US2182060A - Apparatus for treating strip steel - Google Patents

Description

' Dec. 5, 1939. A. SIMON APPARATUS FOR TREATING STRIP STEEL File d June 18,v 1937 2 Sheets-Sheet 2 3 3 v q m lli UL F H FU.-.::1J.:

INVENTOR A420 5/010 TTORNEY Patented Bees, 1939 APPARATUS FOR TREATING STRIP STEEL Aaron Simon, Brooklyn, N. Y., assignor to Tri-' angle Mechanical Laboratories Cor-1).,

York, N. Y., a corporation of New York Application June 18, 1937, Serial No. 148,874

1 Claim. (01. 2 6-3) This invention relates generally to a means for treating strip steel.

Que of the objects of this invention is to provide an apparatus for treating strip steel of the type, for example, suitable for use in m g razor blades and the like, ir. which the strip steel is heat treated so as to produce thereon a thin finish coating in the nature of a blue oxide film, the construction of the apparatus being such that the strip steel will be prevented from scaling, thus insuring uniformity and evenness of the blue finish.

Another object of this invention is to provide in combination with an apparatus of the character described for heat treating strip steel, an improved construction of chill means.

Still another object of this invention is to proe vide an apparatus of the character described for treating strip steel, which shall comprise relatively few and simple parts, which shall be inexpensive to operate, which shall be easy to assemble and maintain, and which at the same time shall operate with a high degree of ,eihciency.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the fea-.

tures of construction, combinations of elements, and arrangement of parts which will be exemplifled in the construction hereinafter described,.

80 and of which the scope of application will be indicated in the claim.

Inthe accompanying drawings, in which is shown one of the various possible embodiments of this invention,

3 Fig. 1 is a diagrammatic view illustrating the continuous process'of treating strip steel embodying this invention;

Fig. 2 is an enlarged horizontal section of a portion of the apparatus illustrated in Fig. 1;

Fig. 3 isan enlarged vertical section of a portion of the apparatus illustrated in Fig. 1;

Fig. 4 is an enlarged cross-sectional view taken substantially on the, line 4-4 of Fig. 3;

Fig. 5 is an enlarged cross-sectional view taken substantially on the line 5-5 of Fig-3;

Fig. 6 is an enlarged cross-sectional view-taken substantially on the line 6-4 of Fig. 3

Fig. 7 is a cross-sectional view taken s tially on the line |-l of Fig. 3; and

5 Fig. 8 is an enlarged cross-sectional view taken substantially on the line 8-8'0f Fig. '1.

Referring now in detail to the drawings, there will be described an improved process and apparatus for treating strip steel of the type suitable tan for use as razor blades, but it is understood that stand ii,

this invention may be satisfactorily practiced in connection with the treatment of steel suitable for other uses. n I

Referring'particularly to Fig. 1 of the drawings, there is disclosed a diagrammatic arrangement 5 of an apparatus for treating a supply of strip steel to produce a blue coatingthereon. The supply of strip steel ill, from a roll R, supported on a is fed through a muflle i2, passing through a furnace perature above the lower critical point and then quickly quenched by means, of a pair of chili blocks l5, to harden the same. It is then led through a pair of tension rollers i6 and through "a tempering furnace ll, again cooled and led on 15 through a second pair of tension rollers l8 to'be wound up on a reel IS. The said reel L9 may be driven by any suitable driving mechanism, such as a motor 20.

The type of furnace i4 employed may be of the. electrical type, as shown in Figs. 2 and 3, and comprising a top wall 2|, a bottom wall 22, side walls 23, and end walls 24 and 25. Centrally disposed of the furnace is a longitudinal opening in which there is positioned a muffle l2, said muiile being of suitable material and preferably made in the formof a flattened seamless tube open at both ends, as shown in Fig. 4. Surrounding a portion of themuille l2 within the furnace i4 is a heating coil preferably of one piece of suitable material and arranged in a series of con volutions spaced "from and adapted to encasethe top, bottom and one side of the muflle l2, as shown in Fig. 5. The spaces within the furnace between-the opening 25 and the top and bottom walls 2i and 22 are filled with suitable heat insulating material such as fire brick. It is noted that the ends i211 and no of the-muffle I2 project outwardly beyond the end walls 24 and 25 fora predetermined distance.

The heating coil 30 may be connected to any source of electrical supply by suitable conductor means (not shown). As the strip steel [0 is led through the muflle l2, it is heated to a temperature below the critical temperature in an atmosphere of such character that a thin uniform blue 'oxide coating is formed on the surface of the 14, where itisheated to a teml0 are supported on a bracket 38 which is'flxed to the may be introduced into the muflle l2 from a source of supply, such as a tank 3|, through a hose connection 32 connected ,at the free end thereof to a specially designed nozzle member as it enters the muiiie, and at the same time, to Y increase the pressure thereof. The member. 33 is provided with a drain or outlet pipe 34 designed to drain off the condensation or excess steam in the member 33. The member 33 may be slidably supported on a bracket 35 which is fixed to the wall 24 of the furnace l4 and which may be slidably moved by means of a clamp 38 to adjust the distance which the end 33a projects inside the muflle I2.

It is well known that when steel heated to te peratures as high as the lower critical temperature thereof is exposed to the atmosphere, there immediately forms upon the steel a flaky, nonadherent oxide coating, commonly called scale".

It is noted that the end 12b of the muflle l2 extends beyond the wall 25' of the furnace l4 for a slight distance. A pair of chill blocks 31 and 38 wall 26 of the furnace I4. The chill blocks 31 and 38 are symmetrical in construction and comprise head portions 31a and 38a and integral shank portions 31b and 38b. Each of the blocks "and 38 is of hollow construction and is provided with an inlet 40 and an outlet 4| adapted to supply to the interior of the blocks 31 and 38 a continuously flowing stream of cooling fluid, such as water from a source of supply (not shown) The bottom surface 31c of the block 31 and the top surface 38c of the block 38 are adapted to be disposed in contacting relationship and each of said surfaces is provided with a centrally disposed slightly recessed portion 42.. The combined recesses 42 are adapted to be in registry when the blocks 31 and are placed in superimposed re-' s lationship, as shown in the drawings, and to form aguideway for the passage of the strip of steel l0,

which is adapted to pass therethrough upon leaving the furnace I4; In order to prevent the surrounding atmosphere from scaling or otherwise aflfecting the strip of steel III as it leaves the muifle l2 to enter the recessed guideway 42 between the chilling blocks 31 and 38, the head portions 310' and 38a of 'the chili blocks 31 and 38 are each provided with symmetrical recessed areas and 45, which are designed so as to be of the same shape and contour as the outer surface of the "to be received in said recesses and 45, as clearm ufle [2. The end 12b of said muille is adapted recesses 44 and 45 are of predetermined depth so 1 that the outer surfaces of the head portions 31a and 38a of the chill blocks will lie flush up against the wall 25 of the furnace 14 to form a substantially air tight seal surrounding the muilie l2.

It is thus seen from the above-described construction that when the strip It leaves the muille l2, it will immediately enter the recess 42 between the chill blocks to be immediately quenched and hardened before the surrounding atmosphere has been able to act upon said strip to damage the same. As the strip [0 passes through the chill blocks to be cooled, it may then be led between the rollers l6 and into the tempering furnace l1, as previously described.

It is desirable that the recess 42.between the chill blocks be relatively slight so that no air will 4 enter between the blocks to affect the blue coating thereon during the quenching or chilling process. The bottom walls 310 and 38c 01 the chill blocks 31 and38 have, therefore, been constructed so as to be slidably removed'after the recess-42 has been worn away by the friction of th'e.passing of the strip l0 therethrough, in order to replace the walls 31c and 380 with new walls containing the proper amount of recess. walls 310 and 380 may be removably attached to the blocks 31 and 38 by any suitable attaching means, such as screws 45.

The furnace l4 may be provided with a thermostatic heat control device 51! to provide for automatically shutting off of the electric current when the temperature in the space 25 surroundbelow a predetermined amount.

While in the operation of the above-described Thev process and apparatus for treating strip steel a mixture of steam and air was introduced into the muflie to produce a blue oxide coating on the strip, it is understood that in the apparatus constructed in accordance with this invention there may be used other suitable atmospheres, such for example as a proper-mixture of illuminating gas and It will thus be seen that there is provided a device in which the several objects of this inven-' r 40 As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative "and not in a limiting sense.

Having thus described my invention, I claim as new and desire .to secure by Letters Patent:

' In an apparatus for treating a strip'steel' of the character described, a muiiie adapted to have a steel strip led therethrough to be heated to a predetermined degree of temperature, said muflle supply into said muflieat saidprojecting open end, said last named means comprising a flattened tubular nozzle received within said muflie and having a drain outlet disposed outside of said muflle.

AARON SIMON,

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