US1760296A - Skewback block - Google Patents

Description

y 1930. J. BROOKES 1,760,296

SKEWBACK BLOCK Filed Nov. 5, 1927 INVENTOR Patented May 27, 1930 V UNITED STATES PATENT QFFECE JOSEPH BROOKES, OF SPARROWS POINT, MARYLAHD, ASSIGNOR TO BETHLEHEM STEEL COMPANY SKEWBACK BLOCK Application filed November 5, 1927. Serial No. 231,367.

My invention relates to the construction of transversely arched roofs as used in open hearth, annealing and similar furnaces, and

more particularly to the construction of the skewback supports and the refractory skewback bricks used in carrying and transmitting the thrust of such arched roofs to the side walls and metal framework of such furnaces.

It has been customary practice heretofore in constructing the roofs of such furnaces to run channels lengthwise of the furnace along he upper portions of the walls of the same, placing vertical struts outside of these channels, and then tying together the struts by crosswise extending tie-rods. The sides of the arch are abutted against these channels, or against suitably formed refractory blocks which are seated in the channels, so that the thrust throughout the entire length of the roof is taken up by the channels, which in turn are sustained against spreading by means of the crosswise extending tie-rods.

It has been attempted heretofore to protect the lower inturned flanges of the channels as well as possible by surrounding them with fire brick or tile so that they will not be burned by the intense heat within the furnace. However, it has been found after the furnaces have been in use for any considerable time that in almost every instance the lower edges of the channel flanges burn away, particularly above the door-ways of the furnace side walls, because when the fire brick of the walls and roof is burned away the lower flanges are exposed to the intense heat. The result is that a portion of the skewbacks will slip or fall and become displaced in relation to the supporting channels, or skewback supports as they are also called, and will permit the arched roof to fall in part and cause great liability of collapse of pertions and sometimes of the entire roof. Such happenings are the cause of long delays in the operation of the furnace, incurring danger while rebuilding or making repairs and a source of great expense in maintaining the furnace in operative condition.

The principal object of my invention is to overcome the defects mentioned above and to'provide a refractory skewback and skewback support of improved construction and having novel means whereby the skewbacks are maintained in coacting relation against the skewback supports and whereby the life of the skewbacks and skewback supports is materially increased, reducing the liability of damage to the roof by reason of disarrangement of the skewbacks relative to the skewback supports and thereby extend the life of the roof. a

The novel features will be more fully understood from the following description and claims taken with the drawings.

Fig. 1 represents a vertical section 'of a furnacehaving an arched roof embodying my invention;

Fig. 2 is an enlarged sectional view showing details of construction and arrangement of skewback and skewback support in accordanoe with my invention;

. Figs. 3 and i are elevation and end views respectively of the refractory skewbacks forming part of this invention.

Referring to the drawings it will be noted that the furnace is comprised essentially of a front wall-1, a rear wall 2, two end walls 3, but one shown, ahearth 4, and an arched roof 5, the walls and roof being made of any suitable refractory material. The vertical component of the weight of the roof is transmitted to the walls by the skewbacks 6, and the horizontal thrust of the arch is transmitted by the skewback bricks 6 to the skewback supports 7, and thence to the vertical struts or buckstays 8, which are suitably attached to the foundation structure 9 at their lower ends, and cross-connected at their upper ends by the tie-rods 10. It will be observed that in my improved skewback construction as illustrated in Figs. 1 and 2 that the ends of the arched roof engage with. and are supported on the inclined side faces 11 of my improved skewbacks 6, the skewbacks being provided at each side of the furnace and having two vertical faces 12 and 13 abutting against the adjacent faces of the skewback supports 7. At a point intermediate the top and bottom faces of the skewback is an outwardly projecting portion 14 adapted projecting poris preferably made of cast metal of considerable thickness. The cross section being practically that of two integral rectangular portions, the lower portion being of greater thickness than that of the upper portion, thus forming a shelf at a point intermediatethe top and bottom faces of the section which provides a supporting shelf for the skewback brick. At the ends of the skewback support are provided holes for bolts or rivets for attaching to the buckstays 8.

When constructing the arched roof, the skewbacks 6 are placed in position abutting the skewback supports 7 with the outwardly projecting portion of the skewbacks resting on the shelf portion of the skewback supports. The roof bricks are then put in place across the width of the furnace over wooden forms which carry the initial weight of the roof until the roof has set and the supporting strains are taken up by the skewback supports, buckstays, and side walls. It is obvious that the skewbacks, skewback supports, and buckstays are capable of supporting the roof independently of the side walls 1 and 2, although the side walls are built up in close contact with the bottom faces of the skewbacks and skewback supports in the customary manner. I

As heretofore explained, after extended use the skewbacks burn away leaving the lower portion of the skewback supports exposed to the direct heat of the furnace, but due to the thickened lower portion of the skewback sup ports and the shelf formed by the same at a pointconsiderably above the burned portion, support is still maintained which prevents downward slipping of the skewbacks relative to the skewback supports.

It will be seen by those skilled in the art, by constructing the skewbacks and skewback su ports in accordance with my invention, the 11f of the furnace roof, of which my skewbacks form a part, is materially'lengthened and the cost of maintenance and operation of the furnaces greatly reduced.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereon as are imposed by the prior art, or as are specifically set forth in the appended claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A skewback support of substantially rectangular cross section having a face there of of step formation to constitute ashoulder,

said shoulder being normal to the body portion and intermediate the top and bottom edges of said body portion, said face-being continuous from said shoulder to the lower extremity of the support.

2. In a furnace, the combination of a vertical wall, an arched roof, a skewback between the end of said roof and said wall having an upper projecting element, and a skewback support of substantially rectangular cross section having a face thereof of step formation constituting a shoulder for receiving the projecting element of the skewback, said shoulder'being normal to the face of the body portion and intermediate the top and bottom edges of said body portion, and said face being continuous from said shoulder to the lower extremity of the support.

In testimony whereof I hereunto affiX my signature.

JOSEPH BROOKES.

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