Pneumatic flue-expander.

Application filed August 28, 1907. Serial No, 390,485.

To all whom it may concern:

Be it known that I, Harry Kelly, a citizen of the United States, and a resident of Houston, in the county of Harris and State 5 of Texas, have invented a new and Improved Pneumatic Flue-Expander, of which the following is a full, clear, and exact description.

This invention relates to means for expanding the ends of flues in the flue sheets 10 of a Steam or other boiler; and the purpose of the invention is to provide novel details of . construction for a flue expander, which will be actuated by air pressure, will effectually affix a flue eiid in the sheet, will avoid all jar 15 and percussion thereupon, and obviate the contingency of a flue creeping endwise while the operation of expanding the.ends thereof is being conducted.

The invention consists in the novel con20 struction and combination of parts, as is hereinafter described and defined in the appended claims.

Reference is to be had to the accompanying drawings forming a part of this specifica25 tion, in which similar characters of reference indicate corresponding parts in all the views.

Figure 1 is a longitudinal sectional view of the improved flue expander, substantially on the fine 1—1 in Fig. 3, Fig. 2 is a trans30 verse, partly sectional view of details, substantially on the fine 2—2 in Fig. 1; Fig. 3 is an enlarged transverse sectional view, substantially on the line 3—3 in Fig. 1; Fig. 4 is a longitudinal sectional view on the fine 4—4 35 in Fig. 5, showing a slightly changed means for holding the swaging dies in position for use;, and Fig. 5 is a transverse sectional view, substantially on the line 5—5 in Fig. 4.

The invention briefly described, com40 prises a cylinder, a piston slidable therein, a rod extended from the piston at one end of the cylinder, an expansible sectional die, means for supporting the die projected from one end of the cylinder, a tapered pin con45 nected at its smaller, end with the outer end of the piston rod, and means for conducting air under pressure into the cylinder at each end of the piston head alternately, and simultaneously exhausting the air pressure at the 50 opposite end thereof, whereby the die is expanded in a flue end by traverse of the tapered pin in one direction, and retracted by a compression spring when the pin is moved in an opposite direction.

In .the drawings, 5 indicates a hollow cylinder of suitable capacity, and 6 a piston slidable in the true bore of the cylinder and forming an air-tight joint therewith.

From the center of the piston 6 a piston rod 7 projects through a packing bbX 6^b Cen- 60 tralinone head 6^a of the cylinder, the rod having sufficient length to permit a proper reciprocation of the piston 6. A Valve chest 8 is formed or secured on the cylinder 5, having a preferably cylindrical valve 8^a therein formed 65 with ports a—a' that may be caused to reg-1 ister alternately with air ducts δ¹—V that respectively extend from the bore of the chest 8 toward opposite ends of the cylinder 5, said ducts intersecting the bore of the cylinder 70 near each head thereof, as shown at δ² in Fig. 1.· An air inlet pipe c, which may be extended to a source of compressed air, opens into the bore of the chest 8. Between the adjacent ends of the air ducts δ—δ' an eX- 75 haust opening d is formed laterally in the chest 8 below the valve 8^a. Said opening, that intersects the bore of the chest, may be conk trolled by a rotatable movement of the valve. At one projecting end of the valve 8^a, a lever 80 8^b is secured by one end, and pro jects at a right angle therefrom, a vibration of the lever correspondingly adjusting the valve.

One means for connecting flue setting dies with, the described construction for service 85 consists of the following details: Upon the end of the cylinder 5 from which¹ the-rod· 7 projects, a bracket frame is secured, said frame consisting of two smaller arms 9, 9 which converge toward their outer ends that 90 are integrally connected together by a collar e said collar having a central opening e⁷. A swaging die 10, for expanding the end of a flue is a detail of the improvement, and as shown in Figs. 1 and 3, consists of a plurality 95 of similar segments g, that have wedge shaped bodies, which when assembled form a substantially cylindrical die having a tapered bore and a peripheral surface the shape of which is indicated in Fig. 1. Preferably the 100 composite die 10 is forpied of eight segments; as represented in Fig; 3; and at one end thereof a bead h is formed, that in use is inserted into the end of a flue that is to be expanded. Near the opposite end of the die a 105 peripheral groove i is formed therein, which receives the laterally bent flanges i¹ upon a series of similar clamps i², that are curved'as shown in Fig. 3. In the'periphery of the foliar e a circumferential groove is formed) 110 and on opposite ends of the clamps i² flanges i³, similar to the flanges i¹ are formed and are

888,23® embedded in said circumferential groove. A shallow groove is formed in the exterior surface of the series of curved clamps i² between the ends of the same, and in said groove a K contractile hoop-like spring i⁴ is embedded, which serves to hold the clamps i² in clasped engagement with the sections of the die 10, that is thus compressed into normal form for introduction within a flue. A pin 11, for - q expansion of the sectional die 10, is employed, having .a gradually tapered body which is circular in cross section and of such dimensions as adapt it for effective service. The smaller end of the pin 11 is threaded as ₁₅ shown at m in Fig. 1, and when arranged for use, is first passed through the die 10 and then through the opening e¹, one end of a sleeve nut m¹ being mounted upon said end of the pin. The outer end of the piston rod 7 2o is threaded as shown at m² and receives the other end of the sleeve nut m¹; thus connecting the rod and pin in axial alinement with each other. ·

In operation it will be observed in Fig. 1 25 that the die 10 is contracted for free insertion into the end of a flue for its expansion, the flue being omitted from the drawings. The piston rod 7 is drawn out of the cylinder 5, thus disposing the piston 6 near the front 30 head of the cylinder, and adjacent to the termination b² of the air duct &. I t will be seen that if the lever 8^b is moved into the position shown in Fig. 1, the valve 8? will have its port a so disposed as to connect the air 35 inlet pipe c with the air duct b that extends forwardly, so that the pressure of compressed air will be imposed upon the forward end of the piston 6. The pressure of the inducted air is so graduated by adjustment of the 40 valve 8^a, that the piston will be moved slowly away from the front head of the cylinder 5 and correspondingly draw the pin 11 through the sectional die 10. Obviously the sliding of the pin will cause the die sections g to 45 spread apart and the diameter of the bead A to be correspondingly increased, which will embed the bead in the inner surface of a flue in which the die may have been inserted. To perfect the operation of “setting” the flue 50 end in a flue sheet, the valve 8^a should be rocked by the lever 8^b so as to push forward the piston that has been pressed rearward, which will shove the pin 11 into the position shown in Fig. 1, and thus permit the spring 55 i⁴ to close the sectional die 10. The entire device may now be turned so as to dispose the sections of the die at points intermediate the indented portions of the flue; then the expansion of the die is repeated, which will 60 force the bead h into the flue and expand the intermediate portions mentioned. If found desirable, the tool may be changed in position several times and effect a perfectly reliable, continuous joint between the flue end 65 and fliie sheet.

In Figs. 4 and 5, the means for holding the die sections g in operative positions on the frame bars 9, 9, as shown, consists in forming a thread e² on the exterior of the collar e and providing a cap nut n mounted- on said 70 thread. On the capped end of the nut n, an inwardly extended annular flange n is formed, which is entered within the peripheral groove n² formed in the end portion n' of the die sections g, and in said groove is seated 75 a circular spring n³. The groove w³ is deep enough to receive the said spring that occupies the bottom of said circumferential groove and clasps the die sections g, holding them in contact with each other at their so edges.

It will be seen that in operation, the tapered pin 11 will by traverse of the rod 7 into the cylinder 5, cause an expansion of the die sections g, and effect the setting of a flue end 35 in a flue sheet as heretofore described with regard to the construction shown in Figs, 1 and 3.

It will be apparent that the employment of the improved flue expander will effect the ex- 90 pansion of flue ends in flue sheets, without percussion such as results from the use of ordinary expanders that are operated by blows from a hammer, so that the flue will not be injured and will be more durable than 95 if the metal should become crystallized due to vibrations resulting from percussion.

It is frequently the case that flues move endwise, when the operation of setting them is conducted with an ordinary flue setting 10( device that expands by use of blows from a hammer. Should this occur, the flue must be removed by cutting it out, and as this renders it too short it must be pieced out before it can be used. 101

It will be seen that the flue expander hereinbefore described, will by avoidance of jar, effect the expansion of flue ends without danger of their moving endwise, and enable perfect work to be done with the tool in a rapid, 11< non-laborious manner..