US2918069A - Sealing rolls for tanks - Google Patents

Description

Dec. 22, 1959 o. J. BROWN, JR, ETAL 2,918,069

SEALING ROLLS FOR TANKS 2 Sheets-Sheet 1 'Filed Jan. 15, 1958 R SJ M 1 T N W mo R 8 l R BY KENNETH D. MILLER SR.

AT ORNEYS Dec. 22, 1959 o. J. BROWN, JR., ETAL 2,918,069

' SEALING ROLLS FOR TANKS Filed Jan. 15, 1958 2 Sheets-Sheet 2 s 58 FIG.3

e-rfii I INVENTORS I 74 OLIVER J. BROWN JR.

2 W Y KENNETH 0. MILLER SR. g q t 2 10 AT ORNEDY 2,918,069 SEALING ROLLS FORTANKS Oliver J. Brown, Jr., Kenilworth, and Kenneth D. Miller,

-Sr., Matawan, N.J., assignors to Hanson-Van Winkle- Munning Company, Matawan, N.J., a corporation of New Jersey Application January 15, 1958, Serial No. 709,077

11 Claims. (Cl. 134-122) The present invention relates to tanks for treating moving web material, and more particularly to an improved arrangement of sealing rolls, used at the ends of processing tanks, enabling web material to be passed through the wall of a tank below the level of treating solution in the tank- In the processing of a metal web, as by caustic or acid treatment, electroplating, or the like, the web may be moved continuously through one or more tanks containing treating solutions. Conventionally, the web enters or is removed from a tank, at the top, near its ends. However, in the continuous processing of elongated webs, such as strip orcoiled sheet, the conventional handling involves waste tank length and excessive spacing between successive treating tanks.

The present invention provides a novel arrangement of sealing rolls, for use particularly with tanks containing corrosive solutions, whereby web material may be passed through the wall of a tank below the level of the solution therein, to make full use of tank length and, wherea plurality of successive tanks are used in the treatment, to minimize the distance between successive tanks. In accordance with the invention, a pair of sealing rolls and the mounting and driving means therefor are formed of or covered with materials not subject to attack by the corrosive treating solutions, and the parts of the assembly are constructed and arranged to advantage, so that the use of high cost materials, such as stainless steel, is kept at a minimum.

'One of the more specific features of the invention, is the provision of a novel arrangement for mounting and driving a pair of sealing rolls, whereby the mounting and driving means is not subject to attack by corrosive solution splashed from the tank or present as vapor in the air. Moreover, the new arrangement is such that the roll mounting and driving means may be immersed in the corrosive treating solution, where necessary or desirable. For a better understanding of the invention, reference may be made to the accompanying drawings, in which:

, Fig. l is a plan view of an end portion of a treating tank incorporating the sealing roll arrangement of the invention;

Fig. 2 is a sectional view taken on line 22 of Fig. 1;

Figs. 3-5 are sectional views taken on lines 3-3, 4-4 and 5-5 respectively of Fig. 2; and

Fig. 6 is a fragmentary perspective view of a sealing roll incorporated in the apparatus of the invention with parts broken away.

In the illustrated apparatus, which may be part of an electroplating installation, for example, a tank 10 is formed of metal plates provided with a coating 11 of rubber or other inert material, the term inert as used herein meaning not subject to attack by treating solutions to be held in the tank. The tank has spaced side walls 12, 13 and end walls, one of which is shown at 14.

In the illustrated form of the invention, the end wall 14 has sections 15, 16 extending inwardly from the side walls, sections 17, 18 extending parallel to the side walls United States Patent 0 2,918,069 Patented Dec. '22, 1959 and a section 19 connecting the outer ends of the p'arallel sections 17, 18. The sections 1719 form a wall projection 20, which extends outward from the end of the tank and has a width less than that of the tank. The upper portion of the connecting wall section 19 is cut away, as are upper portions of the parallel wall sections 17, 18, to form a recess 21 in the end wall projection, as best shown in Fig. 4.

Extending across and partly closing off the recess 21 are sealing rolls 22, 23, which are journaled at their ends, by means to be described, and form a nip 24 below the contemplated level of treating solution to be held in the tank. The sealing rolls are substantially identical in form and, hence, only one will be described in detailwith reference being made to corresponding elements of the other roll by primed numerals.

In accordance with one aspect of the invention, the roll 22 comprises a metal core 25, formed of metal, such as steel, which is of substantially uniform diameter between points adjacent its ends but has end portions 26 of reduced diameter forming shoulders 27 adjacent each end. Received over the core 25 and extending between the shoulders 27 is a casing 28 formed of material, such as rubber, which is resilient and inert to the treating solu: tion. The casing 28 has a central portion 29 of uniform diameter and end portions 30 of reduced diameter forming shoulders 31, and the extreme ends 32 of the casing are bent inwardly to overlie the shoulders 27 of the core. At one end (Fig. 2) the reduced diameter end of the core 25 has successively reduced sections 33, 34 forming a shoulder 35 spaced from the shoulder 27.

A washer 36, formed of inert, resilient material, such as rubber, is received over the reduced section 33 and is positioned adjacent the inturned end or lip 32 of the casing. A gear 37, of suitable inert plastic material, such as polyvinyl chloride, is also received over the reduced section 33, outside the washer 36, and is keyed to the core by a key 38. A second rubber washer 39 is received over the reduced core section 34 outside the gear 37, so that the gear and the washers 36, 39, when placed under axial compression, seal the portion of the core 25 surrounded thereby.

Received over the outer reduced portion 34 of the core is a bearing sleeve 40, which may be formed of stainless steel, for example, and has a radial flange 41 adapted to press against the outside washer 39. The sleeve 40 is of such length that the outer end thereof is substantially flush with the end of the core, and the sleeve is held in place and put under axial compression by a stainless steel retaining plate 42 held in place by stainless steel screws 43. A rubber washer 44 is interposed between the plate 42 and the end of the sleeve 40, to seal oil the end of the core 25.

It will be understood that the opposite ends of the sealing roll 22 are of similar construction, except that the gear 37 and special facilities for its mountingand sealing are omitted at one end. The arrangement is such, in accordance with the invention, that the steel core 25 is wholly sealed within a protective casing assembly ofinert materials, such as rubber, plastic and stainless steel, with stainless steel components being held at a practical minimum.

The sealing rolls 22, 23 are journaled at their opposite ends by hearing blocks 45, 45' and washers 46, 46, formed of a suitable inert, self-lubricating material, such as a graphite-base metal compound. The bearing blocks 45, 45' are advantageously of square or rectangular outline and have central openings for receiving the bearing sleeves 40, 40'. And, in the illustrated form of the in vention, the retaining plates 42, 42', at the ends ,of the rolls, are of greater diameter than the bearing openings, so that the bearing blocks and sealing'rolls are locked 3 in assembled relation, although relative rotary motion and limited axial movement is provided.

Advantageously, the bearing blocks 45, 45' are sup- .ported in frames 47 comprising vertically disposed channel members 48, provided with laterally extending arms 49, 50 at their upper and lower ends respectively, and covered throughout with a protective coating 51 of rubher or other inert material. Secured to the lower channel arms 50, by means of stainless steel bolts 52, and extending across the open lower end of the channels 48, are supporting plates 53, provided with inert coatings 54. The bearing blocks 45 rest upon the plates 53 (Fig. 3) and support the lower sealing roll 23 in the lower portion of the tank wall recess 21. The upper roll 22 is supported by the lower roll 23, and its bearing blocks 45 are held in proper alignment by the channels 48. The frames 47 are supported on projecting end portions 55, 56 of the tank side walls, by lugs 57, the frames being secured to the lugs by stainless steel bolts 58.

Where desirable or expedient, the sealing rolls may be driven through a system including a plastic gear 59, shaft 60, and drive chain 61. The drive system may be synchronized with other processing equipment, in the usual manner, where the processing tank forms part of a comprehensive treating installation.

As may be observed in Fig. 2, the central portions of the sealing rolls, defined by the large diameter portions of casings 28, 28', form a nip 24 which prevents the flow of treating solution between the central portions of the rolls, even though the nip is below the solution level. To provide a liquid seal adjacent the roll ends, there are provided sealing plates 62, formed of suitable inert material, such as plastic, which are secured to the spaced end wall sections 17, 18 by stainless steel bolts 63 and extend lengthwise of the tank toward the sealing rolls. In the illustrated apparatus, the outer edges of the plates 62 are provided with recesses 64, 64', of generally semi-circular form, which are received about the roll cores 25, 25 and reduced diameter portions of the casings 28, 28', adjacent the casing shoulders 31, 31'.

Positioned between the sealing plates 62 and the casing shoulders 31, 31' are pairs of sealing washers 64, 65 and 64, 65', which are of substantially the same diameter as the central portions of the sealing rolls. The washers 65, 65 are formed of inert rubber material and are positioned flat against the casing shoulders 31, 31, while the washers 64, 64 are advantageously formed of Teflon (tetrafluoroethylene) and are in flat contact, on one side, with washers 65, 65' and, on the other side, with the sealing plates 62.

In accordance with one aspect of the invention, the sealing plates 62 press inwardly upon the sealing washers 64, 65 and 64', 65 to maintain an effective liquid seal adjacent the ends of the sealing rolls. The rubber Washers 65, 65 are adapted to rotate with the rolls 22, 23 while the Teflon washers 64, 64 are held stationary by the sealing plates 62. Relative movement thus takes place between the rubber and Teflon washers, under low friction conditions, resulting in reduced maintenance problems. However, either or both of the sealing washers may be readily replaced from time to time, as necessary.

To maintain the sealing washers under sufficient axial pressure to assure a good seal, it is advantageous to provide adjustable pressure screws 66, 67 arranged to press inwardly upon the end edges of the sealing plates 62. The screws 66 may be mounted in brackets 63 supported on the tank wall extensions 55, 56, while the screws 67 may be mounted in brackets 69 mounted on the connecting wall section 19. The screws 66, 67 may be adjusted from time to time, if necessary, to take up for wear in the sealing washers.

A liquid seal is provided along the bottom edge of the lower sealing roll 23 by means of a doctor blade 70, advantageously formed of a rubber laminant, which is held in sealing engagement with the central portion of the roll casing by a mount 71 (Fig. 5) comprising rubber clamping blocks '72, 73 and a clamping bar 74 formed of inert, rigid material, such as plastic or stainless steel. The clamping blocks and bar are secured to the connecting wall 19 by stainless steel bolts 75, selected ones of which may be used for attaching the bolt brackets 69. As indicated in Fig. 2, the doctor blade 70 is provided with vertically elongated Slots 76 for receiving the clamping bolts '75, whereby the blade may be adjusted vertically during assembly and to accommodate for wear.

In the illustrated form of the invention, the length of the rubber clamping blocks 72, 73 is substantially equal to the combined length of the central portion of the sealing roll 23 and the pairs of sealing washers 64', 65', so that the lower portions of the sealing plates press against the ends of the clamping blocks, to form a seal. And adequate sealing pressure is provided by locating the adjusting screws 67 adjacent the ends of the clamping blocks.

When the apparatus is in operation, the tank 10 is filled to a level above the roll nip 24 with treating solution and a web 77 of material, such as metal strip or sheet, is passed through the solution and leaves the tank between the sealing rolls. The resilient material of the roll casings deforms sufiiciently to accommodate the web 77 while maintaining the roll nip closed on each side of the web. Generally, the sealing rolls are driven in synchronism with movement of the web 77, by the external drive system comprising gears 37, 37, 59, shaft 60 and chain 61, but in appropriate cases, the sealing rolls may be driven by the contact with the web.

One of the advantageous features of the new apparatus is that all parts of the apparatus which are exposed to the treating solution, or which may be splashed by the solution or exposed to its vapors, are formed of inert materials, and the design of the apparatus is such that the inert materials are largely of a low cost variety, such as rubber and plastics. Further, in this respect, while in the illustrated apparatus the ends of the sealing rolls and the driving gears are positioned outside the tank body, the apparatus may be so designed that the rolls and drive system are immersed in the treating solution.

We claim:

1. In combination with a tank for holding a treating solution, a pair of sealing rolls journaled adjacent one end of the tank and having a nip below the top of the tank, the central portions of the rolls being exposed to the interior of the tank and forming, at least in effect, part of a wall of the tank, the rolls having end portions of reduced diameter forming spaced shoulders at the ends of the central portions, at least the surfaces of the central portions and shoulders being formed of inert resilient material, pairs of washers formed of inert resilient material received over the end portions of the rolls adjacent the shoulders, and sealing plates forming part of the tank wall and having portions contoured to be received about the end portions of the rolls for pressing the pairs of washers toward the respective shoulders.

2. The apparatus of claim 1, in which the resilient surface material of the rolls is rubber, one of the washers of each pair is formed of rubber and seats against a shoulder of a roll, the other washer of each pair is formed of Teflon, and the other washer seats against the rubber washer and is acted upon by a sealing plate.

3. The apparatus of claim 1, in which the sealing rolls have metal cores, and outer casings of inert resilient material cover the central portions of the rolls and form the shoulders.

4 The apparatus of claim 3, in which the metal cores are of substantially uniform diameter throughout the central portions thereof and for distances beyond the central portions, and the casings extend throughout the entire uniform diameter portions of the rolls and have portions of reduced diameter adjacent their ends to form the shoulders.

5. The apparatus of claim 1, in which the sealing rolls have metal cores and outer casings of inert resilient material extending substantially throughout the length of the cores but terminating short of the ends thereof, the cores have shoulders adjacent their ends, and members formed of inert material are received over the ends of the core and press end portions of the casings against the core shoulders to seal the cores.

6. The apparatus of claim 5, in which the inert members comprise, at least in part, bearing sleeves formed of inert metal.

7. The apparatus of claim 1, in which the rolls have bearing sleeves of inert metal adjacent their ends, and the sleeves are journaled in self-lubricating bearing blocks of graphite-metal composition.

8. The apparatus of claim 1, in which the rolls are journaled at their ends in bearing blocks of inert material, and the bearing blocks are held in frames supported by walls of the tank and covered with inert material.

9. The apparatus of claim 8, in which the frames comprise vertically disposed channel members having laterally extending arms adjacent each end, a plate is secured to the arms at the lower end of each channel to form bottom supports for hearing blocks, and means are provided for engaging the arms at upper ends of the channels for supporting the frames.

10. The apparatus of claim 1, in which the tank has spaced side walls and an end wall, the end wall has sections extending at right angles to the side walls and spaced sections extending parallel to the side walls and forming with other portions of the end wall a central wall projection, the central wall projection has an opening therein closed in part by the sealing rolls, end portions of the rolls extend outward beyond the spaced wall sections, and the rolls are journaled at their end portions.

11. The apparatus of claim 1, in which the sealing plates are mounted on the tank wall at points spaced from the sealing rolls, and adjustable members press against the sealing plates adjacent the rolls to maintain the plates in sealing relation.

References Cited in the file of this patent UNITED STATES PATENTS 654,194 Twohy July 24, 1900 2,255,859 Quigley Sept. 16, 1941 2,393,203 Tarbell Jan. 15, 1946 2,628,627 Hutf Feb. 17, 1953 2,650,603 Howes Sept. 1, 1953 2,781,535 Phillips Feb. 19, 1957 OTHER REFERENCES Zimmerman and Lavine: Handbook of Material Trade Names, 1953 edition, page 558, Industrial Research Serv., Dover, NH.

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