US3000109A

US3000109A - Cooling tunnel for hot sheet or strip

Info

Publication number: US3000109A
Application number: US706489A
Authority: US
Inventors: Francis U Hill; Morton L Simon
Original assignee: JAMES B SHAVER
Current assignee: JAMES B SHAVER
Priority date: 1957-12-31
Filing date: 1957-12-31
Publication date: 1961-09-19
Anticipated expiration: 1978-09-19

Description

Sept 19, 1961 F. U. HILL ET A1. 3,000,109

COOLING TUNNEL FOR HOT SHEET OR STRIP 4 Sheets-Sheet l Filed D90. 5l, 1957 INVENTORS Fkn/vc/s U. HILL BY MOPrQNLS/MGN L7M QQLWQM@y Sept 19 1961 F. u. HILL ETAL 3,000,109

COOLING TUNNEL FOR HOT SHEET OR STRIP Filed Dec. 5l. 1957 4 Shaecrs-Sheei'l 2 Arrows/Ey Sept. 19, 1961 F. U. HILL ErAL 3,000,109

COOLING TUNNEL FOR HOT SHEET OR STRIP Filed Dec. 51. 1957 4 sheets-sheet -5 MMMMIMMHMM Mmm ' INVENTORS 5M vc/5' d //LL BY Makro/v S/MoN ,4 rroRA/E y Sept. 19, F. U HILL ETAL COOLING TUNNEL FOR HOT SHEET OR STRIP Filed Deo. 3l, 1957 4 Sheecs-Sheecl 4 By Mom-on L. /Mo/v d@ Mm( A Tron/va y United States Patent Ohio Filed Dee. 31, 1957, Ser. No. 706,489 1 Claim. (Cl. 34-156) Our invention relates to apparatus for cooling hot strip or sheet and more particularly is an improvement in cooling tunnels for rapidly cooling hot strip or sheet metal, glass or plastic while it is passing through the apparatus.

One of the objects of 'this invention is an apparatus of the above named character by the use of which production of sheet or strip steel may be increased materially and may be accomplished more economically than with apparatus and methods heretofore known.

Another object of the invention is to cool annealed sheet or strip at higher speeds or rates of shorter runs than heretofore.

Another object of the invention is to conserve space by providing an apparatus which will satisfactorily cool hot sheet or strip by passing the same through a cooling tunnel in one direction in a stream of a cooling medium passing through the tunnel and around the sheet or strip in a direction opposite to that of the movement of the sheet or strip.

Another object of the invention is to eliminate the necessity for cooling sheet or strip at room temperatures which methods necessarily require a longer run for the sheet or strip and many times the oor space as contrasted to that which is utilized in practicing our invention.

A further object resides in the metallurgical benefits obtainable through the ability to control the cooling of the sheet or strip.

A still further and important object of the invention is a cooling apparatus of the class described having a dow acceierating nozzle at the coolant input end of the tunnel and a jet diffuser at its discharge end to recover the energy of the coolant stream emerging from the tunnel.

Another object of the invention is to permit the installation of such an apparatus for effective and eicient operation within a limited building floor area and at a high rate of speed as distinguished from the slower and less efficient methods now in use of which we are aware.

Other objects and advantages of this invention will become more apparent as the following description of an embodiment thereof progresses, reference being made to the accompanying drawing in which like reference characters are employed to designate like parts throughout the same.

in the drawings:

FIGURE 1 is a front elevation of an apparatus embodying our invention showing the manner in which the hot sheet or strip is fed through the tunnel in a direction opposite to that of a ow through the tunnel of a coolant, such as air;

FIGURE 2 is a top plan view of the apparatus shown in FIGURE 1;

FIGURE 3 is a side elevation of one end of the apparatus as indicated by line 3-3 of FIGURE l and looking in the direction toward the exhaust manifold;

FIGURE 4 is a. top plan view of an apparatus illustrating a modied form of the invention in which the coolant enters the tunnel from its opposite ends and is discharged through diifusers into a common exhaust intermediate the tunnel ends;

FIGURE 5 is a section on line 5-5 of FIGURE 6; and

FIGURE 6 is a side elevation of the apparatus shown in FIGURES 4 and 5.

ice

Heretofore, so far as we are aware, the cooling of hot strip or sheet annealed steel has been accomplished by different methods, that is, by water spraying, roll cooling or water baths, or by passing the strip lengthwise over rollers for relatively long runs with the sheet or strip'l exposed to the room air which will slowly cool the same, but one of the great disadvantages is that by such method of room air cooling, ythe sheet or strip must be moved linearly over considerably long distances to adequately cool the same for coiling. Under such practice, a lot of space was required and, in many cases, new buildings or additions to buildings were necessary to provide the adequate run space for the sheet or strip during the coolingV phase. As has been pointed out above, it is an important object of this invention to provide means whereby the hot sheet or strip may be more quickly and adequately cooled by air in a relatively short linear run, thus making it unnecessary to provide buildings of a length sutiicient to coil the strip under the old methods.

In carrying out the present invention, we have illustrated in the drawings two embodiments thereof as applied in use for rapidly cooling metal, glass or plastic in sheet or strip form, and will now proceed to describe .the same and its operation, referring first to FIGURES l, 2 and 3, which illustrate one form of the invention.

We have found that by causing the hot strip of sheet to travel in one direction through an air tunnel, and in spaced relation thereto, and at the same time to cause a coolant, such `as air, to be forced at high velocity through the tunnel and around the hot sheet or strip and moving in a direction opposed to that of the direction of the sheet or strip, that the principal objects of this invention are easily attained, that is, the relatively short distance the hot sheet or strip will have to travel, the consequent saving of linear travel of the hot sheet or strip in the tunnel and the consequent lack of requirement of a relatively long tunnel, as contrasted to previous methods, the resultant material increase in productive capacity, the utilization of a high velocity cooling air stream surrounding the sheet in the tunnel and injected into the tunnel through a ow accelerating nozzle, together with a jet diffusing means located at the discharge end of the tunnel whereby the energy of the cooling air stream may be recovered as the heated air is communicated to the discharge or outlet manifold of the apparatus.

More specilically, the embodiment illustrated in FIG- URES 1-3, inclusive, includes a means for supplying a cooling air stream at high velocity which is indicated generally by the supply manifold 1, a discharge manifold 2 and a connecting tunnel 3 whereby a cooling air stream from the supply manifold may be directed through the tunnel and thence outwardly to the exhaust manifold, as will be described in greater particular hereinafter.

The hot strip or sheet to be cooled is indicated generally at 4 in FIG. 1 and, as indicated by the arrows, is caused to move from left to right through the two manifolds and the cooling tunnel, the same being supported between suitable rollers S mounted in the supply manifold and also between the rollers 5 mounted in the discharge manifold.

The supply unit or manifold 1 comprises a housing in which is mounted an electric motor 6 for driving the impeller 7, there'being a guard 8 disposed over the motor and having an open mesh construction whereby air may be admit-ted through the guard to be driven by the impeller 7 downwardly through the housing 9 and into the

twin manifold sections

10 and 11, as indicated by the arrows in the input unit to the right of FIG. l. Within the manifold 1 is provided an accelerating nozzle indicated generally at 12, which communicates the air ow under the pressure of the impeller into the tunnel 3 at ,its right hand end at high velocity in FIG. l, through column to pass upwardly through the ducts of

manifold sections

16 and 17 and into the discharge warmed air outlet 18 where the column will be forced outwardly through the discharge duct 19 by means of the fan 20 operated by the electric motor 21.

It will be noted that the tunnel is of generally rectangular shape in cross section, being wide enough to accommodate the sheet or strip for free linear movement therealong, as indicated in FIG. 3, and being of relatively short height in cross section as seen in FIG. 3, but aiording an air ow space or air envelope through which the sheet or strip may have unrestricted passage. Access

doors

22 and 23 may be provided along the sides of the tunnel at desired points. The tunnel 3 includes upper and

lower walls

24 and 25, respectively, which are in close proximity to the top sheet or strip 4 passing therebetween but which are spaced from the sheet or strip or from each other suiciently to provide adequate flow of high velocity cooling air substantially all around the sheet as it passes through the tunnel.

Partitions or

walls

30 and 31 are provided vertically in the

manifolds

1 and 2, respectively, and each has a mouth or opening 32 extending toward the rollers 5 and to provide for the passage of the sheet or strip 4 therethrough. Flanged portions 33 are provided to lie close to the periphery of the rollers 5 and '5' so as to supply a partial seal therebetween thus effectively directing the cool air flow from the supply manifold through the accelerating nozzle 12, the tunnel 3 surrounding the moving Strip 4, the jet d iiuser 14 and finally out of and through the discharge manifold.

It is desirable that there be a slight sag in the tunnel, as at 40, between the accelerating nozzle and the jet diffuser to accommodate the natural sag of the sheet or strip in the tunnel since in this area there are no supporting rollers provided.

Referring now more particularly to FIGS. 4, 5 and 6, we will describe the embodiment illustrated therein. In this 'form of the invention, we also employ means for accelerating the movement of the coolant to relatively high velocity as the same enters and passes through the tunnel and around the sheet or strip toward the discharge end of the tunnel. Furthermore, we employ a jet diffuser at the discharge end of the tunnel.

In the present embodiment, however, We employ a cooling tunnel consisting of a pair of aligned tunnel units each of which extends outwardly from opposite sides of a coolant discharge manifold and forming with the manifold a continuous passage or tunnel for the sheet or strip to be cooled.

We, therefore, provide the two tunnel units 50 and 51 supported in a substantially horizontal position but presenting a slight sag from the outer ends of the respective units inwardly toward the discharge manifold to accommodate the natural sag of the sheet or strip passing therethrough. An accelerating nozzle is secured at each end of the assembled tunnel as at l52 and 53, and each nozzle has connection with a source of coolant such as air under pressure from a blower (not shown).

'I'he inner ends of the tunnel units 50 and 51 are each provided with a jet diffuser as at 54 and 55, both having connection at their enlarged ends with the coolant discharge manifold or outlet at 56.

The manifold 56 is connected with a chamber or housing 57 within which may be mounted an impeller (not shown) for forcing the coolant discharged from the tunnel upwardly and outwardly through the flue 58. This hue may have communication with a duct or the like to convey the used coolant out of the build'mg housing the apparatus.

lIn this form of the invention, it will be noted that the coolant is introduced into the tunnel at its opposite ends through the accelerating nozzles 52 and 53, and consequently travels through the tunnel from its end portions, enveloping the sheet or strip passing through the tunnel, to be discharged at the intermediate section through the respective jet diffusers 54 and 55 and into the discharge manifold 56. lThus, while the hot sheet or strip to be cooled enters the tunnel, say from the left side of FIG. 6, as indicated by the direction arrow to the left of the ligure, and passes `through the tunnel, it will be enveloped in the high velocity coolant stream moving in the same direction as the sheet or strip for that portion of the latters travel from that end of the tunnel through the jet diffuser 54. As the sheet or strip continues through the jet diffuser '55, the tunnel section 51 and out through the accelerating nozzle 53, it will be moving in an envelope of high velocity coolant traveling in a direction opposed Vto that of the sheet or strip.

iBy such an apparatus, we have provided means which will effectively and quickly cool hot sheet or strip along a linear path of greatly reduced length as contrasted to present day cooling apparatus of which we are aware. By the use of accelerating nozzles at the coolant input, we obtain a high velocity coolant stream through the tunnel while the jet diiusers employed recover much o-f the energy of the coolant stream emerging from the tunnel.

Various changes may be made in the details of construction and arrangement of parts of the invention without departing from the spirit thereof or the scope of the appended claim.

We claim:

In an apparatus for rapidly cooling longitudinally moving hot metal strip or sheet, an elongate straight through cooling tunnel open at its opposite ends to the outside atmosphere and through which the strip or sheet to be cooled is passed in one direction, said tunnel including a pair of axially aligned sections forming a continuous tunnel through which a cooling lluid is moved at high velocity, means for injecting a sheet or strip enveloping cooling fluid into both ends of the axially aligned tunnel sections, iiuid velocity accelerating means carried by the opposite ends of said tunnel for injecting the cooling uid at high velocity into the respective tunnel sections, opposed jet diffusing means intermediate the tunnel ends for discharging the spent cooling fluid from each of the tunnel sections, said opposed jet diifusing means increasing in cross sectional area toward an exhaust manifold and substantially equally on both sides of the longitudinal axis through the tunnel, an exhaust manifold communicating with the respective diffusing means, and a spent cooling fluid discharge flue communicating with said manifold.

References Cited in the le of this patent UNITED STATES PATENTS 92,210 Richardson July 6, 1869 463,266 Allis Nov. 17, 1891 1,847,915 Bailey Mar, 1, 193 2,012,115 Woodruff Aug. 20, 1935 2,346,764 Kratz Apr. .18, 1944 2,542,064 -Tilden Feb. 20, 1951 2,645,031 Edwards July 14, 1953 2,775,046 Kabelitz Dec. 25, 1956 2,783,546 Armstrong Mar. 5, 1957