US2603457A

US2603457A - Multijet heat exchange roll

Info

Publication number: US2603457A
Application number: US60716A
Authority: US
Inventors: Le Roy D Bishop
Original assignee: Armstrong Cork Co
Current assignee: Armstrong World Industries Inc
Priority date: 1948-11-18
Filing date: 1948-11-18
Publication date: 1952-07-15
Anticipated expiration: 1969-07-15

Description

July 15,v 1952 LE ROY D. BISHOP MULTIJET HEAT EXCHANGE Rom.

Suma/WIM LEROY D. B|SHOP Filed Nov. 18, 1948 sgg" Patented July 15, 1952 UNITED `s'mrl-l'fts APATENT OFFICE MULTIJET HEAT EXCHANGE ROLL Le Roy D. Bishop, Kankakee, Ill., assignor to Armstrong Cork Company, Lancaster, Pa., a corporation of Pennsylvania Application November 18, Y1948, Serial No. 60,7716

1 Claim.

This invention relates to a heat exchange roll and is concerned particularly with a calender roll for use in the manufacture of so-called asphalt tile, including a vcontrollable jet injector arrangement for directing a plurality of streams of heat transfer fluid at high velocity against the inner surface of the roll, within the heat transfer cavity therein, to extract heat from the roll to bring the working surface to a desired working temperature, preferably substantially uniform throughout the extent of the working surface of the calender roll. In the manufacture of this product, it is desirable to extract heat from the calendar rolls and this is accomplished by circulating refrigerated brine or other heat transfer fluid through a cavity disposed `within the roll, below the working surface thereof.-

In these calenders it has been found that the temperature Will vary over the length of the working surface of the roll, generally being hotter at the center than adjacent the roll necks where conduction of heat from the roll to the machine frame, bearings, and the atmosphere is greater than at the center. Frequently,l the areas of the working surface adjacent the roll f' necks will be too rcold for proper operation while the center portion will be at a temperature above that desired. In the manufacture of asphalt tile, particularly where a marbleized pattern is produced, it is desirable to maintain a substantially uniform temperature throughout the ex'- tent of the working surface of the rolls in order to obtain a uniform surface smoothness and the desired graining effect.

Attempts have been made to provide heat exchange rolls with injectors of differentV sizes positioned along the length of 4the roll Acavity to thus inject a greater quantity of heat transfer fluid into certain areas of the roll cavity than in others, and to exhaust the heat transfer fiuid in zones adjacent the zones of introduction to thus attain a substantially uniform temperature along the length of the working surface of the roll. While these attempts have been successful in a measure,.it has not been possible to vary the quantity of transfer fluid injected into the roll cavity at the spaced locations along its length without removing the injector mechanism from the roll and replacing the injector heads. It frequently happens in com- -inercial manufacture that temperature conditions will vary during a production run, or bey tween different runs, and it is desirable to compensate for such variations without the necessity of shutting down the machine and dismantling the injector mechanism.

t' velocity and at spaced locations along the length of the cavity and in which independent control of the various injectors is provided to attain a desired temperature relationship in the various locations throughout the length of the rworking surface of the roll.

Another object o f vthe invention is to provide a heat exchange roll with independent injectors positioned to supply heat transfer fiuid to the roll cavity in spaced zones, with external ecntrols provided for regulating the supply of heat transfer fluid to the various injectors, operable without shutting down the operation ofv the roll and without dismantling of the injector mechamsm.

An additional object of the invention is to provide a controllable jet injector arrangement for a heat exchange roll with an exhaust arrangement associated with the injector, the' whole being insertable into a heat exchange roll as a unit. A

A preferred embodiment of the inventioni illustrated in the wattached drawing in which:

Figure 1 is a plan view, partly in section and partly-broken away, illustrating a heat exchange roll in the nature of an asphalt tile calender, embodying the present invention;

Figure 2 is an enlarged sectional view taken on the line II-II of Figure 1; and I Figure 3 is a diagram illustrating the flow of heat transfer fluid. l

Referring to Figure 1, there is shown a heat exchange rollhwhich has beenA generally designated by the numeral 2. It includes a cylindrical working surface 3 and necks 4 and 5. The roll is provided with a heat transfer iiuid cavity C which extends throughout the length of the working surface .of the roll.

A controllable' jet injector, indicated generally by the numeral 6, is arranged for assemblyas a unit with the `heat exchange roll 2. The injector includes a plurality of injector tubes 1. In the embodiment illustrated, there are seveninjector tubes, each indicated by the numeral 1 followedby one of the letters a to g. Each of the injector tubes 'Ia-g is provided with an up- Y, 3 Wardly directed nozzle 8. The number of the injector tubes employed, their size and their spacing will depend upon the size of the roll, the temperature of the heat transfer fluid as injected,

the velocity of flow of the heat transfer fluid,V

the temperature to be attained at the Working surface of the roll, and other variable factors. In a typical asphalt tile calendar roll Where the working surface 3 is lincheslong and the Yheat transfer fluid is brine at a temperature of F.,

supplied at 60 pounds pressure at the manifold,v Yand a temperature of 100 F. is desired at vthe working surface, the tubes 1c, ld',` and 'lefrrlayY have an inside diameter ofl/z inch, andthe tubes 7a, 1b, 1f, and 1g an insidel diameterof% of an inch. The tubes may be positioned in the.

locations shown in Figure 1. The nozzles 8 may be merely copper tube sections or may be conventional nozzles. is to have the nozzles so shaped and so posilthe roll into a sewer.

In order to facilitate the removal of the injector from the roll, a coupling 21 is provided oneach tubefI adjacent the disk I0, and the valves 23- are preferably so positioned that they neednot be. disconnected to permit removal of Y the injector mechanism.

The preferred arrangement tioned that they directjets of heat transfer fluid upwardly against the wall of the chamberv in overlapping zones, as diagrammaticallyv. illustrated in Figure 1. Theftubes 'I are suitably fastened together as by elipse so as to properly support one another in proper spaced relationship. The tubes I arefitted through openings inasupporting disk I0, and the disk I0 is threaded into an end fitting I I. An exhaust conduit I2 is provided for the discharge of spent heat transfer fluid from the cavity C. The conduit I2 is connected to the end fitting II -by a conduit I3 and connecting coupling I4. A discharge pipe I5 is also attachedto theend fitting I I vfor conveying the heat transfer fluid from the roll.

The injector mechanism 6, including the Yinjector tubes 1, Ythe discharge conduit I2, and the associated end fitting and coupling `are joined together into a unitary structure. In order to mount this structure on the roll, a flanged sleeve I6 isrprovided which encircles themember I3 and 'is allxed to the roll 2 at the neck #by` a plurality of machine bolts I'I. Since the roll 2 and the sleeve l'rotate with respect to the in- `jector mechanism 6, suitable sealing arrangements are provided to Vprevent the leakage of heat -transfer fluid. A gasket I8 is used to seal the-joint between the sleeve IIV and the rol-l l2, and a rotating joint arrangement including packing I9, a packing gland 20, and adjusting bolts 2| which are fixed Within the flange of the sleeve Vllt andj'are provided with adjusting nuts.-22 is provided. j The conduit I3 is turned on its-outer surface to a proper finish to permit-sealing by the packing I9. Y Y

In the assembly ofthe injector with'the roll, it is merely necessaryto slide the injector into Yposition and draw up the attaching bolts Il.

As diagrammatically shown -in Figure 3, each vof the injector tubes 'I is provided With Ya valve 2`3- for independently controlling the supply of heat transfer fluid to each of the nozzles 8. This makes it possible to control the volume andveylocity of heat transfer fluid directed into the roll cavity C at the individual spaced locations and thus obtain minute temperature control at the working surface 3. A manifold 24 is preferably provided into which the various tubes'l are-con,- nected.

' lThe discharge conduit I2 .is preferably connected by the pipe I5 to a temperature adjusting means 25,7such as a refrigerating unit adapted to lower'the temperature of the heat transfer vfluid to the desired degree, and thefheat transfer In the operation of the device, heat transfer fluid is supplied to the manifold 24 and the valves 23 are adjusted while the calender roll is in operation, heat transfer fluid 'being projectedthrough the tubes 'I and nozzles 8 against the rotating wall of the roll cavity. Tempera ture measurements may be made at the roll surface. If it is'desired to maintain a substantially uniform temperature throughout the working surface of the roll, adjustment of the valves 23 will bemade to establish such condition. Should the: temperature of the mix fed to the rolls vary during production, or should other variable factorsbeencountered which tendfto'alter the temperature condition at the working surface ofthe roll, adjustments of the valves 23 may be effected While the calender is in operation and the proper control thus established. Since the'manufacture of asphalt tile is effected very rapidly, it is essential to be in a position to very quickly compensate for any changesiin temperature which may occur across the Working surface .of the roll in order to permit sustained quality production.

The system works on the principle of directing controllable jetsr of heat transfer fluid ata high ,velocity to obtain heat transfer from the roll to theheat transfer fluid. This necessitates that the exhaust conduit I2 bev of sufficient capacity to prevent the filling of cavity C With heat transfer fluid. In the typical embodiment illustrated and described using an exhaust conduit 21/2 inches in diameter, the cavity C will not be more than half filled at any time even thoughl each of the injector tubes 'I be wide open and supplying heat transfer fluid at 60 pounds per square inch pressure. V

While I have illustrated and described a preferred embodiment of my inventionyit'will be understood that the same is not limited thereto but may be otherwisev embodied and practiced within the scope of the following claim.

I claim:

Avheat exchange roll comprising a roll body having'a peripheral Working surface the temperature'of which is to be controlled and having a vheat transfer fluid chamberwithin the body thereof and extending substantially throughout 'the length of the working surface; a plurality .of upwardly directed jet injectors disposed within said chamber, opening directly into said chamber above the axis of the roll, and spaced along the length thereof, a plurality of said injectors `disposed at the central portion of the working surface of the roll being larger than a plurality of said injectors disposed at the end portions of the working surface of the roll; a manifold externallyfof the roll connecting said injectors v'to a common source of heat transfer fluidunder pressure; a central conduit having a capacityl greater than the combined capacities of the injectors leading from the chamber adjacent to one end thereof and through which said injectors are disposed, said conduit discharging spent heat transfer uid from the roll cavity .below the axis of the roll. whereby the injectors are unrestricted in theirupward projection of Jets of heat transfer fluid under pressure against the inner surface of the roll cavity; and Valves disposed externally of the roll and interposed between said manifold and said injectors for independently controlling the supply of heat transfer fluid to said individual injectors.

LE ROY D. BISHOP.

REFERENCES CITED The following references are of record inthe le of this patent:

UNITED STATES PATENTS Number Name Date 1,724,676 Y Moxley Aug. 13, 1929 1,813,086 Sahmel July 7, 1931 10 1,994,360 Hurxthal Mar. 12, 1935 2,431,473 Flynn Nov. 25, 1947 2,435,959y Eaby Feb. 17, 1948 2,453,718 Mason et al Nov. 16. 1948