US235406A

US235406A - Edwin h

Info

Publication number: US235406A
Authority: US
Publication date: 1880-12-14
Anticipated expiration: 1897-12-14

Description

H.111; BENNETT. Tub e 'I a; s ten'i n g's.

Patented Dec. 14, 188 0.

N-PETERS, F lOTO-UTNDGRAPHER, WASHINGTON, u c

UN TED STATES PATENT OFFICEO EDWIN H. BENNETT,.OF BAYONNE, N W JERsEY, ASSIGNOR To eEoReE H. BABOOOK AND sTEPHEN wrncox, OF NEW YORK, N. Y.

TUBE-FASTENING.

SPECIFICATION forming part of Letters Batent No. 235,406, dated'December 14, 1880.

Application filed October 29, 1879.

. To all whom it may concern:

Be it known that I, EDWIN H. BENNETT, of Bayonne, Hudson county, and State of New Jersey, have invented certain new and useful I 5 Improvements relating to Tube -Fastenings; and I do hereby declare that the following is a full and exact description thereof.

The invention is adapted for securing the tubes of steam-boilers and analogous struct- 1o ures requiring a tight fastening, adapted to endure high temperatures and great strains. It is intended more particularly for the style,

of boilers set forth in the several patents to Babcock and Wilcox, having the water inclosed 1 5 in tubes, and small end chambers of cast-iron pered, so that the outer end is the largest. I, employ an expanding-tool, adapted to give the same taper to the tube end and force the metal of the tube into the corresponding conical form, applying only sufficient force to slightly imprint the casting into the outer surface of the expanded tube.

The strain on the connection is always forc- 3 ing the tapered surfaces into a closer connec- A tight joint results with little distor I tion.

lion of the metal of the tube.

My invention allows tubes to serve successfully which possess a less degree of ductility than .is required for the ordinary modes of setting.

The accompanying drawings form a part of I this specification, and represent what Iconsider the best means of carrying out the in- 4 5 vention.

Figure 1 is a central longitudinal section through one of the tube ends and the adjacent parts in the act of being expanded. Fig. 2 is an cndview of the same'with a cross-section through the body of the tube. Fig. 3 is an elevation, partly in section, showing a number of the connections on a smaller scale.

Similar letters of reference indicate like parts in all the figures.

7 A is the body of the tube, and A a conical g5 end formed thereon. B is the main body of i an end casting, and b the tapering hole formed therein to receive the tube.

M M, &c., are the rollers of the expander. They are caged in a ring, N, and are forced 6 apart by a tapering mandrel, P,which is turn ed by a crank or otherwise, and is forced axially, as required, to present a larger diameter within the rollers, and thus to force the rollers M outward and effect the expansion. 6

The hole bin the casting maybe finished with a tool, to give a more exactly mathematical form; but I do not consider such necessary. I esteem it an important advantage of the invention that the holes may be produced with perfection by the ordinary process of casting, and require no tooling. Q

The rollers M may be tapered in the same direction and to the same degree as the mandrel. In other words, the proper degree of taper for the hole being determined, it may be divided between the mandrel and the rollers. This allows the rollers and mandrel to roll together with no sliding and with mathematical precision; but Ido not esteem this feature essential to success. The rollers may be made absolutely cylindrical or tapered in the opposite direction, the mandrel being suitably tapered with each to induce the required degree of taper in the interior, and consequently 0t 8 the exterior of the tube ends A.

I prefer to expand the tubes only to such extent as to slightly imprint the casting B into the outer tapering surface of the tube end A. The bearing-surface is made narrow to 0 facilitate such imprinting.