US469925A - Thomas l - Google Patents

Description

(No Model.) 2 Sheets-Sheet 1.

T. L. THOMAS'& J. B. HILLMAN. PROCESS OF GALVANIZING METAL TUBES 0R BARS.

No. 469,925. Patented Mar. 1, 1892.

, 2 Sheets-Sheet 2. T. L. THOMAS & J. B. HILLMAN. PROCESS OF GALVANIZING METAL TUBES OR BARS.

No. 469,925. Patented Mar. 1, 1892.

UNITED STATES PATENT FFICE;

THOMAS L. THOMAS AND JOSEPH BEARD IIILLMAN, OF PRINCES END,

' ENGLAND.

PROCESS OF GALVANIZING METAL TUBES OR BARS.

SPECIFICATION forming part of Letters Patent No. 469,925, dated March 1, 1892.

Application filed December 6, 1890. Serial No. 373,732. (No model.) Patented in Germany a i' 23, 1888, No. 46,301, and

in England June 3, 1890, No.8,572.

To all whom it may concern:

Be it known that we, .THOMAS LESTER THOMAS, washer and axle-plate manufacturer, and JOSEPH BEARD HILLMAN, galvanizing-works manager, both residing at Princes End, in the county of Statford,England,have invented certain new and useful Improvements in or Relating to the Art or Process of Galvanizing Metal Tubes and Bars and in Means or Appliances for use Therein or Be lating Thereto, (for a part of which invention a patent was obtained in Germany in the name of Francken, No. 46,301, bearing date Februmy 23, 1888, and in Great Britain in the name of Thomas Lester Thomas, No. 8,572, hearing date June 3, 1890,) of which the following is a specification.

Our invention relates to the galvanizing of metal tubes and bars, and has for its object to facilitate the process thereof, to give a uniform coating of zinc, and thereby avoid the waste of such metal which results from the uneven coating which is producedtin the ordinary method of galvanizing such articles, and to give a greatly-improved surface.

According to the ordinary process of galvanizin g metal tubes and bars they are first dipped in the bath of molten spelter and are then slowly drawn up slantwise through a special fiux,'(formed by constantly adding new or fresh ammonia to the surface of the molten metal at the drawing-out end of the bath,) being at the same time turned slowly, with the object of drawing off the superfluous spelter-and leaving a uniformly-coated surface. Such tubes and bars are then laid on fine supporting-edges and rolled or turned to and fro to maintain a uniform coating. \Vhen the coating is set, the articles are dipped in a water bath. This process is,however, tedious and requires considerable skill in manipulation, and the coating of spelter (zinc) is not reallyuniform, and considerable waste results. Moreover, the surface is' not'as smooth and finished as is frequently desired. Now according to this invention the tubes and bars are first dipped in the bath of molten spelter and are then withdrawn therefrom as quickly as may be convenient, regardless of the quantit-y or unevenness of the coating metal adhering thereto and without turning them, as in the ordinary process. As each tube or bar is being drawn out slantwise from the bath the upper end is entered between asbestus dies, which are then closed around it, and the tube or bar is drawn through such dies, whereby the coating metal is evenly distributed over the surface thereof and thesurplus metal is wiped off, the action of the dies producing, also, a greatly-improved surface of thecoating metal. Thetubesor bars are dipped in a water bath immediately after they have been drawn through the dies, and the rolling bove described, as practiced in the'ordinary process, is, according to this invention, entirely dispensed with, the operation of the dies rendering it quite unnecessary. The articles are withdrawn from the bath through the or dinary flux, as it is not necessary to add new or fresh ammonia through which to withdraw them, the even distribution of the coating metal and the wiping the surplus therefrom being performed entirely by the dies. A con siderable saving in flux is thus effected.

This invention is illustrated by the accompanying drawings, in which Figure 1 is a front elevation of the ashestus dies and mechanism by which they are operated, and shows such mechanism to be mounted in position upon the bath, the upper portion of one end of which is shown in section. Fig. 2 is a plan of Fig. 1. Fig. 3 is a longitudinal section taken on line x w of Fig. 1. Fig. 4 is a detached front view of the bottom die hereinafter described, and Fig. 4 a corresponding view of a double-notched die. Fig. 5 is a longitudinal section (drawn to a reduced scale and broken in length for convenience of illustration) through the bath, dies, and apparatus by which they are operated, and through the inclined platform, hereinafter described. Fig, 6 isa frontelevation of a modified form of apparatus for carrying and operating the asbestus dies, and Fig. 7 is a plan of Fig. (5. I

Referring, first, to the form of apparatus shown in Figs. 1, 2, 3, 4, and 5, an angle-plate B, having a base-plate a. and vertical member b, is bolted through such base-plate to the .top of the bath A, which holds the molten galvanizing metal, and in such position near the end of the bath, as shown, that the dies hereinafter described are over a portion of the interior of the bath, into which, therefore, the molten metal can run as it is wiped ed by the operation of the dies. Near each end of the member b of the angle-plate is bolted a pair of guide-standards 0, one on each side of the member I), a space being left between them above such member,- as shown clearly moreespeoially in sectional elevation, Fig. 3. Fillets d project, preferably, from the faces of the member 1/ across each edge of each standard 0 to act as joggles for keeping the standards in position edgewise or sidewise. Between the one pair of standards a is pivoted, by means of a pin t, a lever C. This lever passes between the other pair of standards and terminates in a handle e and is extended beyond its fulcrum at the other end, the extended portion carrying a counterbalanoe-weight f. The lower asbestus die 9 is carried at the outer face of the member b of the angle-plate B by being placed against such face and held thereto by a bar h, which is bolted by means of bolts 2'40 the member I). This die projects above the top of the member 37 and has a notch r of the width of the tubes or bars to be wiped formed in its upper edge, along which the tubes or bars are passed as they are drawn through the dies. The notch is of a semicircular shape at bottom, as shown, when for use for tubes or round bars, but is carried up straight at the sides to give it a somewhat greater depth than that of'the semicircle. .As the upper portion of this die is shown by broken lines in Fig. 1, the detached view, Fig. 4, is given thereof,

. so as to clearly show the shape of the notch.

The top die j, having a notch s in the lower edge thereof corresponding to the notch r, is.

of the same shape as the bottom die g. This die is carried by the lever C, being placed against theforward face thereof and held by a bar It, bolted to the lever by means of bolts 1. There is thus, as will be cle'arlyseen, more especially by reference to Fig. 3,. some space between the planes of those faces of the dies position indicated by broken lines, Fig. 1,

when the same is not held down by: hand or by the pin 0, hereinafter described, and the chain m, which is attached at one end to the angle-plate B and at the other to the. lever C, prevents the lever from being tilted up by the weight 1- beyond any desired point. The lower die is stationary, and, when a tube or bar is not being drawn through the dies the upper die is in the position shown by broken lines, Fig. 1, the lever being tilted up. When a tube :or bar n, Fig. 5, is raised up slantwise from the bath A,its'end which is the nearerv to the dies is grasped in a pair of tongs passed through between'the open dies by an attendant who stands uponthe inclined platform D.

The attendant-, then pulls the tube forward,

so as to bring its end between the dies, and .an attendant immediately brings down, by means of the handle 6, the upper die j upon the top of the tube or bar, whereupon the attendant upon the platform D draws such tube or bar in an inclined position through the dies, himself Walking up the platform D for this purpose. The tube or bar is put direct into a bath of water immediatelyit has passed from the dies. There is nothing unusual in the platform D. It is what is commonly employed in the galvanizing of tubes and bars in order to enable the attendant to properly withdraw them from the bath. As the notches in the dies are somewhat deeper than the halfdiameter of the tubes or bars, the edges of the dies overlap, as shown in Figs. 1 and 3, when in operation; The drawingof the tubesthrough the dies tends,.of course, to wear the notches deeper, and it is necessary, therefore, even if the notches in the dies are originally formed only half the diameter of thetubes or bars in depth, that the dies should be the one forward of the other, so that as wear takes place the lower edge of the one die may be moved down below the upper edge of the other, and when the notches are originally formed deeper than the half-diameter of the tubes or bars for which they are to be used, as is preferred, for the purpose of more effectually wiping the entire surfaces thereof, the dies overlap one another from the commencement of their operation; The asbestus isof a somewhat yielding nature, and the one die tends, therefore, to be bent somewhat toward the other as the tubes or bars are drawn through them, and thus it is necessary to place the dies with sufficient space between the, planes of their faces which are toward one another to prevent the upper die catching on the lower as it is brought down aftera tube or bar has been placed between the dies. The dies can be readily adjusted in position as wear takes place by first slackening the'bolts by which they are held to the angle-plate and lever, respectively, then moving the dies into the required position and retightenin-g the bolts. A considerable adj ustment in the relative position of the dies may, however, be conveniently given by lowering the lever-fulcrum, and the position of the dies in their holders need not be altered till the lever-fulcrum has been moved down as faras is convenient. A number of holes are provided. in the pair of standards 0, to which thelever is fulcrumed, to permit of the position of its fulcrum being altered as required. A portion uaof the upper inner edge. of the member I) of the angleplat-e B is chamfered off, as shown, to allow into the bath. For bars of other section than round the notches are of course altered in shape to suit the dilference in section.

For convenience insettiug the dies a peg o is pushed through one of a number of holes formed in one of the pairs of standards a and IIO immediately over the top of the lever, in order to keep the lever in the position into which it is intended to be moved to bring the dies into operation. 7

Two or more pairs of dies for difierent sizes of tubes or bars may be carried by one apparatus, or the same pair of dies may be provided with two or more pairs of dilferentsized notches, as shown in the case of the detached view of the lower die g, Fig. 4 and thus batches of ditferent sizes of tubes or bars may be operated upon without changing the dies.

Referring to the modification shown by Figs. 6 and 7, it will be seen that the dies j and g are carried, respectively, in the upper and lower jaws of a pair of tongs E. Each die is fixed by being placed against the inner face of the jaw and held by a plate to at its opposite side, which is fixed by bolts to the jaw.- The tongs are suspended by means of a D-liuk p from a chain q. The end of a set-pin g which is screwed through one lever or handle of the tongs, acts as a stop against the other lever and fixes the point to which the levers may be brought toward one another, and thus the set-pin may be used to maintain the jaws in proper position (as the levers are pressed toward one another) while the dies are set in place.

\Ve are well aware that in tinning continuous lengths of slender and flexible wire it is a common practice to lead the wire from the path of' molten metal through wipers of soft material, one of which is movable. This we do not claim. I

We are also aware that in such apparatuses it has been the practice to keep the upper wiper wet, and this we do not claim.

' Our apparatus and method deals with comparatively heavy and rigid bars in comparatively short lengths, each of which short tubes or bars must be seized and placed in the dies,

so that it may be drawn therethrough, and our apparatus is designed to facilitate this, the lever C being arranged transversely of the path of the tube that is being drawn through the dies and of the axis of the dies and adapted to open the dies in such a way that the movable die will not move toward and from. the face of the non-movable die and that the end of the tube may be conveniently inserted between the. dies when they are open. The tube or bar is not wetted simultaneously with the wiping, but after the tube has passed through the dies and been removed therefrom. There is, however, no intermediate treatment between the wiping and plunging into the water.

What we claim as our invention, and desire \to secure by Letters Patent, is-

1. The herein-described improvement in the art of galvanizing tubes and bars of metal, which consists in first dipping the tube or bar into a bath of molten coating metal, then drawing it through an embracing-wiper of asbestus or similar soft refractory material, and then putting it after it leaves the wiper directly into water, substantially as and for the purposes set forth.

2. As a' means for wipinggalvanized tubes or bars, the combination, with a stationary die, of a pivoted lever arranged over said die, a die carried by said lever, and a counterweight on said lever adapted to raise said lever and hold the dies open normally, substantially as set forth.

In witness whereof we have hereunto signed our names in the presence of two subscribing witnesses.

THOMAS L. THOMAS. JOSEPH BEARD HILLMAN.

. Witnesses:

STEPHEN WATKINS, JOHN NEVE.

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