US3241735A

US3241735A - Method and apparatus for handling metal strip

Info

Publication number: US3241735A
Application number: US315314A
Authority: US
Inventors: Neil J Ranney
Original assignee: Production Machinery Corp
Current assignee: Production Machinery Corp
Priority date: 1963-10-10
Filing date: 1963-10-10
Publication date: 1966-03-22
Anticipated expiration: 1983-03-22

Description

March 22, 1966 J RANNEY I 3,241,735

METHOD AND APPARATUS FOR HANDLING METAL STRIP Filed Oct. 10, 1963 2 Sheets-Sheet 1 FIG.

INVENTOR. NEIL J. RANNEY ATTORNEYS N. J. RANNEY March 22, 1966 METHOD AND APPARATUS FOR HANDLING METAL STRIP Filed Oct. 10, 1963 2 Sheets-Sheet 2 v R 0 W WM a E A Rw M WR \8! m J. T A E N FIG. 4

United States Patent 3,241,735 METHOD AND APPARATUS FOR HANDLING METAL STRIP Neil J. Ranney, Mentor, Ohio, assignor to Production Machinery Corporation, Mentor, Ohio, a corporation of Ohio Filed Oct. 10, 1963, Ser. No. 315,314 11 Claims. (Cl. 226-4) This invention pertains to the art of processing metal strip and more particularly to a method and apparatus for handling metal strip as it passes through a processing line.

The invention is particularly applicable for handling heavy gauge steel strip in a processing line for removing oxide scale from the surfaces of the strip and it will be described with particular reference thereto; however, it will be appreciated that the invention has much broader applications and may be used in various processing lines adapted to handle any gauge of metal strip.

The term metal strip indicates a strip formed from any metallic material such as steel, iron, copper, aluminum, zinc and tin, to name only a few.

The term processing line as used herein includes apparatus which conveys or guides a metal strip, in uncoiled form, around rolls and through various processing steps, such as heating, cooling, cleaning, coating, hot or cold working, etc., apparatus for initially uncoiling the strip and apparatus for subsequent coiling or otherwise handling the strip.

The terms line tension and line speed as used herein refer to the tension and speed of the metal strip as it moves through the processing line.

In processing metal strip, even if the strip has a somewhat heavy gauge, it is the common practice to hot roll the strip into an intermediate size strip having a thickness somewhat close to the desired thickness of the final strip. This hot rolling operation is carried out in the atmosphere; therefore, an oxide scale forms on the surfaces of the hot rolled strip which scale must be removed before the strip can be satisfactorily progressed through additional processing operations, such as cold rolling.

To remove the scale from the surfaces of the strip, it hasheretofore been common practice to uncoil the hot rolled strip and pass the strip through an acid pickling bath after which the strip was again coiled or was immediately conveyed into a subsequent processing line. The use of an acid for removing the scale created obvious disadvantages. For instance, it was necessary to provide elaborate tanks and piping for handling the acid. The disposal of .the acid waste was difficult and expensive because the acid created serious pollution problems when discharged into streams or sewers. If the acid were first neutralized before disposal, expensive equipment and chemicals were required.

To overcome these disadvantages of using acid in the processing of strip, it has heretofore been suggested that the scale could be removed from the strip by a physical abrading process wherein both surfaces of the strip were subjected to a stream of small steel shot propelled against the surfaces by high pressure air or by centrifugal force. Such a scale removing process would overcome the most prevalent disadvantages of acid pickling; however, its

use has been limited by the geometry of the strip as it was .was. impinge dudownwardly against the upper surface of the strip and upwardly against the lower surface of the strip. There was no satisfactory way of removing all of the scale and shot from the upper surface of the strip, and it was mechanically awkward to blast the lower strip surface.

To overcome this disadvantage, it has been suggested that the strip be conveyed upwardly in a substantially vertical direction so that the steel shot impinging against the surfaces of the strip would fall downwardly as the strip was moving upwardly. This arrangement was equally unsatisfactory because the shot and scale tended to drop into the guide rolls adjacent the bottom of the strip where it caused rapid failure of the rolls and marred the surfaces of the strip. In order to blast strip in a vertical pass, the blast wheels must be mounted horizontally, with their axes vertical, and it was found that the grit did not flow properly with the wheels in this position.

Recently, it has been found that superior results can be obtained by conveying the metal strip in a vertical plane, i.e. edgewise, past the shot blasting apparatus. In this manner, the surfaces of the strip face horizontally as the strip moves through the shot blasting apparatus and the residue of the blasting operation drops downwardly away from the strip. To utilize this vertical plane blasting operation, it has been suggested that all of the processing line equipment be redesigned to handle the strip on edge. The existing line equipment could not be used because it was adapted to handle the strip in only a horizontal plane. Such redesign of the line equipment would involve a considerable capital expense and it was not necessary for all operations in processing the strip.

The present invention is directed toward a method and apparatus for handling metal strip which method and apparatus allow the strip to be conveyed edgewise through a shot blasting operation without requiring the redesign of the other equipment to handle strip in the edgewise position.

Although the use of equipment for conveying strip in an edgewise position (which means that the strip is moving in a vertical plane when moving parallel to the rolling mill floor) is discussed with special emphasis on shot blasting, edgewise conveying has other advantages in processing thin metal strip. For instance, when the thin strip is being annealed by passing the strip through a horizontally extending furnace, the furnace must have a substantial length. The long furnace length is dictated by the rapid speed of the strip and the high annealing temperature of the strip. If the strip is traveling in a horizontal pass plane, the strip tends to sag in the long furnace. Intermediate support rolls within the furnace have not been very satisfactory because they could not withstand the high furnace temperatures and they tended to mar the surfaces of the heated strip.

To overcome these disadvantages, the furnace could be provided with a substantial vertical height so that the sag, or catenary, could be accommodated within the furnace without support rolls. This of course was very expensive and required substantial space. Another solution to the problem was to decrease the catenary by increasing the tension of the strip. This often resulted in stretching of the strip, especially when it was relatively thin and was heated to a very high temperature. Since these two solutions had obvious disadvantages, it was suggested that the thin strip could be conveyed in a vertical direction through a vertically extending furnace. This arrangement was not completely satisfactory because an upper roll was required in the furnace which roll could mar the surface of the strip. Even with the upper roll, the necessary furnace length would require a considerably higher structure than possible in some rolling mill-s. Also, the weight of the strip would tend to stretch the heated strip as it was moving through the furnace.

.spect to the previous pass plane.

All of these disadvantages can be overcome by conveying the thin strip through the furnace in an edgewise position since the rigidity of the strip itself will limit the catenary. A few bottom support-s constructed of heat resistant material which is not susceptible'to deterioration can furnish the necessary vertical support of the strip without the disadvantage of guide rolls.

It is obvious that other processing operations may be more satisfactorily performed with the strip in an edgewise, or vertical pass plane.

In accordance with the present invention there is provided a method of changing the pass plane of a metal strip moving through a processing line from a first plane to a second plane comprising the steps of guiding a first section of the strip along the first plane, driving the first section at a predetermined line speed and under line tension, guiding a second and subsequent section of the strip along the second plane, driving the second section at a predetermined line speed and under line tension, forming a low tension, natural loop in the strip between the first and second sections the strip being twisted in the loop between a substantially horizontal and a substantially vertical disposition, and correlating the speeds of the sections to maintain the natural loop.

In accordance with another aspect of the present invention, there is provided an apparatus for changing the pass plane of a metal strip moving through a processing iine comprising a first and second set of pinch rolls spaced from each other to define an intermediate pass in the processing line, the pinch roll sets being obliquely disposed with respect to each other to define the desired change in the pass plane, means for controlling the relative speed of the pinch rolls to maintain the tension in the intermediate pass substantially below the line tension in the processing line. In this manner, the strip moving through the intermediate pass can form a natural loop which will allow movement between the pinch roll sets without deformation of the strip.

The method and apparatus defined above can be used for changing the pass plane of a metal strip from a horizontal pass plane to a vertical pass plane for moving the strip edgewise through a processing operation which may be more expeditiously performed with the strip on edge. Such an operation is shot blasting of the strip to remove oxide scale.

It will be appreciated that the invention may be used for changing the pass plane of metal strip between various planes and not necessarily between a horizontal and vertical plane. Essentially, the present invention allows a shift in the pass plane of a strip traveling through a processing line so that the new pass plane is oblique with re- The term oblique ndicates that the shift in pass plane is not just a change 1n direction as found when a strip in a horizontal pass plane is shifted around a roll into an upwardly extending pass plane or into another horizontal pass plane parallel with the first plane. Consequently, the invention relates to shifting the pass plane of the metal strip in a variety of combinations with the exception of those changes indtcated above.

The primary object of the present invention is the prov1s1on of a method and apparatus for shifting the pass plane of a metal strip moving through a processing line from a first plane to a second plane oblique to the first plane.

Another object of the present invention is the provision of a method and apparatus for shifting the pass plane of a metal strip moving through a processing line from a first plane to a second plane oblique to the first plane which method and apparatus does not plastically distort the metal strip.

Another object of the present invention is the provision of a method and apparatus for shifting the pass plane of a metal strip moving through a processing line from a first plane to a second plane oblique to the first plane which method and apparatus include the formation and maintenance of a natural, low tension loop between the two planes.

Yet another object of the present invention is the provision of a method and apparatus for shifting the pass plane of ametal strip moving through a processing line from a first plane to a second plane oblique to the first plane wherein the length of the processing line required for the shift in the pass plane is minimized.

Yet a further object of the present invention is the provision of a method and apparatus for shifting the pass plane of a metal strip moving through a processing line from a first plane to a second plane oblique to the first plane which includes the formation and maintenance of a natural, low tension loop between the two planes and wherein the length of all longitudinally extending lines in the strip of the loop are substantially the same.

These and other objects and advantages will become apparent from the following description used to illustrate the preferred embodiment of the present invention as read in connection with the accompanying drawings in which:

FIGURE 1 is a side elevational, schematic view illustrating the preferred embodiment of the present invention wherein the change in pass plane is between horizontal and vertical planes without a change in the direction of movement of the metal strip;

FIGURES 2 and 3 are partial, schematic, views illustrating modifications of the embodiment shown in FIG- URE 1 wherein the strip is shifted from a horizontal to a vertical pass plane with the direction of the strip being reversed; and

FIGURE 4 is a partial, schematic view illustrating a modification of the present invention wherein the pass plane is shifted from horizontal to vertical and the direction of the moving strip is changed int-o approximately a right angle.

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only and not for the purpose of limiting same, FIGURE 1 shows a processing line A for removing oxide scale from metal strip B. The metal strip is directed through the processing line from a coil 10 which is supported onto an appropriate apparatus such as a processing uncoiler (not shown). At the opposite end of the line there is provided a take-up roll 12 which recoils the metal strip -B as it comes from the processing line. It is appreciated that the take-up coil 12 may be replaced by a subsequent processing line so that the strip B can progress from processing line A into a subsequent line for cold rolling, annealing or similar operations. Usually, the coil 10 is mounted on an apparatus which shears the trailing end of the coil and welds the leading end of another coil thereto so that the strip B as it progresses through line A is substantially continuous.

Within the processing line A there are provided a plurality of pinch roll sets 20, 22, 24 and 26 which divide the strip B into (a) pass 30 which is in a horizontal plane i.e. the large flat surfaces face vertically, (b) a first intermediate pass 32 (0) pass 34 which is in a substantially vertical plane, i.e. the large surfaces face horizontally, (d) a second intermediate pass 36, and (e) pass 38 which is in a horizontal plane similar to the plane of pass 30.

The pinch rolls 20, 22 definethe intermediate pass 32 and these rolls are obliquely positioned with respect to each other. This indicates that the nip of each pinch roll set is in a plane not coinciding with the plane of the .other set and not parallel with the other set. Thus, the

distances between corresponding points on the nip of the obliquely arranged pinch roll sets 20, 22 vary. This same general discussion applies to obliquely arranged pinch rol-l sets 24, 26 which define the second intermediate pass 36.

In the pass 30 there is provided a conventional five roll leveler 40 which is adapted to pull the strip B from coil and flex the strip into a flat configuration. The leveler 40 is driven by an appropriatemechanism (not shown) so that the strip B moves through the processing line A at the desired speed and under a desired line tension. In accordance with one embodiment of the present invention, the strip B is 72 inches wide and A inch thick with a force applied of 9,000 pounds in a direction longitudinal of the strip. Consequently, the strip has approximately 500 lbs/in. of tension applied as it is moving through the processing line in horizontal pass 30. It is appreciated that auxiliary guide rolls and drive rolls may be used in the horizontal pass 30 to convey the strip B from coil 10 to pinch roll set 20 under the proper tension and in the proper position. I

The strip B is in a vertical plane pass 34 which vertical plane greatly enhances the characteristics of certain line operations such as, with-out limitation, shot blasting the opposite surfaces of the strip to remove oxide scale which formed while the strip was being hot rolled. Shot blasting unit 50 is schematically represented and includes a plurality of heads 52 which direct, by air or centrifugal force, a myriad of small steel shot against the opposite surfaces of the strip which shot abrades the strip and removes the oxide scale. With the strip in a vertical plane, i.e. edgewise, the shot easily drops from the strip before the strip enters the nip of pinch roll set 24. Although the pass 34 is defined as vertical, it is appreciated that the strip need not be exactly 90 with respect to horizontal and that various lesser degrees of inclination with horizontal would function satisfactorily. Thes-peed of strip B in pass 34 is the same as the speed of strip B in all other portions of the line and a line tension is applied to the strip in this pass.

In the horizontal pass 38, the take-up roll 12 or a subsequent processing operation can be used, as was previously described. Again, the speed of the strip in pass 38 is the same as the speed in other portions of the processing line and the strip is under line tension so that it can be conveniently conveyed to the subsequent operations.

The present invention pertains to a method and apparatus for shifting the pass plane of strip B as it moves through line A and, in accordance with the illustrated embodiment of the present invention, the pass plane is shifted from a horizontal plane in pass 30 to a vertical plane in pass 34. It is appreciated that other oblique shifts in the pass plane of the strip could be made by utilizing the present invention. The shift is accomplished in the first intermediate pass 32 and the apparatus and method for accomplishing the shift will be described in detail. It is to be appreciated that this discussion will apply equally to the apparatus and method for shifting the pass plane of strip B between pass 34 and pass 38, which is not described.

As previously explained, roll sets 20, 22 which define intermediate pass 32, are obliquely positioned with respect to each other. In accordance with the illustrated embodiment of the invention, roll set 20 is driven by a wound rot-or motor 60 having primary power lines 62, 64 .and 66 with a secondary circuit speed control '68 of conventional construction. The output :of motor 60 is physically connected to the roll set 20 by an appropriate mechanism, schematically represented as line 70. By this construction, variations in control 68 changes speed of motor 60 and, thus, the speed of roll set 20.

In a similar manner, wound rotor motor 80 having

primary power lines

82, 84 and 86 and a secondary circuit speed control 88 is coupled by shaft 90 onto the roll set 22. The motors 60, 80 can be adjusted to synchronize the speed of roll sets 20, 22 and also to adjust for any difference in the speeds of the spaced roll sets.

To control the secondary speed controls 68, 88 there is provided a sensing device 100 which, in accordance with the illustrated embodiment of the present invention, is a feeler which is conected to a control 102. Changes in the position of the feeler 100 causes a signal to be generated by control 102 which signal is furnished to motors 60, by control lines 104, 106, respectively. Thus, the position of feeler controls the speed of motors 60, 80.

In operation of the present invention, the strip B is threaded through the processing line A and a natural loop Cis provided in the strip between the pinch roll set 20 and the pinch roll set 22. The term natural loop as used herein indicates that the length of the strip B between roll sets 20, 22 is substantially greater than the spacing between these sets which spacing is represented by a and that the excess in strip length is allowed to take a natural shape which, in practice, has been found to produce a loop wherein no part of the strip is distorted beyond its elastic limit. The speed of roll sets 20, 22 is so synchronized that there is no substantial tension in the natural loop C, except for the tension caused by the weight of the loop itself. The size of the natural loop is determined somewhat by the width and thickness of the material and the material itself; and the loop is sufficiently large to prevent stretching of any portion of the strip as it progresses from pass 30 to pass 34. The term natural loop does not exclude guide rolls to form the path of the loop or to support certain parts of the loop. Primarily, the natural loop must be so formed that stretching and kinking of the strip is prevented;

The size of the natural loop C is maintained, in ac cordance with the illustrated embodiment of the present invention, by the feeler 100. When the feeler senses a decrease in the size of the natural loop C, the linear speed of roll set 20 is increased with respect to the linear speed of roll set 22. This can be accomplished by increasing the speed of motor 60 or decreasing the speed of motor 80 or a combination of these actions. The control 102 adjusts the speed of motors 60, 80 to increase the length of the loop so that the desired size can be maintained. If the feeler senses an increase in the loop over a predetermined maximum, the speed of roll set 22 must be increased with respect to the speed of roll set 20; therefore, the appropriate adjustment of motors 60, 80 is effected by the control 102.

It is appreciated that one of the roll sets 20, 22 may be driven at a constant speed and the other roll set could then be adjusted to increase or decrease the size of the natural loop C without departing from the intended spirit and scope of the present invention. It is also within the scope of the invention to provide various sensing devices such as photoelectric cells, gas jets, proximity switches, etc.

Referring now to FIGURES 2 and 3, there is illustrated a method and apparatus for shifting the pass plane of metal strip B from a horizontal pass 124 to a vertical pass 126 in a manner quite similar to the method and apparatus illustrated in FIGURE 1; however, the vertical pass 126 is reversed in direction from the horizontal pass 124. It is readily seen that the present invention is adapted to change the pass plane of the strip B and also to change the general direction of the strip. Roll sets 120, 122 separate the intermediate pass 128 from horizontal pass 124 and vertical pass 126.

Motors

130, 132 control the roll sets in accordance with a signal from sensing device 134.

The natural loop D of FIGURE 2 and natural loop E of FIGURE 3 are formed'between the roll sets 120, 122 so that there is substantially no tension in these natural loops except for the tension caused by the weight of the strip B. Natural loop D is formed by bringing the lower edge of strip B in pass 124 to the uppermost part of pinch roll set 122. This natural loop diifers from the natural loop E shown in FIGURE 3 wherein the lower edge of strip B in pass 124 is brought to the lowermost edge of pinch roll set 122. It is appreciated that the diiference between these two natural loops is minor and the apparatus operates the same although there may be some advantage in certain instances in bringing a certain edge of the strip to the top of the vertical pass 126.

Referring now to FIGURE 4, the horizontal pass 140 is substantially perpendicular to the vertical pass 142 so that the intermediate pass 144 between pinch roll sets 146, 148 is utilized in drastically changing the direction of the strip B while also changing the pass plane of the strip.

Motors

150, 152 are controlled by a sensing device 154 to maintain the proper shape of the natural loop F. In this embodiment, the natural loop is formed into approximately a 180 bend and then into a reversed 90 bend. At each of these bends, the natural loop must be formed so that there is no stretching or kinking of the strip. Of course, that exact path of the loop can be controlled to a certain extent by guide rolls and similar apparatus without destroying the characteristics of the natural loop. It is appreciated that the natural loop may be formed to bring either edge of the strip to the top of pinch roll 148. This reversal of the strip is easily accomplished in the other embodiments of the invention.

It is appreciated that various changes may be made in the illustrated embodiments of the present invention without departing from the intended spirit and scope of the present invention as defined in the appended claims.

Having thus described my invention, I claim:

1. A method of changing the pass plane of a metal strip moving through a processing line from a first plane to a second plane oblique to said first plane comprising the steps of guiding a first section of said metal strip along said first plane, driving the first section of metal strip at a predetermined line speed and under line tension, guiding a second and subsequent section of said metal strip along said second plane, driving said second section of said metal strip at a predetermined line speed and under line tension, forming a low tension natural loop in said metal strip between said sections,with said strip being twisted in said loop between a substantially horizontal and a substantially edgewise disposition and correlating the speeds of said sections to maintain said natural loop.

2. A method of changing the pass plane of a metal strip moving through a processing line from a first plane to a second plane oblique to said first plane comprising the steps of providing two sets of pinch rolls with the nip of one set substantially in the first plane and the nip of said second set substantially in the second plane, driving the rolls at substantially the same linear surface speed, forming the metal strip between said roll sets into a natural loop wherein the length of the strip between the rolls is substantially greater than the length of a straight line extending between the nips of the roll sets and with said strip being twisted in said loop between a substantially horizontal and a substantially edgewise disposition, and controlling the speed of the roll sets to maintain this greater length of the metal strip between the roll sets.

3. A method of processing metal strip comprising conveying said metal strip in a horizontal pass plane to a set of substantially horizontal pinch rolls, forming a natural loop in said metal strip as it leaves said pinch roll set, terminating said natural loop at a substantially vertical set of pinch rolls, controlling the speed of said pinch roll sets to maintain said natural loop at a predetermined size and under very little tension, and then passing said metal strip in an edgewise posture through a processing operation.

4. A method of processing metal strip comprising conveying said metal strip in a horizontal pass plane to a set of substantially horizontal pinch rolls, forming a natural loop in said metal strip as it leaves said pinch roll set, terminating said natural loop at a substantial vertical set of pinch rolls, controlling the speed of said pinch roll set to maintain said natural loop at a predetermined size and under very little tension, passing said metal strip in an edgewise posture through a processing operation to a second set of vertical pinch rolls, forming a second natural loop in said metal strip as the metal strip leaves said second vertical pinch roll set, terminating said second natural loop at a second substantially horizontal set of pinch rolls, and controlling the speed of said second pinch roll sets to maintain said second natural loop at a predetermined size and under very little tension.

5. An apparatus for obliquely changing the pass plane of a metal strip moving through a processing line comprising a first and second set of pinch rolls spaced from each other to define an intermediate pass in said processing line, said pinch roll sets being obliquely disposed with respect to each other to define the desired change in the pass plane, means for controlling the relative speed of said pinch rolls to maintain a tension in the strip of said intermediate pass substantially below the line tension in said processing line.

6. An apparatus as defined in claim 5 wherein said tension is substantially zero and due primarily to the 0 weight of said metal strip in said natural loop.

7. An apparatus as defined in claim 5 wherein said means comprises a device for sensing the transverse position of said metal strip between said pinch roll sets, and a device for changing the relative speed of said pinch roll sets in response to a predetermined change in the transverse. position of said metal strip.

8. An apparatus for obliquely changing the pass plane of a metal strip moving through a processing line from a first plane to a second plane comprising first means for forming a low tension, natural loop in said metal strip between said pass planes with said strip being twisted in said loop between a substantially horizontal and a substantially edgewise disposition, and second means for maintaining the size of said natural loop within predetermined limits, said first means including a first set of pinch rolls 'with a nip in said first plane, a second set of pinch rolls with a nip in said second plane, and said pinch rolls being spaced to allow the natural formation of said loop so that all longitudinal lines in said metal strip between said roll sets are substantially equal.

9. An apparatus for obliquely changing the pass plane of a metal strip moving through a processing line from a first plane to a second plane comprising first means for forming a low tension, natural loop in said metal strip between said pass planes with said strip being twisted in said loop between a substantially horizontal and a substantially edgewise disposition, and second means for maintaining the size of said natural loop within predetermined limits, said second plane extending in a direction angularly disposed. with respect to said first plane.

10. An apparatus as defined in claim 9 wherein said angular disposition is approximately 180.

11. An apparatus as defined in claim 9 wherein said angular disposition is approximately C.

References Cited by the Examiner UNITED STATES PATENTS 1,525,939 2/1925 Holmes 226-118 2,087,010 7/1937 Wardle 242-78.6 X 3,071,332 1/1963 Dain 226-118 X 3,105,625 10/1963 Miserocchi 226118 X M. HENSON WOOD, 111., Primary Examiner.

ROBERT B. REEVES, Examiner.

Claims

1. A METHOD OF CHANGING THE PASS PLANE OF A METAL STRIP MOVING THROUGH A PROCESSING LINE FROM A FIRST PLANE TO A SECOND PLANE OBLIQUE TO SAID FIRST PLANE COMPRISING THE STEPS OF GUIDING A FIRST SECTION OF SAID METAL STRIP ALONG SAID FIRST PLANE, DRIVING THE FIRST SECTION OF METAL STRIP AT A PREDETERMINED LINE SPEED AND UNDER LINE TENSION, GUIDING A SECOND AND SUBSEQUENT SECTION OF SAID METAL STRIP ALONG SAID SECOND PLANE, DRIVING SAID SECOND SECTION OF SAID METAL STRIP AT A PREDETERMINED LINE SPEED AND UNDER LINE TENSION, FORMING A LOW TENSION NATURAL LOOP IN SAID METAL STRIP BETWEEN SAID SECTIONS, WITH SAID STRIP TWISTED IN SAID LOOP BETWEEN A SUBSTANTIALLY HORIZONTAL AND A SUBSTANTIALLY EDGEWISE DISPOSITION AND CORRELATING THE SPEEDS OF SAID SECTIONS TO MAINTAIN SAID NUTURAL LOOP.