US120235A

US120235A - Improvement in the manufacture of boilers, steam-cylinders, fittings

Info

Publication number: US120235A
Authority: US
Publication date: 1871-10-24
Anticipated expiration: 1888-10-24

Description

, GEoRGE w. BOLLMAN. u Improvement in Manufacture of Boilers, Steam Cylinders, and Flttmgs.

No. 120,235, Parentedom, 24,1871.

PATENT OEEIoE.

GEORGE W. BOLLMAN, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN THE MANUFACTUTIE 0F BUILERS, STEAM-CYLINDEHS, FITTINGS, &c.

Specification forming part of Letters Patent No. 120,235, dated October 24, 1871.

To all whom t may concern:

Beit known that l, GEORGE W. BOLLMAN, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and use'- ful Improvement in Manufacture of Boilers and Fittings; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawing forming part of this specica-tion, in Which- Figure l is a view of a portion of a steam-boiler patented in Letters Patent No. 107,181. Fig. 2 is a view of a steam-cylinder; and Figs. 3, 4, 5, 6, and 7 are views of gas and water-pipe fittings.

In the manufacture of gas and water-fittings, tubular boilers, and steam-cylinders heretofore a soft iron has been used, because the harder varieties are very expensive to bore out and finish, the grain being too coarse and hard. rIhe soft iron, although easy to cut, is not susceptible of a high finish, and Yis otherwise not suitable for the purpose, being somewhat porous in its texture.

By experiment I have discovered that iron and steel combined in a certain proportion give a metal of a superior toughness and of a closer grain than cast-iron, and which is susceptible of a fine finish, and affords a better surface for cutting screw-threads. The amount of steel I combine with a given quantity of iron is from ten to fifteen per cent. of the whole quantity. The iron and steel are melted together in afurnace of the ordinary construction, and the casting done in the usual way. For this purpose I generally use a low grade of lsteel--scrapsteel or carbonized ironalthough any kind may be used. The proportions given may be varied somewhat, depending on the quantity of iron and steel used. If a greater hardness is required the quantity of steel is increased.

Vhat I claim as my invention, and desire to secure by Letters Patent, is-

The manufacture of steam-boilers, cylinders, and fittings from a mixture of cast-iron and steel or carbonized iron, substantially as herenbefore described.

In testimony whereof I, the said GEORGE W. BOL'LMAN, have hereunto set my hand.

. GEORGE W. BOLLMAN.

Witnesses:

JOHN A. FLOYD, JAMES I. KAY. (85)