US1194824A

US1194824A - Ethaw i

Info

Publication number: US1194824A
Authority: US
Publication date: 1916-08-15
Anticipated expiration: 1933-08-15

Description

E. I, DODDS.

STAY BOLT FOR BOILERS.

APPLICATIQN man NOV. 30, 1914.

1 (,1 9%,24. Patented Aug. 15, 1916.

l V/T VESSES //VVENI OA Aflormy E TED 1 T ETHAN I. DODDS, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO FLANNERY BOLT COMPANY, OF PITTSBURGH, PENNSYLVANIA.

STAY-BOLT FOR BOILERS.

Application filed November 30, 1914.

To aZZ whom it may concern:

Be it known that I, ETHAN I. Donne, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Stay-Bolts for Boilers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in stay bolts for boilers, the object being to provide a bolt the shank of which will be yielding or flexible so that it may accommodate itself to the unequal movement of the two sheets to which it is secured, without impairing its efficiency to withstand longitudinal stresses to which it may be subjected when applying it to the sheets, or when the boiler is in use.

\Vith this object in view my invention consists in the details of construction as will be more fully explained and pointed out in the claims.

In the accompanying drawings, Figure 1 is a View in elevation of a stay bolt blank embodying my invention; Figs. 2 and 3 are views in transverse section on the lines 22 and 33 respectively of Fig. 1; Fig. 4: is a view partly in elevation and partly in longitudinal section of a modified form of bolt, and Figs. 5 and 6 are views in transverse section 011 lines 55 and 66 respectively of the bolt shown in Fig. 4f.

In the manufacture of the bolt, a bar of stay bolt metal preferably cylindrical is subjected to an upsetting heat and swaged between dies or other suitable tools to produce the reduced shank 1 and the enlarged

heads

2 and 3. During the operation of swaging or before or after the same, the shank 1 of the bolt is slotted on its opposite sides part way through. This slotting as at 4, is continuous throughout the length of the shank, and is deepest from the head 2 to about midway the shank, or to the point 7 5, the web 6 separating the two slots at this end of the shank being comparatively thin. From the point 5 to the other head 3, the slots are much shallower, so that the web 7 separating them is thicker, thus making the half of the shank adjacent the head 3, flexible to a certain extent but more rigid than the half adjacent the head 2, thus localizing Specification of Letters Patent.

Patented Aug. 15, 1916.

Serial no. 874,825.

' contraction and expansion of the inner and outer sheets of the boiler, to that portion of the shank which is adjacent the outer head of the bolt. This outer head of the bolt is provided with a tell tale hole 7 for the escape of steam or water in the event the bolt should break. The greatest stresses fall on a stay bolt adjacent the outer head, hence by making this part of the bolt so that it will yield or give with the boiler sheets instead of resisting their movements, the danger of breakage is reduced'to a minimum, but if it should break, the fracture will expose the tell-tale bore and permit the steam to es cape. Substantially the same result-may be accomplished with the construction shown in Figs. at to G inclusive. In this latter form, each slot extends all the way through for about half the length of the shank and part way through for the remainder of the way. Thus the sloti starting from head .2 passes entirely through the shank to the point 9, leaving the web 10 separating the ends thereof adjacent the bolt head -3,while the slot 1-, which is at right angles to slot 45, starting from head 8, extends through the web 10 and after it leaves the end 9 of the latter, it divides and is separated by a web 10 With this construction the shank of the bolt is flexible throughout its length, but as the side walls of the slots are tied by the

webs

10 and 10, there can be no buckling or binding of the shank, dueto endwise stress either pulling or compressive. This slotting does not remove any of the metal but simply pierces it so that the capacity of the shank for endwise stresses is not weakened, and renders the shank sufficiently flexible laterally so as to permit it to give or yield and thus accommodate itself to the unequal expansion of the inner and outer sheets of the boiler.

Having fully described my invention what I claim as new and desire to secure by Letters-Patent, is

1. As a new article of manufacture, a stay bolt the shank of which is provided with .slots each extending lengthwise the shank, and an integral web separating said slots and reducing the depth of the latteradjacent one head.

2. As a new article of manufacture, a stay bolt having integral heads and a shank Copies of this patent may be obtained for length, the said slots being separated by an integral web.

In testnnony whereof I have signed this specification 1n the presence of two subscribmg witnesses.

ETHAN I. DODDS.

\Vitnesses l VM. CHARLES BINGHAM, EDWIN SPENCER RYOE.

five cents each, by addressing the Commissioner of ?a.tents, Washington, D. C.