs, the projection of water or an aqueous solution in lieu of or in conjunction with steam and/or air provides increased cleaning efiiciency. The trade avoids the use of water or aqueous solutions, except where cleaning is not otherwise possible, however, because of certain disadvantages, including the undesirable cooling effect and the necessity for careful control to avoid undue thermal shock.

The general object of the present invention may be characterized as to provide an improved apparatus and method whereby both a liquid cleaning agent and gaseous and/or vapor cleaning agents may be efficiently projected against the heat exchanging surfaces. It is also an object of the invention to provide improved apparatus of the indicated character which is compatible with and readily interchangeable with standardized commercial types of soot blowers and which in its construction incorporates many components identical with those employed in the construction of such soot blowers, the apparatus of the present invention being adapted to be substituted for or added to regular or existing soot blowers, as this may be advisable, for example, where fouling is severe or where a change of fuel or other changed conditions creates heavy slagging and difficult cleaning conditions.

Other objects and advantages will become apparent upon consideration of the present disclosure in its entirety.

BRIEF DESCRIPTION OF THE FIGURES OF DRAWING FIG. I is a side elevational view partly broken away and partly in section showing a dual fluid projector constructed in accordance with the present invention;

FIGS. 2 and 3 are detailed sectional elevational views on a larger scale of fragmentary portions of the apparatus corresponding to the parts in the areas designated by the circles II and III respectively of FIG. 1;

FIG. 4 is a detailed longitudinal sectional view of the nozzle assembly and adjacent parts, also on a larger scale and partly in elevation, taken substantially as indicated by the line and arrows IVIV of FIG. 1 and looking in the direction of the arrows; and

FIG. 5 is a fragmentary sectional view of the rear portion of a nozzle body generally similar to that shown in FIG. 4 but showing a modified double-nozzle liquid discharge construction.

DETAILED DESCRIPTION OF PREFERRED FORMS OF THE INVENTION Referring now to the drawing, reference character designates the main supporting beam of the device, the beam and the principle driving components being shown as corresponding to those employed in a well-known type of long retracting IK soot blower. Such components will require no detailed description. They include a main or outer lance tube portion 12 projectable through a wall box 14, toward the right in FIG. 1, into a boiler (not shown) and retractable therefrom to the withdrawn position shown. The outer lance tube portion I2 corresponds to a conventional lance tube, being rotatable as well as longitudinally movable by means including the carriage I5 and motor 16, and is slidably overfitted upon a stationary feed tube 18 which projects thereinto from the rear to supply blowing medium thereto. As shown in FIG. 2, the feed tube 18 is connected to a fitting 20 carried at the rear end of the assembly having a straight through passage 22 therein through which the principal blowing medium such as steam and/or air may be supplied from a suitable supply system (not shown) which conventionally may comprise a source of steam or air and a main blowing medium control valve (not shown) as is well known in the art.

The fitting 20 also includes a side opening 24 which is connected to a liquid supply pipe 25 which may be a source of water under pressure delivered thereto, the pipe being welded to a side nipple portion 26, but the interior of the water pipe being connected to a conduit 28 which is bent at right angles to communicate only with a stationary liquid feed tube 30 concentrically supported in and of substantially smaller diameter than the feed tube 18, and projecting forwardly therein The complete lance assembly, which is generally designated 11, includes, in addition to the outer tube 12, an inner liquid conducting lance tube portion 33 which travels and rotates with the main lance tube portion 12 and is slidably overfitted on the liquid feed tube 30, and remains interengaged therewith at all times to conduct liquid from the feed tube 30 to a nozzle assembly comprising a nozzle body generally designated 35 attached to outer end of the lance tube assembly. The liquid lance tube 33 is spacedly axially supported in the main blowing medium feed tube 18 by radial spacing fins 32 which interpose no substantial resistance to free flow of blowing medium through the main feed tube 18. The liquid feed tube 30 is in turn supported by the liquid lance tube.

The interior of the outer shell 37 of the nozzle body 35 communicates with the main lance tube 12 and contains a pair of diametrically opposed nozzle elements 36 for discharging the gaseous or vapor cleaning agent against the heat exchanging surfaces as the lance travels and rotates within the blower. The arrangement and operation of the aforementioned nozzle portions may conform to conventional soot blower practice.

At its forward end the traveling liquid supply lance tube portion 33 is connected by means of an elbow 38 to a water nozzle 40 which discharges through an opening 42 in the side wall of the nozzle body, the water nozzle being surrounded and shielded by the tube 44 whichis welded to the nozzle body 35 and to the elbow to support the latter and the water nozzle. The water nozzle discharges perpendicularly to both of the main nozzle elements 36 so that the blast patterns are not disturbed if both types of media are used simultaneously.

Under severe slagging or other difficult cleaning conditions, water or a suitable aqueous solution may be discharged through the liquid nozzle 40 either with or prior to the main blowing medium discharge through the nozzle elements 36. The preferred method includes a preliminary discharge of liquid sufficient to wet the heavily encrusted surfaces for an instant and create a cooling effect to shrink and crack the crust, whereafter the full volume discharge of steam and/or air completes the cleaning operation. Throughout the period in which the lance is projected, however, including the period of the initial liquid discharge, a reduced amount of the steam and/or air is supplied through outer tube 12 of the lance and the outer shell 37 of the nozzle body, at a relatively low pressure compared to the full blowing pressure, to cool these parts and prevent them from being overheated and damaged. This is desirable because of the fact that the presence of the liquid in the inner pair of tubes 30, 33 cannot protect the outer portions of the lance and nozzle body in high temperature regions, on account of the high insulating effect that would exist in the spaces between tubes 12, 18, 33 and in the nozzle body shell 37, if these spaces were empty.

In the modified nozzle construction shown in FIG. 5, two liquid discharge nozzles 40 are provided, both lying in a plane perpendicular to the nozzle means 36' for the main blowing medium although inclined to the axis so as to sweep displaced helices, as shown.

This Detailed Description of Preferred Forms of the Invention, and the accompanying drawings, have been fumished in compliance with the statutory requirement to set forth the best mode contemplated by the inventors of carrying out the invention. The prior portions consisting of the Abstract of the Disclosure and the Background of the Invention are furnished without prejudice to comply with administrative requirements of the Patent Office.

What is claimed is:

1. Means for discharging liquid and a gas or vapor into a high temperature zone of a furnace or the like comprising in combination with a support, a lance tube supported thereby for rotation and longitudinal travel so as to move a forward end thereof into and out of such a zone, a hollow nozzle body carried by the forward end of the lance tube and having a lateral discharge orifice therein, and means for feeding a gas or vapor through the lance tube and out through said orifice, characterized by a pair of telescopably interfitted tubes within and substantially smaller in diameter than the lance tube and comprising a liquid feed tube fixed with respect to the support, a liquid lance tube slidably interfitted with the liquid feed tube and projecting forwardly therefrom within the first-mentioned lance tube and connected thereto at its forward end to move therewith, said liquid feed tube and liquid lance tube being isolated from the interior of the first-mentioned lance tube, the liquid lance tube having a liquid discharge orifice opening laterally outwardly through and to the outside of the nozzle assembly at an angle displaced sufficiently from the first-mentioned discharge orifice so that the blast patterns from said two orifices do not disturb one another when operating simultaneously.

2. Means as defined in claim 1 wherein said two discharge orifices are substantially at right angles to each other.

3. The method of operating a dual discharge projection-type tubular cleaning device for furnaces and the like which device is adapted to be projected into and retracted from a hot zone, and which has radially spaced isolated passages including an outer passage for gas or vapor and an inner passage for liquid, comprising conducting liquid through the inner passage and discharging it therefrom into such a hot zone while simultaneously conducting gas or vapor through the outer passage at a relatively low flow rate and discharging it in a different direction into such zone, and thereafter increasing the pressure of discharge of the gas or vapor.

4. Means as defined in claim 1 wherein said orifices discharge in longitudinal axial planes which are perpendicular to each other.

5. Means as defined in claim 4 including at least two liquid discharge orifices directed in opposite directions in a common plane perpendicular to the discharge plane of the first-mentioned orifice.

6. Means as defined in claim 4 including at least two liquid discharge orifices directed in opposite directions in a common plane perpendicular to the discharge plane of the first-mentioned orifice, but inclined to the longitudinal axis.

Claims (6)

1. Means for discharging liquid and a gas or vapor into a high temperature zone of a furnace or the like comprising in combination with a support, a lance tube supported thereby for rotation and longitudinal travel so as to move a forward end thereof into and out of such a zone, a hollow nozzle body carried by the forward end of the lance tube and having a lateral discharge orifice therein, and means for feeding a gas or vapor through the lance tube and out through said orifice, characterized by a pair of telescopably interfitted tubes within and substantially smaller in diameter than the lance tube and comprising a liquid feed tube fixed with respect to the support, a liquid lance tube slidably interfitted with the liquid feed tube and projecting forwardly therefrom within the firstmentioned lance tube and connected thereto at its forward end to move therewith, said liquid feed tube and liquid lance tube being isolated from the interior of the first-mentioned lance tube, the liquid lance tube having a liquid discharge orifice opening laterally outwardly through and to the outside of the nozzle assembly at an angle displaced sufficiently from the firstmentioned discharge orifice so that the blast patterns from said two orifices do not disturb one another when operating simultaneously.

2. Means as defined in claim 1 wherein said two discharge orifices are substantially at right angles to each other.

3. The method of operating a dual discharge projection-type tubular cleaning device for furnaces and the like which device is adapted to be projected into and retracted from a hot zone, and which has radially spaced isolated passages including an outer passage for gas or vapor and an inner passage for liquid, comprising conducting liquid through the inner passage and discharging it therefrom into such a hot zone while simultaneously conducting gas or vapor through the outer passage at a relatively low flow rate and discharging it in a different direction into such zone, and thereafter increasing the pressure of discharge of the gas or vapor.

4. Means as defined in claim 1 wherein said orifices discharge in longitudinal axial planes which are perpendicular to each other.

5. Means as defined in claim 4 including at least two liquid discharge orifices directed in opposite directions in a common plane perpendicular to the discharge plane of the first-mentioned orifice.

6. MEans as defined in claim 4 including at least two liquid discharge orifices directed in opposite directions in a common plane perpendicular to the discharge plane of the first-mentioned orifice, but inclined to the longitudinal axis.

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