US3354723A

US3354723A - Molten metal sampler

Info

Publication number: US3354723A
Application number: US446939A
Authority: US
Inventors: William F Smith
Original assignee: Jones and Laughlin Steel Corp
Current assignee: Jones and Laughlin Steel Corp
Priority date: 1965-04-09
Filing date: 1965-04-09
Publication date: 1967-11-28
Anticipated expiration: 1984-11-28

Description

NOV. 28, 1967 5M|TH 3,354,723

MOLTEN METAL SAMPLER Filed April 9, 1965 INVENTOR. WILLIAM F. SMITH his ATTORNEY United States Patent 3,354,723 MOLTEN METAL SAMPLER William F. Smith, Aliquippa, Pa., assignor to Jones &

Laughlin Steel Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Filed Apr. 9, 1965, Ser. No. 446,939 6 Claims. (Cl. 73425.6)

This invention relates to apparatus for obtaining a sample of metal for analytical purposes from a molten bath. It is more particularly concerned with apparatus for obtaining a sound rod-like sample of such metal.

My invention is particularly adapted for use in the manufacture of steel and will be described in that connection hereinafter. It is, however, suitable for other metals as well.

In the manufacture of steel it is necessary to determine the content of carbon and often of other constituents of the melt while it is in the molten state. This requires sampling of the melt. It is conventional to suck molten steel up into a glass tube of a small uniform cross section bore so that it solidifies in the tube which is then broken away from the sample so obtained. If a sound sample can be obtained, that is, one free from internal cavities, then a length of sample corresponding to a predetermined sample weight can be obtained by cutting a section of the rod in an appropriate jig. Unfortunately, although the molten steel from which the sample is sucked is usually deoxidized so that there is no evolution of gas therefrom, the steel sucked up into the glass tube in the conventional way tends to solidify against the wall of the tube but to remain molten in the center. The molten steel then runs back down, leaving a cavity.

It is the principal object of my invention to provide apparatus adapted to sucking molten metal into a tube of uniform cross section so as to produce a sound sample. It is another object to provide such apparatus with easily connectable sample tubes and easily replaceable elements. Other objects of my invention will appear from the following description thereof. I provide my suction device with a chill element in the sample tube dimensioned and positioned to bring about rapid solidification of the molten metal throughout its cross section adjacent the chill, and progressive solidification of the metal therebelow at a rate sutlicient to prevent the running out of metal from the center of the sample. Three embodiments of my invention presently preferred by me are illustrated in the attached figures, to which reference is now made.

FIGURES 1, 2, and 3 are elevations in section of first, second and third preferred embodiments of my invention, respectively.

In the figures and the description which follows, elements which are common to the various embodiments of my invention are identified by like reference characters. The apparatus as illustrated in FIGURE 1 comprises a conventional glass sample tube 1 of uniform bore which is connected to a suction tube 4 by a sleeve 3 so as to leave a gap or space of enlarged diameter 7 between the facing ends of the two tubes. Sleeve 3 is of rubber or like stretchable material which grasps sample tube 1 and suction tube 4 tightly, but permits those tubes to be readily disconnected therefrom and replaced. The end of suction tube 4 remote from sleeve 3 is fitted to a bulb 5 of rubber or other collapsible resilient material. Within the bore of 3,354,723 Patented Nov. 28, 1967 "ice sample tube 1 is positioned chill element 2 which is of slightly smaller diameter than the bore of sample tube 1. Chill element 2 is formed with a projecting flanged end 6 which is disposed in the gap 7 previously mentioned.

In the embodiment of my apparatus illustrated in FIG- URE 2, sample tube 11 is formed with constricted boreportions 13 and 14 spaced from each other, and chill element 12, which is cylindrical in shape and of uniform cross section smaller than the bore of sample tube 14, is positioned between its constricted portions so that it cannot pass beyond either of them. The apparatus is otherwise the same as that illustrated in FIGURE 1.

In the embodiment of my apparatus illustrated in FIG- URE 3, the sample tube 21 is fitted with a constricted bore portion 23 spaced from its end which is within sleeve 3. Chill 22 is of uniform cross section smaller than the bore of sample tube 21 and is positioned between constricted bore portion 23 and suction tube 24. End portion 25 of chill 22, which extends into sleeve 3, is of smaller cross section than the body of the chill, so as to minimize the heat transferred to sleeve 3. The bore 28 of suction tube 24 is smaller than the diameter of chill 22 or, alternatively, is off center, so that chill 22 cannot enter it. It is not necessary, of course, that suction tube 24 be of this construction throughout its length. Only its end portion within sleeve 3 need be so formed, the apparatus is otherwise the same as that of the embodiment of my FIG- URE 1.

The operation of my apparatus will be described with reference to the empodiment of FIGURE 1. The operator holds the device by bulb 5, compresses that bulb to drive the air out of it through suction tube 4, sleeve 3, and sample tube 1, then immerses the open end of sample tube 1 below the surface of the molten steel. He releases the pressure on bulb 5 so creating a suction. Atmospheric pressure on the surface of the molten metal causes metal to enter sample tube 1 and rise until it encounters chill element 2 which effects immediate solidification of the molten metal in contact with it. Chill 2 is kept in place by flange 6 which cannot move out of the larger bore gap area 7. When the metal has solidified in sample tube 1, the latter is disconnected from sleeve 3 and broken, which releases the rod-like sample. A predetermined length of this sample is then cut and used for analytical determinations. The chill element 2 is recoverable and can be used again with other detachable sample tubes 1.

The operation of the embodiments of my invention illustrated in FIGURES 2 and 3 is the same as that of FIG- URE 1 above-described.

Chill elements

2, 12, and 22 are conveniently made of copper or other metal of high conductivity. Suction may be provided by means other than the bulb 5, for example, a suction pump, or an evacuated container.

I claim:

1. Apparatus for obtaining a sound rodlike sample of metal from a molten bath thereof comprising suction means, a tube of uniform bore detachably connected at one end to the suction means, a chill element in the tube, the chill element cross section being less than that of the bore so that suction produced by the suction means draws molten metal into the tube when its open end is immersed therein, the chill element cross section and length being sufficient to cause molten metal drawn into the tube to solidify against the chill, and means for positioning the chill element intermediate the open end of the tube and the suctions means.

2. Apparatus of claim 1 in which the chill positioning means comprises a localized tube section of enlarged bore and a flange on. one end of the chill element fitting within the enlarged bore, but wider than the uniform bore.

3. Apparatus of claim 2 in which the tube section of enlarged bore is an external sleeve detachably connecting the tube and the suction means.

4. Apparatus of claim 1 in which the chill positioning means comprise spaced apart bore constrictions between which the chill element is confined.

5. Apparatus of claim 4 in which one constriction comprises the end of the suction means detachably connected 15 to the tube of uniform bore.

6. Apparatus of claim 1 in which the chill positioning means comprise a bore constriction and a localized tube section having a bore eccentric with respect to the tube of uniform bore between which the chill element is con- 5 fined.

References Cited UNITED STATES PATENTS 2,970,350 2/1961 Feichtinger. 10 3,221,559 12/1965 Miller et al. 73425.4

3,309,928 3/1967 Cavalier 73-4256 LOUIS R. PRINCE, Primary Examiner.

DANIEL M. YASICH, Assistant Examiner.

Claims

1. APPARATUS FOR OBTAINING A SOUND ROD-LIKE SAMPLE OF METAL FROM A MOLTEN BATH THEREOF COMPRISING SUCTION MEANS, A TUBE OF UNIFORM BORE DETACHABLY CONNECTED AT ONE END TO THE SUCTION MEANS, A CHILL ELEMENT IN THE TUBE, THE CHILL ELEMENT CROSS SECTION BEING LESS THAN THAT OF THE BORE SO THAT SUCTION PRODUCED BY THE SUCTION MEANS DRAWS MOLTEN METAL INTO THE TUBE WHEN ITS OPEN END IS IMMERSED THEREIN, THE CHILL ELEMENT CROSS SECTION AND LENGTH BEING SUFFICIENT TO CAUSE MOLTEN METAL DRAWN INTO THE TUBE TO SOLIDIFY AGAINST THE CHILL, AND MEANS FOR POSITIONING THE CHILL ELEMENT INTERMEDIATE THE OPEN END OF THE TUBE AND THE SUCTIONS MEANS.