US2691819A

US2691819A - Coiling silicon steel strip

Info

Publication number: US2691819A
Application number: US220247A
Authority: US
Inventors: John M Felton; Clarence H Verwohlt
Original assignee: Wheeling Steel Corp
Current assignee: Wheeling Steel Corp
Priority date: 1951-04-10
Filing date: 1951-04-10
Publication date: 1954-10-19
Anticipated expiration: 1971-10-19

Description

Oct. 19, 1954 FELTON ETAL 2,691,819

COILING SILICON STEEL STRIP Filed April 10; 1951 2 Sheets-Sheet 1 INVENTORS Oct. 19, 1954 Filed April 10 1951 J. M. FELTON ETAL COILING SILICON STEEL STRIP 2 Sheets-Sheet 2 INVENTORS Patented Oct. 19, 1954 2,691,819 COILING SILICON STEEL STRIP John M. Felton, Wellsburg,

W. Va., and Clarence H. V'erwohlt, St. Clairsville, Ohio, assignors to Wheeling Steel Corporation, Wheeling, W. Va.,

a corporation of Delawar Application April 10, 1951, Serial No. 220,247

5 Claims. 1

This invention relates to coiling stiff strip. It has to do with controlling stifi strip as it passes to the reel upon which it is being coiled whereby to insure the formation of a straight, even coil. The invention further relates to the coiling of strip which is subject to tearing under heavy tension and to the treatment of such strip as it is being coiled to render it less subject to tearing.

While our invention is of broad utility it has especial usefulness in the coiling of silicon steel strip and particularly in the forming of strip out of stiff sheets or sheets of material subject to tearing under heavy tension such as sheets of silicon steel and coiling the strip thus produced. For purposes of explanation and illustration the invention will be described in connection with the forming of strip out of silicon steel sheets and the coiling of such strip.

Silicon steel in sheet or strip form is very stiff and subject to tearing under heavy tension. Because of its stiffness it cannot be coiled in the conventional way. The strip does not form uniformly into a coil but tends to weave back and forth in the direction of the axis of the coil, forming an uneven and commercially unsatisfactory coil. Various proposals of special ways to coil silicon steel strip have been made but none has been fully satisfactory. We have found the solution to the problem.

We coil silicon steel or other'stifi strip by feeding the strip to a reel, rotating the reel to coil the strip and during such rotation of the reel engaging the strip and pulling backwardly thereon whereby the strip is coiled under heavy tension, insuring formation of a straight, even coil. While we prefer to coil the strip continuously we may when required rotate the reel intermittently to periodically coil portions of the strip and during each period during which the reel is being rotated engage the strip and pull backwardly thereon and during each period during which the reel is not being rotated maintain the strip leading to the reel under heavy tension so that the strip is maintained at all times under heavy tension.

As indicated above, our invention has especial usefulness in the forming of strip out of stiff sheets and coiling the strip. We preferably successively bond stiff sheets end-to-end to form strip and lead the strip to a reel, rotate the reel to coil the strip and during such rotation of the reel engage the strip and pull backwardly thereon whereby the strip is coiled under heavy tension.

Also, we coil strip subject to tearing under heavy tension by coiling the strip under heavy 2 tension and as the strip passes to the coil subjecting it to a stress-relieving heat treatment to render it less subject to tearing.

In a preferred procedure we coil stifi strip subject to tearing under heavy tension by feeding the strip to a reel, rotating the reel to coil the strip, during such rotation of the reel engaging the strip at a tensioning station and pulling backwardly thereon, whereby the strip is coiled under heavy tension, and at the tensioning station subjecting the strip to a stress-relieving heat treatment to render it less subject to tearing. We may form strip out of sheets of stifi material subject to tearing under heavy tension and coil the strip by successively bonding end-to-end sheets of such material to form strip, leading the strip to a reel, rotating the reel to coil the strip, during such rotation of the reel engaging the strip at a tensioning station and pulling backwardly thereon, whereby the strip is coiled under heavy tension, and at the tensioning station subjecting the strip to a stress-relieving heat treatment to render it less subject to tearing.

We further provide apparatus for coiling still strip comprising a reel, means for rotating the reel to coil the strip and means engaging the strip and pulling backwardly thereon as the strip moves to the reel, whereby the strip is coiled under heavy tension, insuring formation of a straight, even coil. We may employ roll means having a sufiiciently large area of contact with the strip as the stripmoves to the reel to enable the roll means to exert a strong frictional drag on the strip together with means tending to turn at least part of the roll means in such a direc tion as to draw the strip away from the reel whereby the strip is coiled under heavy tension. The roll means preferably comprises a tensioning roll about which the strip passes as it moves to the reel and a source of power is preferably connected with the tensioning roll tending to turn that roll in a direction to draw the strip away from the reel but permitting the tensioning roll to turn in the opposite direction due to the frictional pull exerted thereon by the strip as it is drawn by the reel.

We desirably provide means for holding in fixed position both the reel and the tensioning means to maintain the strip under tension when the reel is not rotating. We preferably provide two motors, one for rotating the reel to coil the strip and the other for operating the tensioning means in a direction to draw the strip away from the reel, and we desirably provide brakes by the strip is coiled under heavy tension,

from the bonding station for both the reel and the tensioning means to maintain the strip under tension at all times.

We further provide apparatus for coiling strip subject to tearing under heavy tension comprising a reel, means for rotating the reel to coil the strip, means for maintaining the strip under heavy tensionwvhileit-is being coiled-and means subjecting the strip as it passes to'the reel to a stressrelieving heat treatment to render it less subject to tearing. When we provide means engaging the strip and pulling baclrwardly thereon .as the strip moves to the reel to coil the strip under heavy tension we desirably employ meansin the region of the last mentioned means-heating the strip to subject the strip toxa stress-relieving heat treatment. A heated roll is found to serve the purpose very satisfactorily.

We also provide apparatus for-forming strip out of stiff sheets and coiling the strip comprising bonding means ior:suecessively bonding stifi sheets end-to-end to form strip, a reel positioned to receive the strip directlyfrorn the'bonding means, means for rotating the reel to coilthe strip and means engaging the stripand pulling .backwardly thereonas the strip moves to the reel,

whereby the strip is coiled under heavy tension. When strip is to be formed out of sheets of stiff material subject to tearing under heavy tension we preferably employ bonding means forsucces- .sively bonding suchsheets end-to-end to form strip together withareel positioned to receive the strip directly .from the bonding means, means for rotating the reel to coil the strip,

means engaging the strip and pulling backwardly thereon as the strip-moves to the-reel, whereand means subjecting the strip-as it,passes-to the reel to a stress-relieving heat treatment to render it less subject to tearing.

Other details, objects and advantages of the invention will become apparent as the following description of a present preferred embodiment thereof and a present. preferred method ofpracticing the same proceeds.

In the accompanying drawings we have shown a present preferred embodiment of'the invention and illustrated a presentpreferredmethod of practicing the same, in which Figure 1 is. anelevational view, partly. in cross section, of apparatus for forming strip gout-of sheets and coiling the strip; and

Figure 2 is a plan view of the. apparatus shown in Figure 1.

Referring more particularly to the drawings. there is shown at 2 a bonding or welding station --where sheets are weldedor otherwise bonded successively end-to-end to form strip. The-sheets are advanced from the left .toward .theright, the leading end of each sheetbeing bondedto the trailing end of the precedingsheetsc that a strip made up of sheets bonded together endto-end is formed which is delivered to the right The sheets are clamped in position for bonding by clamping means designated generally by-reference numer- -al 3, the details of which do not'constitute the present invention. The clamping means is claimed in our copendingapplication Serial 'No.

220,246, filed April L10, 1951. There is shown :atraveling welder: head: t which. may; be ofrcon- .ventional construction and nvhich travels ralong :the joint between the contiguousedgespoi gthe clamped. sheets to-welda the edges together. .For

-.purposes of explanation .and illustration the :sheets willbe considered as being jsilicon .steel sheets so that the strip which moves toward the right from the bonding station 2 is silicon steel strip made up of sheets welded together. That strip is stiff so that it cannot be conventionally coiled and it is also subject to tearing under heavy tension. Special provision, therefore, has to be made forcoiling. the -.str ip-.-and since heavy tension must be employed in coiling ,provision must also be made for rendering the strip less subject to tearing.

The strip moves to the right from the bonding station through a drag Wiper 5, about a pair of cooperating rubber covered bridle rolls 6, over a steel idler roll l and to a reel 8 where the strip is formed into acoil by turning of the reel. The reel; 3 is driven by an electric motor 9 through a .gear reduction-unit Ill and a coupling H. The

.6 isan idlerbut the lowerwroll-S iswconnected through a jack shaft-l3 with. an electricimotor 1. 5 which when energized tends to turn the lower roll t in the clockwise direction viewing Figure l, i. e., in such a direction .aszto tendtoi draw-the strip, designated by reference-numeral.- i-E, backwardly or toward the. leftawayiromthe: reel 8, whereby to apply heavy tension to the. strip,.incuring formation on the reel-.8 of astaright even coil. The lower T011116 .hasI-a sufiiciently {large area ofcontact with the-strip to enable-the roll to exert a strong frictionaldrag ontheistrip, the upper roll 6 insuring maintenancepf the strip in proper relation to the2lower1roll=6 to accomplishthe result. Normally thevmotorii does not actually turn the-lower roll =6 in the clockwise direction; on the -contrary,,despite.-the tendency of the motorl-i to turnthelower. roll .5 in the clockwise direction that roll actually turns in the countereclockwise direction due Y to the. frictional: pull exerted thereon by thejstrip=as it is drawn by the reel. liowevergthe-motorrl-l does insure maintaining the-stripxunder heavy tension at all times. The torqueeexerted oni the reel shaft bythe motor-8 and its connections is ing. ia-brakeridis applied-t0.theshaftcofithe lower:v rolls-B and. becomes zeiiectivewhenr the; mo-

tor til is deenergized.

When rotation of the reel 58 -.is .tobe -stopped the -motor d may 'be; deenergizedl to .1 suchi a slegree that the motorwillstand in. aistalledacondition thusinaintaining.tensiorronz the strip continuously. The result. is that. theirelat-ively sstifi strip is maintained 1 under Yheavy': tension .and a straight, even -:coil is .formed. ,on :the reel.

The strip in addition to being stiff may a-lso,

5 as above 'indicatednbe Subject ztotea-ringi under heavy; tension. This is true. ofsilicon steel; strip.

We find it importantto: make provision: for prenxlcring .the :strip ,less subject to tearing. {To thatzend ave subjectthestripns. it passestovthe reel to a stress+relieving-, heatztreatment. While this may. lie-done in various .ways. we. find.-it.de-

sirable to heat ,one.of-the rolls contaetmith which the strip passesfat thetensioning station. .For example, .thesteel idler roll I maybeheated as by electric heating elements disposed therewithin. The heat is transmitted through the surface of the roll to the strip. There is ample opportunity for the heat to penetrate the strip since the strip moves very slowly. The roll is heated to such a temperature that the strip as it passes over the roll will be given a low tem-. perature stress-relieving anneal. The annealing temperature may be of the order of three or four hundred degrees Fahrenheit. This low temperature stress-relieving anneal renders the strip less subject to tearing so that it is not torn even under the heavy tension applied to it.

While we have shown and described a present preferred embodiment of the invention .and a present preferred method of practicing the same it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.

We claim:

1. A method of forming a strip out of sheets of silicon steel comprising turning a partially formed coil of strip of previously bonded together sheets of silicon steel tocontinue formation of the coil, successively bonding additional sheets of silicon steel to the trailing end of the strip, While turning the coil exerting back tension on the strip between the trailing end of the strip and the coil and by said back tension alone causing the strip to form a straight, even coil.

2. A method of forming a strip out of sheets of silicon steel comprising intermittently turning a partially formed coil of strip of previously bonded together sheets of silicon steel to continue formation of the coil, successively bonding additional sheets of silicon steel to the trailing end of the strip, exerting on the coil (even when the coil is not being turned) a coiling force and exerting on the strip between the trailing end of the strip and the coil a force tending to inhibit coiling of the strip and by said forces alone causing the strip to form .a straight, even coil.

3. A method of forming a strip out of sheets of silicon steel comprising intermittently turning a partially formed coil of strip of previously bonded together sheets of silicon steel to continue formation of the coil, successively bonding additional sheets of silicon steel to the trailing end of the strip, exerting on the coil (even when the coil is not being turned) a coiling force, when 0 Number the coil is being turned exerting on the strip between the trailing end of the strip and the coil a force acting on the strip in the direction opposite the direction of the coiling force, by said forces alone causing the strip to form a straight, even coil and when the coil is not being turned braking the strip between the trailing end of the strip and the coil to maintain the coil tight.

4. A method of forming a strip out of sheets of silicon steel comprising turning a partially formed coil of strip of previously bonded together sheets of silicon steel to continue formation of the coil, While turning the coil exerting on the strip between the trailing end of the strip and the coil a force tending to move the strip in the reverse direction and between the trailing end of the strip and the coil subjecting the strip to a stress-relieving heat treatment whereby to insure the formation of a straight, even coil.

5. A method of forming a strip out of sheets of silicon steel comprising turning a partially formed coil of strip of previously bonded together sheets of silicon steel to continue formation of the coil, while turning the coil exerting on the strip between the trailing end of the strip and the coil a force tending to move the strip in the reverse direction, between the trailing end of the strip and the coil subjecting the strip to a stressrelieving heat treatment and by said force alone causing the strip to form a straight, even coil.

References Cited in the file of this patent UNITED STATES PATENTS Name Date Roberts Mar. 16, 1909 James Apr. 23, 1918 Baily Apr. 12, 1927 Shoultz Aug. 15, 1933 Fowler Oct. 23, 1934 Hudson Sept. 22, 1936 Hanson Nov. 3, 1936 Younts Feb. 16, 1937 Asbury et al. May 30, Ashworth Apr. 2, Webster May 21, Eitzen Aug. 26, 1941 Cook May 18, 1943 Paris et a1. Apr. 23, 1946 Morton Sept. 4, 1951