US2221811A

US2221811A - Method of and apparatus for cleaning and pickling metal

Info

Publication number: US2221811A
Application number: US190781A
Authority: US
Inventors: Thomas E Nicklas
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-02-16
Filing date: 1938-02-16
Publication date: 1940-11-19
Anticipated expiration: 1957-11-19

Description

Nov. 19, 1940. T; E. NICKLAS 2,221,811

METHODOF AND APPARATUS FOR CLEANING AND PICKLING METAL Filed Feb. 16, 1958 INVENTOR.

BY mwgg ATTORNEYfi @aientefi New. 3%, 394% ING PIS 5.1

G JKETAL Thomas E. Nicklas, Bay Village, Ohio Application February 16, 1938, Serial No. 190,7831.

6 Claims.

The present invention relates to a novel method and apparatus for pickling metal in the form of a. strip, wire or the like. It is generally the purpose of a pickling operation to subject the surface of a metal to the solvent action of a chemical solution whereby oxides, dirt, sand, and other foreign substances are removed in order to render the surface of the metal in a physically and chemically clean condition. Such a pickling 10' operation, accordingly, comprises in eifect combined washing and chemical actions. Bubbles of hydrogen gas are usually liberated as a result of the chemical action, and tend to adhere to the metal surface, thus impeding further chemical 1'5 section as well as producing an uneven pickling eifect, and in the case of steel, an embrittlement of the ,metal due to the action of nascent hydrogen, X

The general object and nature of my invention, therefore, and in order to enhance and improve the metal pickling operation, is to provide a method and apparatus for rapidly moving the metal in strip or wire form through the pickling bath so that the gaseous products of chemical reaction are immediately and promptly removed from the surface of the metal immediately upon formation, and the washing and cleaning action of the pickling bath upon the metal is greatly increased. Briefly outlined, my invention provides a means and method for coiling and uncoiling metal in strip, wire, or like form, and by means of a power drive, so that it is caused to be drawn through the pickling bath in straight line or linear form.

To theaccomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims, the annexed drawing and the following description setting forth in detail certain means and one mode of carrying out the invention, such disclosed means and mode illustrating, however, but one of various ways in which the principle of the invention may be used. I

In said annexed drawing: 7

Fig. 1 is an elevational view in section, illustrating an apparatus embodying the principle of my invention; and Fig. 2 is a top plan view of Fig. 1.

50 Now refen'ing more particularly to the drawing, there is shown therein a pickling bath tank housing I having the lining of an acid, alkali, or corrosion resistance material 2. A pair of vertical shafts 3 extend through the bottom of the z tank I and are sealed with respect thereto by means of the stumng boxes or packing glands d. The shafts 3 are journalled in the

thrust bearings

5 and 8 carried by the supporting housings i. The lower ends of the shafts igare in turn again sealed with respect to the housings i .by means of the packing glands d." Bevelied gears 8 and I9 connect the lower end of the shafts 3 to the reversible electric drive motors l l.

The upper ends I2 of the shafts 3 are in the form of fiat or squared ends whereby they make a separable driving connection with suitable re= cesses in the bottoms of the drums G3. The drums I3 have a spindle portion i i adapted to receive the metal to be pickled in strip or wire form, such as the coil of metal strip Id. The ends of the metal strip I5 are removably connected to the spindles Id in any suitable manner, such as by means of a hooked or rebent end I'I passing through the axially extending slot It.

Eye bolts I? project from the end of the spindles I4 and .re adapted to be engaged by the hooks I9 car.-ed by the lifting plate 20.

The operation of the above described apparatus is as followsThe drums I3 with their spindles I4 are initially removed from the pickling tank I and the coil of metal, strip I5 is then placed upon one of the spindles and its free end connected to the other, substantially as indicated in Fig. 2. The drums I3 are then lowered by means of the lifting plate into the pickling tank I whereupon they enter into driving connection with the upper ends of the shafts 3. The hooks I9 are then disengaged from the eye bolts I8 and the drums I3 rotated by means of the drive motors I I so as to wind the coil I5 from one drum to the other. The drums are rotated at such a speed as to obtain a linear velocity of the strip I5 through the pickling bath sufficient to accomplish the clearing of the hydrogen bubbles and prevent any surface accumulations. Suitable speeds for the purpose may be from 10 to 100 feet per minute, but obviously the invention is not limited tospecific speeds. This last operation may be repeated or reversed by reversing of the drive motors and recoiling the strip I5 back upon the drum upon which it was originally placed. The strength of the pickling solution, the nature of the particular metal to be pickled, and the degree of pickling desired will determine the number of times that the metal strip I 5 is to be passed through the pickling solution, or coiled and recoiled, on the respective drums. As soon as bubbles of gas such as hydrogenare formed upon the surface of the strip, the linear velocity of the latter together with the frictional resistance of its passage through the solution will be sufiicient to immediately dislodge and remove such gas bubbles. The friction fiuidresistance upon the surface of the metal strip also aids in the mechanically washing and cleaning action of the solution.

It is apparent from the drawing that the outside portion of the coil, where the radius is relatively large, starts on the empty opposite spindle M of much smaller diameter. In other words the part of the coil which is towards the outside and hence curved on a large radius on one spindle is more sharply curved when transferred to the other, while the former inner part of the coil is wound on a larger radius. The radius of bend applied to the metal in the middle of the coil does not change much by this treatment, but none of the coil escapes a bend on a radius of substantially half the outside radius, and every portion of the coil (except the holding tags) is successively straightened and rebent in the bath. The change of curvature so caused will obviously tend to crack off flakes of scale which have been loosened by the pickling bath.

A strong local washing action to carry loosened scale away occurs at the line of tangency where the straight portion of the strip is coming on the coil, along which line (shown as point A in Fig. 2) the liquid is squeezed out by the pinching action between face B and face C.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the means and the steps herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

I therefore particularly point out and distinctly claim as my invention---- 1. A method of cleaning and pickling metal in coiled form comprising the steps of immersing such coil in a pickling bath, uncoiling and then recoiling it while immersed therein and at a linear velocity sufficient to dislodge gaseous particles forming on the surface thereof.

2'. A method of cleaning and pickling metal in coiled form comprising the steps of immersing such coil in a pickling bath, uncoiling and then recoiling it while immersed therein and at a linear velocity sufficient to dislodge gaseous particles forming on the surface thereof, and repeating such uncoiling and recoiling operation until the pickling action is complete.

3. In an apparatus for cleaning and pickling metal, the combination of a pickling bath container, rotatable means in said container for coiling and uncoiling a coil of metal, power driving means located exteriorly of said container and a driving connection between said power means and said rotatable means.

4. In an apparatus for cleaning and pickling metal, the combination of a pickling bath container, a pair of rotatable drums so arranged in said container as to receive a coil of metal mounted on one of said drums and connected for recoiling on the other of said drums, power driving means located exteriorly of said container,

and drive shafts connecting said drums to said power driving means.

5. In an apparatus for cleaning and pickling metal, the combination of a pickling bath container, a pair of rotatable drums so arranged in said container as to receive a coil of metal mounted on one of said drums and connected for recoiling on the other of said drums, power driving means located exteriorly of said container, drive shafts connecting said drums to said power driving means, and a separable connection between said shafts and said drums.

6. In an apparatus for cleaning and pickling metal, the combination of a pickling bath container, rotatable means in said container for coiling and uncoiling a coil of metal, and power driving means for said rotatable means.

THOMAS E. NICKLAS.