US650362A - Twyer for steam-boiler furnaces. - Google Patents

Description

No. 650,362. Patented May 22, I900. S. J. SMITH.

TWYER FOR STEAM BOILER FURNACES.

Application filed Mar. 5, 1900.)

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by vbcwmewmagm No. 650,362. Patented May 22, I900. 8.1]. SMITH.

TWYER FOR STEAM BOILER FURNACES.

(Application filed Mar. 5, 1900.)

(No Model.)

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THE cams PETERS co. PHOTO-LUNG. WASHINGTON a. c.

UNITED STATES 7 PATENT OFFice.

SAM J. SMITH, or LOWELL, MASSACHUSETTS.

TWYER FOR STEAM BOILE R FURNACES.

SPECIFICATION forming part of Letters Fatei'lt No. 650,362, dated May 22, 1900.

Application filed March 5, 1900. Serial No. 71292. (No model.)

To an whom it may concern..-

Be it known that I, SAM J. SMITH, a citizen of the United States, residing at Lowell, in the county of Middlesex, State of Massachusetts, have invented a certain new and usef ul Improvement in Twyers for Steam-Boiler Furnaces, of which the following is a specification, reference being had therein to the accompanying drawings.

My invention relates to twyers, and espe cially to those which are used in boiler-furnaces in connection with an underfeed Stoker, or one which is adapted to introduce fresh fuel into the mass of burning fuel through an opening directly beneath such mass and at the same time to introduce fresh air into the same. My twyer is, however, useful in other connections, as will readily be understood.

The mouth of the twyer for un'derfeed stokers is composed of a series of hollow blocks having air-openings disposed partly or wholly around the inner and outer faces thereof adjacent to the rim of the mouth. Such rim projects upward into the mass of burning fuel, and therefore is subjected to a very intense heat. The twyer-blocks are attached at their lower ends to the double shell of the body of the twyer and form a continuation of the air-space in the shell through which a constant stream of fresh air passes to the fire, issuing through the air-openings mentioned above. The twyer-blocks are of considerable size and weight, are difficult to cast, and are expensive to replace when made in a single piece. The crown portion of the block cracks apart or burns out and renders frequent replacementnecessary. When a block is cracked or partly burned out, fuel and slag enter the air-passages and choke them. Attempts have been made to furnish a removable crown for each block which when cracked or burned out might be replaced by a new one without the necessity of replacing the whole block. Serious difficulty has, however, arisen in respect to the attachment of such a crown to the remainder or base of the block, so as to permitits ready removal from above the twyer, while thoroughly protecting the bolts or other attaching members from being melted by the intense heat and being thus rendered incapable of detachment. In fact, I am not aware of any construction except my own in which the crown can be re moved by access from above the twyer.

My invention is described in the following paragraphs, illustrated in the accompanying drawings, and defined in the claims at the close of this specification.

In the drawings, Figure 1 is a front elevation of a twyer-block provided with my improvement. Fig. 2 is a plan of the base. Fig. 3 is a section of the base and crown on the line 3 3 of Figs. 1 and 2. elevation of the same parts. Fig. 5 is a front elevation of a modified form of base and crown. Fig. 6 is a side elevation of the same, the interior arrangement being shown in dotted lines.

Only the twyer-block has been shown in the drawings, since its mode of connection to the double shell of the body of the twyer is well understood.

Referring first to Figs. 1 to 4, 1 is the base and 2 the crown of the twyer-block. 3 3 are air-openings on the inner or front face thereof, and 4t 4 are air-openings in the outer or rear face. 5 is an interior partition which prevents the air from issuing through the openings 3 3 until it has come in contact with the under surface of the crown 2, and thereby the temperature of the crown is kept as low as possible. 6 is the recess in the outer face of the side of the base in which rests the T- bolt attaching the base to the main body of the twyer.

In accordance with the first part of my invention I pass a bolt directly through the crown and into the air-space in the hollow interior of the block, where it engages with holding means, into which it may be tightly screwed by rotating its exposed head from above the twyer. The said head is preferably countersunk in the upper face of the crown, and the recess above it is filled with ashes, sand, asbestos, or other non-conducting and Fig. 4is a side ineombustible material, which may readilybe removed to obtain access to the bolt. By countersinking the head of the bolt I bring it into contact with the metal of the crown, near the under surface thereof, which surface is constantly cooled by the current of air within the twyer-block. The remainder of the bolt and its holding means are located directly in the said current, and thereby are perfectly protected from all liability of melting together. It may not be found necessary in all cases and with all .degrees of heat to countersink the head of the bolt in the crown;

but I prefer this construction. This portion of my invention is embodied, in Figs. 1 to 4 of the drawings, in a bolt 8, countersunk in a recess 7 in the crown and extending down into the air-space 30 in the block, there passing through a slot 9 between cars 10 10, projectin g fromthe interior face of the base 1. There are preferably two bolts, 850., one near each side, as shown. Below the slot 9 a nut 11 is turned upon the bolt 8. In this construction the crown is applied to the'base with the bolt inserted in it and the nut turned part way upon the bolt. The nut passes down between the partition 5 and the ears 10 10 till it comes below the latter, and then the crown is pushed outward or backward until the stem of the bolt enters the slot 9 and one face of the nut makes contact with the interior surface of the base. Then the bolt is rotated from above, drawing the nut, which is prevented from rotation, snugly against the cars 10 10, and thereby clamping the crown and base together. This operation, of course, is performed while the base is attached to the main body of the twyer. A reverse operation detaches the crown. The corresponding construction is shown in Figs. 5 and 6 as consisting of a bolt 18, countersunk as before, and in this instance 7 screwing directly into a threaded hole bored in the car 19. There are or may be two of these bolts and cars.

In accordance with the second part of my invention I give such a shape to the contiguous surfaces of the crown and base that all lateral strain is removed from the bolt by which they are attached together, while at the same time the contraction and expansion to which the crown is subjected can occur freely without stress between the interlocking surfaces aforesaid. Thus while Figs. 1 to 4 show simple shoulders 12 13, which may in ordinary cases prevent the inward and outward displacement of the crown, I prefer the improved construction illustrated in Figs. 5 and 6 as suited to the most severe and prolonged strains, while fulfilling the other requirements enumerated. The strain on the crown is mostly outward, for as the fuel being fed is ejected from the twyer into the mass of burning fuel on the grate it grinds heavily over the inner edge of the mouth of the twyer and tends to displace outward the crowns that or ribs 14 14 sliding in corresponding grooves in the base. The shoulder 15 takes the outward strain completely. As to the lesser in ward strain, the engaging ribs and grooves are so far below the level of the upper outer edge or the crowh where that strain is applied that the tendency is to tilt the crown instead of sliding it directly inward. Any tilting motion, however, is prevented by the bearing of the ribs in the grooves. At the same time the expansion and contraction of the crown are allowed to take place freely, both laterally and vertically. Thereby the life of the crown is very much extended.

That I claim is 1. In an air-feeding twyer-block, the (30111 bination of a hollow base attached to the main body of the twyer, a removable crown engaging with the base, a bolt passing through a hole in the crown and into the air-space in the base, and holding means located in the interior of the base engaging with the bolt,- whereby the bolt may be loosened and tightened and the crown removed and. replaced by access from above the twyer, substantially as described.

2. In an air-feeding twyer-block, the combination of a hollow base attached to the main body of the twyer, a removable crown engaging with'the base, a bolt passing through a hole in the crown and into the air-space in the base, and an ear projecting from the interior face of the base and engaging with the bolt, whereby the bolt maybe loosened and tightened and the crown removed and replaced by access from above the twyer, substantially as described.

3. In an air-feeding twyer-block, the combination of a hollow base attached to the main body of the twyer, a removable crown en'- gaging with the base, the crown and base having corresponding deep shoulders which resist outward strain and corresponding ribs and grooves which resist a tilting inward strain, whereby the crown is held from displacement while free to expand and contract independently of the base, substantially as described.

4. In an air-feeding twyer-block, the combination of a hollow base attached to the main body of the twyer, a removable crown engaging with the base, a bolt passing through a countersunk hole in the crown and into the air-space inthe base, and holding means located in the interior of the base engaging with the bolt, whereby the bolt may be 100sened and tightened and the crown removed any injured crown can be removed without 10 and replaced by access from above the twyer, loosening the rest, substantially as described. substantially as described. In testimony whereof I affix my signature 5. In an air-feeding tWyer-block, the comin presence of two witnesses.

5 bination of a hollow base attached to the main 7 body of the twyer, a removable crown en- SAM SMITH gaging with the base, and means of attach- Witnesses: ing together the crown and base of each block WM. A. MAGLEOD, A independently of every other block whereby ALICE H. MORRISON.

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