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Publication numberUS509678 A
Publication typeGrant
Publication dateNov 28, 1893
Filing dateApr 3, 1893
Publication numberUS 509678 A, US 509678A, US-A-509678, US509678 A, US509678A
InventorsJohn Howie Pollard
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
John howie pollard
US 509678 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

(No Model.)


Patented Nov. 28, 1893.

gw Zd krnrns PATENT OFFICE.



SPECIFICATION forming part of Letters Patent No. 509,678, dated ovember 28, 1893.

Application led April 3, 1893. Serial No. 468,897. (No model.)

To LZZ whom t may concern:

Be it known that I, JOHN Howie POLLARD, a subJect of the Queen of Great Britain, residing in the city of New York, county and State of New York, have invented a new and useful Stopper for Boiler-Tubes; and Ido hereby declare that the `following is a full, clear, and exact description of my invention, reference being had to the accompanying drawings.

The object of my invention is to stop up leaking or bursted boiler tubes by utilizing the heat of the boiler to set in operation a novel plugging device, without drawing the tires or interrupting the use of the boiler.

To more particularly describe my novel plugging device, I will refer to the accompanying drawings.

Figure 1, shows avertical longitudinal section of a boiler tube 7c, with the plugging device lnserted therein ready for operation,one c nd of the plugging device being shown iu similar section, the other end in side elevation. The boiler tube and stopper are shown broken, the parts omitted being the continuation of the boilertubeand rod a., of the stopper. Fig. 2 shows the saine section of the tube and `plugging device as Fig. 1, and also a similar section of the other end of the plugging device, and the Whole plugging device in operation stopping up the tube. Fig. 3 is a detailed Viewr in cross section of a part of the plugging device shown at g, Figs. l and 2. Fig. LLis another detailed view in similar section of the same part. Fig. 5 is a detailed view in section showing a modification in construction of the like parts f, f, in Figs. 1 and 2. Fig. 6 is a vertical longitudinal section showing a modification in the parts of the plugging de- Vice shown in Fig. 1.

Letter ci, represents a forged metal rod corresponding in length to the boiler tube. The similar collars, b, b, forged upon the rod a, support the strong spiral springs c, c, which bear outwardly on the loose circular Washers d, CZ, facing which are the circular washers e, e', bored with screw thread to fit respectively the screw thread turned on the ends of the forged rod a. The opposing washers, d and e, embrace and support an annular metal band f, and toward their centers are made with bev` eled projections upon which rests the metal coil g. The washers, o3 and e', at the other end of the rod, a, are similarly designed to support a like metal bandf, and like coil g. The washer e', is flanged at i, to prevent the stopper from entering too far within the tube lo. The metal coil g, Figs. 1 and 2, may be formed by ceiling a strip of brass oi' other suitable metal of the desired width and length, binding the coil temporarily with wire w, Fig. 3, and dipping the coil first into inuriatic acid and then into molten fusible metal. After cooling and removing the tying wire, the coil will remain fastened by the quantity of fusible metal taken up in the process of sweating just described. The coil is then ready to be placed between the washers at each end of the stopper.

The annular metal bands f,f, Fig. 1, are grooved on the inner side in V shape as at Z, Figs. l and 2,to facilitate an outward expansion of the metal band undei pressure as shown in Fig. 2; another form of groove, shown at Z, Fig. 5, may also be used to advantage. I prefer to make the expanding band of lead,

`but do not limit myself to the use of metal and any other suitable expansible material may be used for this purpose. The washers, CZ, d, e, e', and the metal bands,f,f, are made of such size as to allow the stopper to freely enter the tube until arrested by the flange t', on the Washer e. The pairs of Washers and inclosed metal bands are arranged apart from each other on the rod, in' order to include as much as possible of the boiler tube. The springs, c, c, are compressed by screwing the washers e, e on the rod a, against the inetal coil g, by the nut ends h, h, and locked by the jam nuts g, g.

The operation of my invention is as follows: The stopper constructed as described is inserted within the boiler tube. The heat of the boiler tube immediately liquefies the fusible metal fastening of the coil g, which, being loosened, expands as shown in Figs. 2 and 4. The expansion of the coils g, frees the Washers d, CZ, and the springs c, c, which compress the bands,f,f, expanding them at Z, Fig. 2, out- Wardly against the side of the boiler tube, thus completely closing the tube at both ends. The bands f,f, are preferably made of a width slightly less than the space between the opposing faces of the Washers when held in check by the fusible coil g, to enable the springs, c, c, to gain momentum on being released. To remove the stopper, it is only necessary to unscreW the Washer e', after loosening the lock nut g, and while holding the squared end of the rod `at a. Instead of the band f, and the fusible coil g, shown in Figs. 1 and 2, tvvo U shaped lead pieces f, f', Fig. 6,witl1 their opposing faces beveled as at Z, may be used, the

loose washer d, being formed With a 'p'rojecting bearing to fit into a corresponding space, provided in the washer e, or eI. This space being filled with fusible metal imafter the spring has been com pressed-,th"e loose Washer is held back against the spring. Within the boiler tube the heat as before liqueties the .fu-L

sibleimetal, which escapes between the rod a, and the loose Washer d, and the lead pieces f,

zo f thereupon compressed and expanded, close up the tube, as before described. To permit the vescape, of the yfusible metal in the form of construction shown in Fig. 6, and to avail of the steam in theboiler tube to aid in expanding the lead band or pieces, the borings quire a large escape of Asteam in the boiler tube to furnish the necessary .pressure to expand the plugging band.

I claiml. In a boiler tube stopper the combination of an expansible band with compressing washers, a fusible check, `and a pressure spring, substantially as described.

2. In a boiler tube stopper the combination of an expansible band with expanding mechanism, and a fusible check, substantially as described.

3. A boiler tube stopper, consisting of a rod carrying at each end a pressure spring, coinpressing Washers, a fusible check, and an expansible band, constructed and arranged substantially as described. i p y l 4. In a boiler tube stopper thecombination of the pressure spring, the compressingjvashers, the fusible metal coil, and the ex-ppansible baud, 'constructed and arranged substantially asdescribed. y p y 5. In a boiler tube stopper the combination of the pressurespring the compressing washers, the fusible metal, and theA expansible band, constructed and arranged substantially as described. D n p y JOHN HOWIE POLLARD. Witnesses:


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4590991 *Jan 9, 1984May 27, 1986Westinghouse Electric Corp.Flexible stabilizer for degraded heat exchanger tubing
Cooperative ClassificationF16L55/134