US3329414A

US3329414A - Insulated water-cooled furnace supporting structure

Info

Publication number: US3329414A
Application number: US443942A
Authority: US
Inventors: Thomas P Greaney
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1965-03-30
Filing date: 1965-03-30
Publication date: 1967-07-04
Anticipated expiration: 1984-07-04

Description

July 4, 1967 T. P. GREANEY INSULATED WATER-COOLED FURNACE SUPPORTING STRUCTURE Filed March 30, 1965 Flt 1- A. c, T n. r t n.

min H 1 i n T t I u. i, 1 I

INVENTOR. 5 THOMAS P. GREA/VEY A) forney United States Patent Office 3,329,414 Patented July 4, 1967 3,329,414 INSULATED WATER-COOLED FURNACE SUPPORTING STRUCTURE Thomas P. Greaney, Hammond, Ind., assignor to United States Steel Corporation, a corporation of Delaware Filed Mar. 30, 1965, Ser. No. 443,942 13 Claims. (Cl. 2636) This invention relates to an insulated water-cooled furnace supporting structure and more particularly to such structures for supporting steel slabs or billets which are being heated prior to rolling. In a conventional continuous reheating furnace, the slab to be heated is pushed through the furnace on water-cooled skids which extend longitudinally through the furnace and are supported on transversely positioned pipes, which in turn are supported by vertical pipes. The pipes must be insulated to prevent them from absorbing heat. Prior to my invention this was usually done either by applying preformed refractory sleeves or by applying the insulation in plastic form around the pipes. In most cases metallic mesh was used as a reinforcement for the insulation. Typical insulations are shown in Schmidt Patent No. 2,436,452 dated February 24, 1948, and Brough et al. Patent No. 3,149,826 dated September 22, 1964. The metallic mesh acts as a heat conductor to the pipes, thus decreasing its effectiveness. Also when the insulation becomes hot it becomes brittle and cracks as the weight of the slab causes the skids to flex. Thus, maintenance and repair costs were high.

It is therefore an object of my invention to provide an insulated, water-cooled furnace supporting structure which includes means for preventing or limiting cracking of the insulation.

Another object is to provide such a structure in which metallic reinforcement is eliminated.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

FIGURE 1 is a plan view of the structure of my invention;

FIGURE 2 is an enlarged elevation of a portion of FIGURE 1;

FIGURE 3 is a sectional view taken on the line IIIIII of FIGURE 2;

FIGURE 4 is a sectional view taken on the line IVIV of FIGURE 1; and

FIGURE 5 is a view, similar to FIGURE 3, showing another embodiment of my invention.

Referring more particularly to the drawings, reference numeral 2 indicates a horizontal tube for receiving cooling water. A longitudinal skid bar 4 is welded to or otherwise attached to the top of the tube 2. Tube 2 and bar 4 are arranged longitudinally of the furnace, not shown, and are supported by a transverse tube 6 therebeneath. The tube 2 has a plurality of longitudinally extending lugs 8 welded thereto on diametrically opposite sides thereof. The tube 2 is surrounded by a heat barrier 10 which includes a plurality of spaced apart sets of light weight insulating members 12 and a compressible washer 14 between adjacent sets of members 12. There are two members 12 in each set with each member extending around approximately one half the circumference of the tube 2 and being provided with slots 16 for receiving the lugs 8. The members 12 abut each other at their lower ends with a high temperature cement mortar 18 holding them together. The top of the members 12 are flattened out so that they are below the top of the bar 4. A high temperature air setting mortar 20 is provided between the tube 2 and members 12. A similar air setting cement 22 covers the outside of the members 12 and gives longer life thereto. The members 12 are made of a high temperature insulating firebrick such as Insolite. This is a light weight, porous fireclay material well known to those skilled in the art. Insolite weighs approximately 48 lbs. per cu. ft. The washers 14 are made of a refractory insulation material which is compressible under temperature. It is preferred to use an alumina silica material which is melted and then blown with an air or steam jet to produce a fibrous material such as Fiberfrax or Kaowool. While the length of the members 12 may vary it is preferred to have them approximately 9 in. long. I have found that the use of the washers 14 prevents or greatly reduces breakage of the members 12 which would otherwise occur due to the flexing action of the pipe 2.

Barrier 24 used with tube 6 is the same as barrier 10 except that its insulating members 26 are not cut away at the top thereof.

In the embodiment of FIGURE 5 pointed radial lugs 28 are used in place of the lugs 8 and a barrier 30 is provided which is identical to barrier 10 except that the slots 16 are omitted from insulating members 32. Because of the texture of the high temperature insulating firebrick the member 32 may be pressed onto the sharp v lugs 28.

The present invention reduces repair and maintenance costs, adds to the efliciency of the furnace and the quality of the product due to better insulation, and is much cheaper to install. In a typical installation the insulation cost is $5 per lineal ft. as compared to a cost of $12 per lineal ft. for conventional installations.

While several embodiments of my invention have been shown and described it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. An insulated water-cooled furnace supporting structure comprising a tube for receiving water, a plurality of spaced apart sets of insulating members surrounding said tube, each of said insulating members extending around less than the full circumference of said tube, and a compressible washer in the space between adjacent sets of insulating members.

2. An insulated water-cooled furnace supporting structure according to claim 1 including a high temperature air setting mortar between said tube and insulating members and around the outside of said insulating members.

3. An insulated water-cooled furnace supporting structure according to claim 1 in which the insulating members are made of porous fireclay and the washers are made of porous alumina silica.

4. An insulated water-cooled furnace supporting structure according to claim 3 including a high temperature air setting mortar between said tube and insulating members and around the outside of said insulating members.

5. An insulated water-cooled furnace supporting structure comprising a tube for receiving water, a plurality of longitudinally extending lugs attached to and extending outwardly from said tube on diametrically opposite sides thereof, a plurality of spaced apart sets of insulating members surrounding said tube and supported on said lugs, each of the members in each set extending around approximately one half the circumference of said tube, and a compressible washer in the space between adjacent sets of insulating members.

6. An insulated water-cooled furnace supporting structure comprising a tube for receiving water, a plurality of longitudinally extending lugs attached to and extending outwardly from said tube on diametrically opposite sides of said tube, a plurality of spaced apart sets of insulating members surrounding said tube and supported on said lugs, each'of the members in each set extending around approximately one half the circumference of said tube, said insulating members being made of porous fireclay, air setting mortar between said tube and insulating members and around the outside of said insulating members and betweenthe members of each set, and a compressible washer in the space between adjacent sets of insulating members, said washers being made of porous alumina silica.

7. An insulated water-cooled furnace supporting structure comprising a horizontal tube for receiving water, a longitudinal bar attached to the top of said tube, a plurality of spaced apart sets of insulating members surrounding said tube, each of the members in each set extending around approximately one half the circumference of said tube and abutting each other at the bottom thereof and abutting said bar at the top thereof with the top of the members being below the top of the bar, and a compressible washer in the space between adjacent sets of insulating members.

8. An insulated water-cooled furnace supporting structure according to claim 7 including a high temperature air setting mortar between said tube and insulating members and around the outside of said insulating members.

9. An insulated water-cooled furnace supporting structure according to claim 7 in which the insulating members are made of porous fireclay and the washers are made of porous alumina silica.

10. An insulated water-cooled furnace supporting structure according to claim 7 including a plurality of longitudinally extending pointed radial lugs attached to and extending outwardly from said tube on diametrically opposite sides of said tube for supporting said members.

11. An insulated water-cooled furnace supporting structure according to claim 10 including a high temperature air setting mortar between said tube and insulating members and around the outside of said insulating members.

12. An insulated water-cooled furnace supporting structure according to claim 10 in which the insulating members are made of porous fireclay and the washers are made of porous alumina silica.

13. An insulated water-cooled furnace supporting structure according to claim 12 including a high temperature air setting mortar between said tube and insulating members and around the outside of said insulating members.

References Cited UNITED STATES PATENTS- 2,435,362 2/1948 Morton 236-6 2,482,878 9/1949 Schmidt 263-6 2,707,095 4/1955 Parsons et al. 138-149 X 2,884,879 5/1959 Corriston 263-6 3,169,754 2/1965 OReilly 263-6 3,226,101 12/1965 Balaz et al. 263-6 FREDERICK L. MATTESON, ]R., Primary Examiner.

JOHN J. CAMBY, Examiner.

Claims

1. AN INSULATED WATER-COOLED FURNACE SUPPORTING STRUCTURE COMPRISING A TUBE FOR RECEIVING WATER, A PLURALITY OF SPACED APART SETS OF INSULATING MEMBERS SURROUNDING SAID TUBE, EACH OF SAID INSULATING MEMBERS EXTENDING AROUND LESS THAN THE FULL CIRCUMFERENCE OF SAID TUBE, AND