Oct. 15, 1946. - F. ‘o. HESS HEATING 2,409,431 wonx . Filed Aug. 31, ' 1942v ‘a R I ‘ N b- w Ell w ‘ 2 Sheets-Sheet 1 x _- - '= ‘ R a ‘a , Q3 @‘ ‘a I ’ \. oigggllllllllll/ ‘ \\ BY W g/éM A-TTORNEY V ‘ 0a.. 15, 1946.‘ F. O. HESS 2,409,431 HEATING WORK ' Filevd Aug. 31. 1942 2 Sheets-Sheet“ 2 N INVENTOR I FR: ?Pwf/P/c 0. 46/565 59%“ g - ATTORNEY 2,409,431 Patented Oct. 15, 1946 ‘UNITED STATES PATENT OFFICE HEATING WORK Frederic 0. Hess, Germantown, Pa., assignor‘ to Selas Corporation of America, a corporation of Pennsylvania Application August 31, 1942, Serial No. 456,787 23 Claims. (Cl. 263-3) 2 The general object of the present invention is by a heat treatment which melts or fuses the to provide improvements in. heating ‘work, and, tin, but as far as I am aware, no practically satis although not to be limited thereto, is especially factory method had been devised, prior to my useful in the manufacture of tin plate. More invention, for giving the above described hot speci?cally, the primary object of the invention 5 treatment to strip material moving continuously is to‘ provide a novel and effective method of, and past the ?nishing station at a high but varying novel and effective means for hot ?nishing tin speed. plate stock in the form, of a thin strip coated My present invention was devised with the with electrolytically deposited tin while the strip speci?c object in View of providing a practically is travelling at high speed through a finishing effective method and practically effective ap station, paratus for subjecting. tin plate strip stock to the In the manufacture of tin plates it has been above described heat treatment while said stock found that when plate stock is coated with elec~ is moving through a ?nishing station at a speed trolytically deposited tin and is subsequently sub varying from a maximum which may be as high jected to a suitable ?nishing treatment, the tin 15 as 800 feet per minute or higher, and a minimum coating required for a given use of the ?nished which may be as low as 100 or 200 feet per minute, plates made from the stock may be substantially and my invention is characterized by the ad~ thinner than has been found necessary in manu justment toward and away from such strip or facturing tincplates for the same use, from stock other work in automatic response to increasesand plates coated by dipping them in a bath of molten 20 decreasesin the strip speed,‘ of a heat source, such tin as has been customary heretofore. The reduc as refractory ‘heating walls for example, which tion in the thickness of the tin coating made pos are maintained at a temperature much ‘above the sible by, depositing the tin electrolytically on the melting temperature of tin. _ In so adjusting the plate stock, is strikingly large and results in a position of the heat source with repect to the reduction of about 70% in the coating tin, per unit work, the heat source is preferably moved through of area coated, in the manufacture of tin plates distances functionally‘ related to changes in the for ordinary uses. ~ Furthermore, the manufacture of tin plates from electrolytically plated stock can‘ be carried rate of movement of the work.’ By thus varying the distance between the heating walls and the strip, I am able to vary‘the rate at which heat is on more rapidly and, with a lower labor cost than i 30 transmitted from the heating walls to‘ the travel has been‘ practically possible in the manufacture ing strip through the wide range and in the rapid of tin plates from dip coated stock plates. The manner necessary to‘heat the strip material with advantages last mentioned result largely from suitable uniformity notwithstanding wide and the fact that it is practically feasible to coat rapid variations in the speed at which the strip plate stock in strip form by moving it continu J 35 moves through the'treating station. Ordinarily, ously through an elongated electrolytic coating ‘the speed at which the strip material is moved bath and that it has not been found practically through the finishing station may be expected to feasible to satisfactorily coat such strip material vary widely and rapidly as result of operating con by moving it through a molten tin coating bath. ditions in the continuous stripvmill from which Heretofore, tin plate stock has customarily‘ been 40 the tin plate stock, passes to‘ the ?nishing station. coated by the essentially intermittent process of "The apparatus which I have ‘devised comprises moving the stock in" the‘ formfof relatively short a'pair of burner walls of ceramic material at pieces or plates,‘ quickly down into and‘then up opposite sides of the traveling plate stock strip out of a molten tin bath. The hot ?nishing proc— and in each of which a multiplicity of suitable use which I have devised is a continuous, process burners ‘are incorporated. Burners of a type which can be carried out rapidly and at a rela well adapted‘ forsuch ‘use are disclosed in, my tively small expense. 1 i ‘ A thin coating of tin electrolytically deposited prior Patent No. 2,215,079 of September 17,1940. Such burners, commonly known‘as Duradiant on tin plate. stock is initially'in a porous condi burners, are now in extensive use as furnace wall tion and to fit such stockfor'the uses to which 50 burners and‘ for other purposes. The Duradiant tin plates are customarily put, the coating pores type of burner shown by said patent is charac terized by its’ shallow cup-like combustion cham ber formed'i'n a ceramicumaterial body, and by the provisionsmade for supplying a. combustible mix andmade to adhere better to the steel strip body 55 ture of air and gas‘ ‘to the combustion chamber, must be closed. It'has heretofore been found that the coating pores can be closedand‘ that the coat ing can be smoothed and given a glossy ?nish 2,409,431 3 in such manner as to effect the complete com bustion of the mixture within the combustion chamber, and the maintenance of relatively high 4 burner walls D and DA at opposite sides of said path. The wall D is mounted on a truck or car riage E having supporting wheels E’ on rails F’. The rails F’ are mounted on an inclined support combustion chamber temperatures so that a major portion of the heat liberated may be 5 F and extend away from the path of movement of the strip A, and are downwardly inclined, so that the truck or carriage E has a gravitational bias for movement along the rails F’, which will increase the horizontal distance between the contemplate that each burner wall will be wide enough to extend beyond the side edges of the 10, burner wall D and the strip A. The burner wall DA is like the burner wall traveling stock strip, which ordinarily will be 2 radiated away from the combustion chamber through its open end. In the ordinary use of the present invention, I or 21/2 feet wide, and that each wall will extend alongside the strip in the direction of its length for 2 or 3 feet or so, and that in normal operation each burner wall will be spaced away from the strip, a distance varying between a minimum of D, and its supporting carriage EA is similar in form and in the manner in which it is sup ported, to the carriage E. Further the burners, fuel mixture supply connections, and other parts associated with the burner wall D and carriage E, as hereinafter described, are duplicates of parts associated with the burner wall DA and as the speed at which the work strip is moved carriage EA. In consequence the following de through the space between the two burner walls scription of the burner wall D, its burners and is increased and decreased. burner supply connections, will make it unneces The considerable areal extent of the burner sary to separately describe the burner wall DA, wall and the high burner combustion chambers its burners and connections. ‘maintained, ordinarily about 24.00" F., makes it As shown, the burner wall D comprises ceramic possible for the burner walls to transmit heat rapidly enough to melt the tin coatings on the op 25 burner blocks d which may be shaped and as sembled edge to edge as they are in a furnace posite sides of the traveling sheet when traveling one inch or so and a maximum of several inches at a speed as high as 800 feet per minute or higher, although the melting temperature of the tin is about 450° F., and only a small fraction of a second will then be required for the movement of a point on the surface of the tin strip through the space between the burner walls. wall arrangement shown in said prior patent, but the burners may be spaced apart or grouped in any manner which conditions make desirable. Each of the burner blocks d is formed with a cen tral horizontal inlet passage 11' which terminates at the side of the burner wall adjacent the strip A in a shallow cup-shaped combustion chamber In its preferred form my invention comprises d2, coaxial with the passages d’ and open at its means not only effective to automatically move the burner walls toward and away from the 35 end adjacent the strip A. As shown, the burner blocks (1 in each of the different horizontal rows travelling work strip, as the speed of the latter of the burner wall have their inlet passages d’ increases and decreases through a normal regu connected to a corresponding horizontal manifold lation range in which the rate of heat transmis G. The ?ow capacity of the manifold connec sion to the work strip will be proportional to its tion to each burner passage d’ may be independ speed past the burner walls, but also effective ently regulated in a known manner as by means to give the burner walls rapid and substantial of a corresponding adjustable needle valve throt safety movements away from the work strip in tling element d3, accessible for adjustment at the the event of an interruption of, or radical reduc side of the manifold remote from the burner tion in the work strip speed. The means em ployed for giving the burner walls their above 45 wall D. . Each of the superposed manifolds G associated mentioned regulating. and safety movements may with the burner wall D is connected by an indi take various forms. In a preferred form of the vidual regulating valve G’ to a vertically dis invention those movements are gravitationally posed drum G2 mounted on the truck E. A com produced and are regulated by a hydraulic cylin der controlled by a valve which is actuated to 50 bustible mixture of air and gas is supplied at suitable pressure to the drum G2 from a station vary the liquid pressure in the cylinder in auto ary mixture supply main H through an adjacent matic response to changes in the work strip speed ?exible pipe connection H’. of travel. In the form of the invention diagrammatically The various features of novelty which char acterize my invention are pointed out with par 55 shown, the distance between each of the burner walls D and DA and the adjacent side of the ticularity in the claims annexed to and forming work strip A is directly controlled by a servo a part of this specification. For a better under motor J in the form of a hydraulic cylinder hav standing of the invention, however, its ad ing its piston J’ cable connected to each of the vantages and speci?c objects attained with its use, reference should be had to the accompany 60 carriages ortrucks E and EA. As shown, the cylinder J is vertically disposed with its upper ing drawings and descriptive matter in which I end open and with a passage through its lower have diagrammatically illustrated a preferred closed end through which the stem J2 of the pis embodiment of the present invention. ton J’ extends. The lower end of the piston stem Of the drawings: Fig. 1 is a diagrammatic elevation of a desir 65 J2 is connected to one end of a cable K which extends about a guide pulley L, turning about a able form of hot ?nishing apparatus; stationary axis beneath the cylinder J. The end Fig. 2 is a plan view of the portion of the ap of the cable K remote from the cylinder J is con paratus shown in Fig. 1; and nected to an equalizing bar K’ midway between Fig. 3 is a sectional elevation of a control valve. In the embodiment of the invention illustrated 70 the ends of the latter, as shown mast clearly in Fig. 2. The two ends of the bar K’ are similarly diagrammatically in the drawings, the tinned connected to the carriages E and EA at the op plate stock strip A is hot finished as it is being posite sides of the latter. The connection be rapidly moved by feed rolls C through a ver tween each end of the bar K’ and each carriage tical path extending between the feed rolls C and guide rolls B, by the heating action of vertical 75 at thecorresponding side of the latter, comprises 2,409,431: 6 a cable K2 connected to the end. of the ‘bar 1K! and extending under. and thence upward‘ away ment of the‘piston J’ when travel of’ the work strip A is interrupted or is substantially reduced frame pulley LA which is sodiisposed ‘that the in speed so that it‘is then desirable to move the burner walls D and DA far enough away from uprising-end of the cable Kz‘i‘s alongside the-cor responding edge of the vertical portion of the work strip moving upward between the burner wane. ‘Theuprisi-ng end of. each of the two cables K2 is connected to the carriages E and EA by the work strip, to prevent overheating- of the latter.' I,‘ ~ ~Y ‘ The control valve Q may be of any'khown or suitable form adapted to operate as described. corresponding cables M and MA, respectively. ‘ Each cable M extends over-a guide pulley N As shown in Fig. 3, the body of the valve‘ Q coin prises an inlet chamber Q’ in communication mounted on the corresponding carriage support F; From its guide pulley‘ N, each cable M passes with the cylindervJ through the pipe P, andT'a-n outlet chamber Q2 from which oil may pass in a generally horizontal ‘direction toward the freely 'to a receiving receptacle q. The valve rear end of the truck E t'o-which‘it is connected chambers Q’ and Q2 are separated by a partition by a pin E2. Each cable, MA runs over a corre 15 formed with a central circular opening, or port sponding pulley NA mounted on the support F Q3 normally receiving a coaxial cylindrical valve for the carriage EA and is connected to the latter member Q4 of a diameter to ?t snugly in the just as the cable M is connected to the carriage port Q3, so that ‘when the valve member Q4 is E. As shown, each of the cables M and MA in moved downward into its full closing position, eludes a turnbuckle M’ which may be adjusted 20 the upper‘end of the valve member will be to» vary-the distance between» the corresponding within, and will close or substantially close the burner'wall and the work ‘strip maintained in port Q4.‘ The valve member Q4 is formedi‘at its normal operation. ' periphery with a longitudinal V-shaped-slot‘Q5‘, The gravitational bias of each of the carriages which extends from the lower end of ‘the valve E and EA for movement downward and away member to a point some-what below the upper end from the work strip A along its supporting rails F’, tends to maintain the cables K, K2, M and MA taut at all times, and insures suitably rapid of the valve member, and progressively dimin~ movement of each burner wall along its support ing track rails F’ away from the work strip A .' when- permittedby downward movement of the piston ‘J'. Y , . The movements of the‘piston J’ can ‘be ef fected‘ and controlled for the purposes of the present invention in various ways. In the form shown diagrammatically, the piston J’ is nor mally maintained in or- near its position shown in Fig. l by a liquid, preferably oil, in ‘the cyl~ inder J and under sufficient pressure to coun~_ ter-balance the forces acting downwardly on the piston. Those forces comprise the pull of the justment of the‘ valve Q, increasing or decrease in the cylinder J will increase or decrease as needed to vequalize the out?ow with the in?ow cable K, the gravitational bias due to the weight to the cylinderf The position of the piston .J” and therefore‘ the distance between the work strip’and each burner wall, Will thus vary in ac cordance with the changes in position of the ably secured. to the cylinder J by bolts J5; The valve‘. member Q4 when the latter occupies an maximum distance the spring J3 can expand or elongate is ?xed by a retaining bolt J 6 in thread intermediate position. . I ‘ When the travel of the ‘work strip A is inter rupted or ‘its speed decreases below the regula; tion range‘ and the valve member, Q4 is moved upward out “of the portQ3, the oil is permitted to ed engagement with the head J4 and‘ acting be tween the latter and a belleshaped spring fol lower J7, interposed between‘the spring J3 and the piston J. The portionof the cylinder J above the piston J’ is freely open to the external at ' member Q4 will'occupy an intermediate position with such a portion of ‘the groove Q5 within the port ‘Q4, that the throttling effect of the valve member will be so related to the‘ compression of spring J3 and resultant oil pressure beneath the piston J’, that out?ow from ‘the cylinder J through valve Q will be‘ equal in rate to the‘ cyl inder in?ow through the pipe 0. On any ad ‘ing‘its' throttling effect, the pressure of the oil of the piston J’ and its stem J2, and a loading force due to the action of a spring J‘3 acting be tween the piston J and a cross head J4 adjust mosphere through portsJg. ishes in cross-section from its bottom upward. When the speed of the strip A is constant and within its normal operating range,‘ the- valve escape freely from the ‘cylinder J which" then , In the arrangement illustrated, liquid is sup- 55 plied to the cylinder J. by ‘a pipe 0 from a source (not shown) of liquid under a suitable ‘pressure, and the liquid escapes from the cylinder J quickly empties and‘ permits a ‘corresponding rapid downward movement of the piston J", and thereby effects ,a rapid safety movement of each burner Wall away‘fr‘om the work strip. In- the arrangement diagrammatically shown, referring particularly to Fig. 1 the valve member through an outlet pipe P, when and as permitted Q49" is adjusted in automatic accordance with by the adjustment .of a control Valve Q. In the 60 changes“ the traveler the work‘ stripA, ‘by arrangement shown, ‘the supply pipe 0. is re~ means comprising "a centrifugal speed governor stricted at 0' so that» the ‘maximum rate of. ?ow of conventional type and having its lever S’ con through the pipe 0 will be small enough to per ne'bted to the‘ stem, Q6‘ of the valve Q by a link mit the cylinder J. tov empty rapidly when the R-"which includes a turn buckle R’ through which Valve Q is wide open. I In a manner hereinafter described, the valve Qis; adjusted automatically in accordance with 65 the effective lengthof the-‘link can be adjusted. The speed governor S comprises shaft S2 mounted in a support S3 for rotativabut not for variations in the speed of travel of the work longitudinal movement, and comprises centrifu~ strip A, to vary the oil pressure acting on the gal weights S4 link connected to the upper end piston J,’ and thereby adjust the burner walls 70 of the shaft S1 and, link connected to the lower D ,and‘DA toward and away from the work strip . end of a sleeve 55, surrounding and longitudie A‘and from one another through a small work ,nallymovable along, the shaft S2. The sleeve S5 ing range, as the speed of the strip A» varies isformed with a, circumferential groove S-‘iwhich through a relatively small regulation range, and receives lateral, projections S7 carried by the to permit a rapid: and substantial down move 75 forkedlyend of the. lever ,S’ , so that, the; lever 1S.’ 2,409,431 7 turns in the direction to give an opening or a closing adjustment to the valve member Q‘1 as the speed of the shaft S2 decreases or increases. 8 inder under a pressure high enough to appreci ably augment its rate of discharge. The ulti mate operative effect of the last mentioned ad justment of the valve member Q4, is thus to ef As shown, the governor shaft S2 is rotated at fect an immediate movement of each burner wall a speed proportional to the speed of travel of D and DA away from the work strip a distance the Work strip A through a driving connection adequate in extent to prevent injury to the latter comprising a shaft T which is transverse to the on an interruption of, or radical reduction in shaft El2 and has one end connected to the lat speed of the work strip A. ter by bevel gears T’ and has its opposite end As will be apparent to those skilled in the art, connected through bevel gears T2 to one of the 10 the control of the positions of the burner walls feed rolls C. In the contemplated normal operation of the apparatus diagrammatically shown, when the D and DA relative to the work strip A, required in the practice of my method on changes in the work strip speed, which is obtained by the centrifugal speed of travel of the work strip A varies, the governor S effects corresponding adjustments of 15 speed governor S, valve Q, and servomotor J, il lustrated, may be obtained by the use of other the valve Q. An immediate operative e?ect of known or suitable instrumentalities differing an adjustment of the valve Q is to vary the po widely from those last mentioned. sition of the piston J’, and an adjustment in the The multiplicity of individual and individually position of the piston J’ directly varies the dis tance between each of the heating walls D and ~ regulable burners din each heating wall, and the regulable means through which a combustible DA and the adjacent side of the work strip A. mixture of air and gas is supplied to each of said It will now be understood that the mechanism burners in use, permits a ready regulation of just described is operable, while the strip is trav the relative heating effects of di?erent portions eling, to move the heat sources D and DA to ward and from the strip in a normal regulating i of each heating wall as required to insure uni form heating of the work strip. Furthermore, range through distances functionally related to the described combustible mixture supply regulat changes in speed of travel of the work. When the speed of the work strip A is within 7 a regulation range, the body of the valve mem ing provisions permits the overall heating e?ect the minimum pressure required to overcome the rows of burners out of service. of each burner wall to be varied as required by ber Q4 is within the port Q3, and the rate of flow 30 the conditions or” operation. For example, under one operating condition in a particular plant, it permitted by the valve with a given pressure in may be desirable to maintain a regulation work the cylinder J depends on what longitudinal por speed range between limits above and below 600 tion of the valve groove Q5 is within the port feet per minute, and under another operating Q3. The work strip speed range can be varied through wide limits by adjustment of the turn v35 condition to maintain a regulation work speed buckle R’ and the consequent adjustment of the range between limits respectively above and be low a speed of 300 feet per minute. For opera effective length of the link connection between tion with the higher work speed range all of the the governor lever S’ and the valve member Q4. When the work strip speed is within the reg burners in each heating wall may be in use and ulation range determined by the then existing 40 operated at nearly full capacity. For operation adjustment of the turn buckle R’, the position at the lower work speed range, several of the of the piston J’ will vary as the pressure of the manifold supply valves G’ may be closed to there oil in the cylinder J varies through a range above by temporarily put the corresponding horizontal In addition, the piston loading force of the spring J3 when the pressure at which the fuel mixture is supplied to latter is expanded to the full extent permitted the burners remaining in service, may also be ma by the spring follower J7 and its adjustable re terially reduced. taining member J 6. The actual regulation range To appreciate the importance of adequately rapid adjustments of the rate of heat transfer to of piston movement may be varied by the adjust ment of the head J4 and thereby the parts J3, J 7 50 the work from each burner wall, account should and J 6, longitudinally of the cylinder. The mag be taken of the high temperature and high rates nitude of the regulation range of adjustment of of heat liberation involved. Thus, for example, it is reasonable to assume that in hot ?nishing the piston J’ can be varied by adjustment of the a work strip which is 30 inches wide and of aver bolt J6, to vary the maximum distance between the crosshead J4 and follower J". 55 age thickness and which is moved through the ?nishing station at the rate of 600 feet per min The movements of the piston J ' in the cylinder ute, each burner wall may have its burner face J produce corresponding movements of the burner spaced 1 inch from the work, and may include walls D and DA transverse to the work strip A passing them. The relation between any partic 150 burners, and to assume further that the burn ular position of the piston J’ and the correspond 60 ers of each burner wall are collectively supplied with about 30 cubic feet per hour of 500 B. t. u. ing position of either burner wall, may be varied gas mixed or combined with the required amount by the adjustment of the corresponding turn of combustion supporting air. buckle M’ or by an analogous adjustment in the Under the operating conditions just described, effective length of the mechanical connection be 65 the entire burner wall face adjacent the work tween the piston and the burner walls. strip will be incandescent, and the temperature When the work speed decreases below the reg ulation range, ?xed in apparatus of the form shown by the adjustment of the turn buckle R’, the valve member Q4 is moved up out of the port in the combustion chambers of the burners will be about 2400" F. While a portion of the heat liberated in each combustion chamber is radi Q3 thereby permitting a rapid discharge of the 70 ated directly from the burning gases to the work, the relatively high temperatures and large heat oil from the cylinder J’ and a correspondingly storage capacity of the refractory burner walls, rapid downward movement of the piston J '. do not permit regulation of the rate of heat trans The gravitational forces acting downwardly on fer from the burner wall to the work strip rapidly the piston J’ duetto the weight of the piston J ', maintain the oil being discharged from the cyl 75 enough to compensate for rapid variations in the 2,409,431 . work strip speedto be effected by' regulation of v ‘1J0 the rate ‘at which combustible mixture ‘is sup tween said: walls, and means for separately ad justing the dits'ance ‘between ‘each of said faces plied ‘to‘the burner wall burners. ' and said strip. ‘ While in accordance with the provisions of the 8; Apparatus for hot ?nishing tin plate stock statutes, I ‘have illustrated‘ and described the best Cl in‘ the form of a thin steel strip coated with tin, form of embodiment of my invention now known comprising in combination, a pair of refractory to me, it will be apparent to those skilled in the walls each having a hot face adjacent and nor art that changes may be made in the form of mally in close proxmity to the hot face of the the apparatus disclosed without departing from other gas wall, means for maintaining said faces the spirit of my invention, ‘as set forth‘in the 10 at temperatures substantially above the melting appended claims, and that in some cases certain point of tin, means supporting each of said walls features of my invention may be used to advan ‘for movement in a direction toward and away tage without a corresponding‘use of other fea from the ‘other, means gravitationally ‘biasing tures. ‘ , each of said walls for movement away from ‘the Having now described 'my invention, What I 15 other, means ‘for rapidly moving said strip in the claim as new and desire to secure by Letters Pat direction of its length through the space between ent, is: , 1. Apparatus‘ for hot ?nishing'tin‘plate stock in the form of a thin strip having a tin coating, comprising in combination a pair of refractory walls having opposing faces normally in close proximity to each other, means carried by said walls for maintaining said faces at temperatures substantially higher than the melting point of tin, means normally moving said strip rapidly through the space between said walls, and means respon sive to the speed of said strip for increasing the distance between ‘said. faces when the speed of said strip diminishes. 2. Apparatus for hot ?nishing tin plate stock in the form of a thin strip having a tin coating, comprising in combination a pair of refractory walls having opposing faces normally in close proximity to each other, means carried by said walls for maintaining said faces at temperatures , substantially higher than the melting point of tin, means normally moving said strip rapidly said walls, positioning means normally operative to prevent movement of said walls away-from one another, and means responsive to the speed of said strip for rendering said positioning means inoperative on a predetermined decrease in the speed of said strip. 9. Apparatus for hot ?nishing a coating of tin on one side of a thin steel strip, comprising in combination means for moving said strip at high speed in the direction of its length along a prede termined ?nishing path, a refractory wall having a hot face and at one side of said path at which said coating ‘is ‘exposed, means carried by said Wall for heating said face to a temperature sub stanti'ally higher than the melting point of tin, and means responsive to the speed of‘sald strip for increasing the distance between said face and path on a decrease in the speed of said strip while the latter is moving past said refractory-wall, said heating means during such increase in distance between its face and the path being ‘capable of heating the strip to effect ?nishing of ‘said coat~ through the space between said walls, and means responsive to the speed of said strip for increas ing thereon. ' ing and decreasing the distance between said 40 10. Apparatus for ‘hot ?nishing a coating of faces as the speed of said strip decreases‘and in tin on one side of a thin ‘steel strip comprising in creases through a regulation range and rapidly combination means for‘moving said strip rapidly and substantially increasing said distance when in the direction of its length along a predeter said speed decreases below said range. mined ?nishing path, a refractory wall at the side 3. Apparatus for hot ?nishing tin plate stock of said path at which said coating is exposed, in the form of a thin strip having a tin coating, comprising in combination a pair of refractory walls having opposing faces in close proximity to each other, means carried by said walls for main means carried by said wall for heating said face taining said faces at temperatures substantially higher than the melting point of tin, means mov ing said strip rapidly through the space between said Walls, and means responsive to the speed of said strip for increasing and decreasing the dis tance between said faces as the speed of said strip ' decreases and increases through a regulation range. toa temperature substantially higher than the melting point of tin, and means responsive to changes in speed of said strip for increasing and decreasing the distance between said face and patlias the speed of said strip decreases and in creases while traveling past said refractory well, said heating means during such increase and de crease in distance between its‘face and said path being capable of heating the strip to effect ?nish ing of said coating thereon. 4. Apparatus as speci?ed‘ in claim 3, including means for varying the magnitude of the strip 11. In the art of heating work with the aid of a high‘ temperature source of heat in which the work is moved past such source of heat, the im speed regulating range. provement which comprises varying the position ‘ 5. Apparatus as speci?ed in claim 3, including means for varying the upper and lower limits of said strip speed regulating range. 6. Apparatus as speci?ed‘in claim‘3, including means for varying the distance maintained be? tween said faces at a given speed within said speed regulating range. ' V ’ Apparatus for hot ?nishing tin plate stock in the form of a thin strip having a tin coating, comprising in combination a pair of refractory walls having opposing faces‘in close proximity to each other, means carried by said walls for main taining said faces at temperatures substantially higher than the melting point of tin, means for moving said strip rapidly through the ‘space be of said source of heat with respect to the work, while the latter is being heated, responsive to changes in the rate of movement of the work in a normal'regulating range between a ?rst speed and second higher speed of the Work, such varia tions in the position of said source of heat with respect to the work being effected- by“relative movement therebetween through distances functionally related to‘ changes in the rate of move ment of the work, and adjusting the position of said source of heat with respect to the work so that the work will not be injured by heat from said source of heat when the rate of ‘movement of the work falls below the ?rst speed in said normal regulating range. 2,409,431 11 12 17. In the art of heating work of elongated ex 12. The combination of means for heating work, means for moving said work past said heat tent, the improvement which comprises rapidly ing means in a ?xed path of movement for pro moving the work in a ?xed path of movement, progressively applying through a gaseous medium gressively heating successive longitudinal por tions of the work, said heating means being mov able toward and from the work, and mechanism responsive to decrease and increase in the rate of movement of the work in a normal regulating range between a ?rst speed and second higher speed of the work for moving said heating means from and toward the work, respectively, said mechanism including means operable when the rate of movement of the work falls below the ?rst speed in said normal regulating range for moving said heating means such a distance from the work that the latter will not be injured by heat from said heating means. 13. The combination with burner structure for producing gaseous heat to heat work, of means for moving the work past the burner structure for progressively heating successive portions of the work, the burner structure being movable to ward and from the work, and means operable re to successive longitudinal portions of the work, when the work is traveling in said path of move ment at a predetermined speed, a source of heat which is at a temperature much higher than the melting point of work and su?iciently close to the work so as to melt the surface thereof, moving the source of heat toward and from the work through distances functionally related to increase and de crease, respectively, in change of speed of the work from the predetermined speed in a normal range of speed variations of the work so as to effect melting of the surface in such normal speed range of the work, and, when the speed of travel of the work falls below the lower limit in the nor mal speed range, moving the source of heat from the Work such a distance that undesirable over heating of the work is avoided. 18. In the art of heating the opposing surfaces of work of elongated extent, which comprises rapidly moving the work in a ?xed path of move sponsive to changes in the rate of movement of the work, while the latter is being heated by the 25 ment, progressively applying through a gaseous medium to successive longitudinal portions of burner structure, for moving the burner struc each surface, when the work is traveling in said ture toward and from the work to control heating path of movement at a predetermined speed, a of the work, said last-mentioned means being constructed and arranged to move the burner source of heat which is at a temperature much structure through distances functionally related higher than the melting point of the work and to changes in the rate of movement of the work. 14. The combination of means for heating work, means for causing the work to travel past the heating means for progressively heating suc cessive portions of the work, the heating means 35 being movable from and toward the work, mech su?iciently close to the work so as to effect melt ing of the opposing surfaces thereof, and moving the sources of heat toward and from the work through distances functionally related to increase and decrease, respectively, in change of speed of the work from the predetermined speed so as to effect melting of the opposing surfaces with changes in speed of travel of the work from the anism operable while the work is traveling for moving the heating means from and toward the predetermined speed. work through distances functionally related to changes in speed of travel of the work, the heat 40 19. In the art of heating work, the improve ing means during such movement effected by the ment which comprises moving the work in a ?xed mechanism being capable of heating the work, path of movement past a source of heat for ap and said mechanism including means to cause plying heat through a gaseous medium to succes movement of the heating means from the work, sive areas of the work, and, while heat is being when the traveling movement of the work is 45 so applied to the work, varying the position of the stopped, through a distance which is not func source of heat with respect to the work respon tionally related to change in speed of travel of sive to changes in the rate of movement of the the work to prevent the latter being injured by work, such variations in the position of the source heating by the heating means. of heat with respect to the Work being effected 15. The combination of means for heating 50 by relative movement therebetween through dis tances functionally related to changes in the rate work, means for causing the work to travel past the heating means in a ?xed path of movement of movement of the work. 20. In the art of heating work, the improve for progressively heating successive portions of ment which comprises moving the work in a ?xed the work, the heating means being movable from and toward the work, and mechanism operable - path of movement past a source of heat, main taining the heat source a de?nite distance with while the work is traveling for moving the heat ing means through distances functionally related respect to the work for movement of the latter at a predetermined speed so as to apply heat through to changes in speed of travel of the work, the a gaseous medium to the work to heat successive heating means during such movement effected by areas thereof approximately to the same desired the mechanism being capable of heating the high temperature, and, while heat is being so ap work. 16. In the art of heating work of elongated ex plied to the work, moving the heat source to ward and from the work responsive to increase tent, the improvement which comprises rapidly and decrease, respectively, in change of speed of moving the work in a ?xed path of movement, the work from the predetermined speed so as to progressively applying through a gaseous medium heat successive areas of the work approximately to successive longitudinal portions of the work, to said desired high temperature upon changes when the latter is traveling in said path of move in speed of the work from the predetermined ment at a de?nite speed, a source of heat which speed. is at a temperature much higher than the melt ing point of the work and sufficiently close to the 70 21. In the art of heating work, the improve ment which comprises moving the work in a ?xed work to melt the surface thereof, and, while the source of heat is being so applied to the rapidly path of movement past the source of heat, main taining the heat source a de?nite distance with moving work, moving the heat source from the respect to the work for movement of the latter work responsive to decrease in speed of the work from the de?nite speed. 75 it‘? a predetermined speed so as to apply heat 2,409,431 13 14 through a gaseous medium to the work to heat successive areas thereof approximately to the same desired high temperature, and, while heat is normal regulating range between a ?rst speed and a second higher speed so as to control the normal heating of the work, and, when the speed of travel of the work falls below the ?rst speed source toward and from the work responsive to Cl in the normal regulating range, moving the heat being so applied to the work, moving the heat increase and decrease, respectively, in change of speed of the work from the predetermined speed source a sui?cient distance from the work with out regard to the normal heating of the work so as to prevent undesirable overheating of the work. 23. In the art of heating work with the aid of approximately to said desired high temperature 10 a high temperature source of heat possessing such operating characteristics that residual heat in such normal speed range of the Work, and, is produced thereby after the supply of heat pro when the speed of travel of the work falls below ducing medium thereto is substantially reduced, the lower limit in the normal speed range, mov~ the improvement which comprises moving the ing the heat source from the work such a dis tance that undesirable overheating of the work is 15 work at a rate of speed in a normal speed range past such source of heat for applying heat to suc avoided. ' cessive areas of the work, and, while the work is 22. In the art of heating work, the improve openly exposed to the source of heat, increasing ment which comprises moving the work in a ?xed the distance between the source of heat and the path of movement past the source of heat for work sui?ciently to prevent undesirable overheat applying heat, to successive areas of the work, ing of the latter when the speed of travel of the and, while heat is being so applied to the work, work falls below the normal speed range. moving the heat source with respect to the work FREDERIC O. HESS. responsive to changes in speed of the work in a in a normal range of speed variations of the work so as to heat successive areas of the work Certi?cate of Correction Patent N0. 2,409,431. FREDERIO O. HESS October 15,. 1946. It is hereby certi?ed that errors appear in the printed speci?cation of the above numbered patent_requiring correction as follows: Column 4, line 70, for “mast” read most; column 5, hne _14, before “truck” insert carriage or; column 10, line 2, claim 7, for “d1tsance” ‘read dzsta'nce; line 8, claim 8, for “proxmlty” read proximity; column 11, comma “respectwely,” insert while the latter is LESLIE FRAZER, , v ’ First Assistant Commissioner of Patents.