WO2012087032A2

WO2012087032A2 - Complex roll

Info

Publication number: WO2012087032A2
Application number: PCT/KR2011/009950
Authority: WO
Inventors: 김용호; 한상재; 이규복
Original assignee: 일진다이아몬드(주)
Priority date: 2010-12-21
Filing date: 2011-12-21
Publication date: 2012-06-28
Also published as: WO2012087032A3; KR20120070208A

Abstract

The present invention relates to a complex roll comprising: a roll shaft having threaded surfaces formed at both sides of an outer surface thereof and spaced apart from each other, and a collar portion formed between the threaded surfaces; a plurality of rolling rings assembled to both sides about the collar portion; spacer rings assembled to the respective sides of each of the rolling rings, opposed to the sides of each of the rolling rings directed toward the collar portion; clamping nuts, each of which being arranged at the side of the spacer ring opposed to the side of the spacer ring directed toward the rolling ring, and each of which having a threaded surface to be fastened to the threaded surface of the roll shaft; and side keys interposed between each rolling ring and the collar portion and between each rolling ring and each spacer ring.

Description

Composite roll

The present invention relates to a composite roll, and more particularly to a composite roll that is firmly assembled.

There are various kinds of rolls used in the rolling process. First, the one-piece roll is easy to manufacture because the shaft and the rolling ring are integrally formed. In particular, the DCI roll (ductile cast iron roll), adamite roll (adamite roll), chilled roll (chilled roll), etc. are formed as an integral roll by casting. However, these unitary rolls have low wear resistance, which reduces the replacement cycle of the rolls and lowers productivity.

Composite rolls, another type of roll used in the rolling process, are manufactured by separately manufacturing a roll shaft and a rolling ring, and then using the rolling ring by assembling the roll shaft. In particular, the rolling ring is formed using a material having high wear resistance. However, it is not easy to assemble the rolling ring on the roll shaft so that the roll shaft and the rolling ring are kept firm. In other words, during the rolling process, the rolling ring does not rotate integrally with the roll shaft, but turns away, thereby making it difficult to effectively proceed with the rolling process. In addition, when this phenomenon is repeated for a long time, the roll shaft may be damaged or the rolling ring may be separated from the roll shaft, resulting in a rolling accident.

As a result, there is a limit to efficiently proceeding the rolling process using a rolling roll.

The present invention can provide a firmly assembled composite roll.

The present invention provides a roll shaft having a screw surface formed on both sides of the outer peripheral surface to be spaced apart from each other and the collar formed between the two screw surfaces, a plurality of rolling rings assembled on both sides of the collar portion, the side of each rolling ring A spacer ring assembled on an opposite side of the surface facing the collar portion, disposed on an opposite surface of the side of each spacer ring facing the rolling ring, having a screw surface, and screwed with the screw surface of the roll shaft. Disclosed is a composite roll comprising a clamping nut and a side key disposed between each rolling ring and the collar portion and between each rolling ring and each spacer ring.

In the present invention, a horizontal key may be disposed between the roll shaft and the spacer ring.

In the present invention, it may further include a setting bolt which is arranged to pass through the clamping nut at the side of the clamping nut in a direction parallel to the axis of rotation of the work roll direction of the composite roll and coupled to the side of the spacer ring.

In the present invention, a plurality of setting bolts may be disposed.

In the present invention may further include a locking bolt disposed on the side of the clamping nut in a direction perpendicular to the rotation axis of the work roll direction of the composite roll.

In the present invention, a sleeve may be disposed between the locking bolt and the roll shaft.

In the present invention, the locking bolt may be disposed to face the screw surface of the roll shaft.

In the present invention, the diameter of the collar portion may be formed smaller than the diameter of the rolling ring.

In the present invention, the rolling ring may contain tungsten carbide.

In the present invention, a side keyway in which the side key is disposed may be formed on a side facing the collar portion of the rolling ring and a side facing the spacer ring.

In the present invention, the side keyway includes two first side keyways formed on the side facing the spacer ring and two second side keyways formed on the side facing the collar, and the two first side keys. Ways may be arranged on the same line as each other, the two second side key ways may be arranged on the same line with each other, and the first side key way and the second side key way may be arranged to be perpendicular to each other.

In the present invention, the side key may be in the form of a half moon key and the side key way may have a curved surface.

In the present invention, the side key may be spaced apart from the side key way in the corner region of the side key way.

In the present invention, the side key has a curved cross section, and the cross section of the curved line has an area having a different radius, and in a portion of the curved cross section where the side keyway is in contact, the side key has the same radius as the side keyway. It may have a radius, and may have a radius smaller than the radius of the side keyway in the area of the curved section spaced apart from the side keyway.

In the present invention may further comprise a half ring assembled between the clamping nut and the spacer ring.

In the present invention, after placing the jacking bolt to penetrate the clamping nut on the side of the clamping nut and contact with the side of the spacer ring, the half ring is assembled after applying pressure to the spacer ring using the jacking bolt, After removing the jacking bolt after assembling the half ring, the setting bolt may be assembled at the position where the jacking bolt is disposed.

In the present invention may have a symmetrical structure around the collar portion.

In the present invention, the rolling ring may be disposed one by one on both sides of the collar part about the collar part.

The composite roll according to the present invention is firmly assembled to provide efficiency in the rolling process.

1 is a schematic cross-sectional view showing a composite roll according to one embodiment of the present invention.

FIG. 2 is an enlarged view of C of FIG. 1.

3 is an enlarged view of a portion D of FIG. 1.

4 is a cross-sectional view taken along the line IV-IV of FIG. 1.

5 is an enlarged view of the rolling ring of FIG. 1.

FIG. 6 is a perspective side view seen from the direction A of FIG. 5.

7 is a cross-sectional view taken along the line VII-VII of FIG. 6.

8 is a view showing another modified example of the rolling ring and the spacer ring in the configuration of the composite roll of FIG.

9 to 13 are views sequentially illustrating a process of assembling the composite roll of FIG.

Hereinafter, with reference to the embodiments of the present invention shown in the accompanying drawings will be described in detail the configuration and operation of the present invention.

1 is a schematic cross-sectional view illustrating a composite roll according to an embodiment of the present invention, FIG. 2 is an enlarged view of C of FIG. 1, FIG. 3 is an enlarged view of D of FIG. 1, and FIG. 4 is 1 is a cross-sectional view taken along the line IV-IV of FIG. 1, FIG. 5 is an enlarged view of the rolling ring of FIG. 1, FIG. 6 is a side view viewed from the direction A of FIG. 5, and FIG. It is a cross-sectional view cut along the line.

1 to 7, the composite roll 100 includes a roll shaft 101, a rolling ring 110, a spacer ring 120, a clamping nut 130, a half ring 140, a setting bolt 150, and locking. Bolt 160, side key 170 and horizontal key 180.

The roll shaft 101 has a collar unit 102 in the central region. The screw surface 101a is formed in the both outer peripheral surfaces centering on the collar part 102 of the roll shaft 101. As shown in FIG. The threading direction of the screw surface 101a is made to be opposite to the working direction WS in which the composite roll 100 rotates. This prevents the screw coupling of the roll shaft 101 and the clamping nut 130 to be separated during the rolling process using the composite roll 100.

Rolling rings 110 are disposed on both sides of the collar portion 102 of the roll shaft 101. That is, two rolling rings 110 are disposed on the left side and the right side of the collar portion 102 with the collar portion 102 interposed therebetween. In addition, the present invention is not limited thereto, and four or more rolling rings 110 may be disposed to be symmetrical to the left and right sides of the collar portion 102 with the collar portion 102 interposed therebetween. Rolling ring 110 is formed using a material having excellent wear resistance. Specifically, the rolling ring 110 may include a cemented carbide such as tungsten carbide. Side keys 170 are disposed at both sides of the rolling ring 110. Details thereof will be described later.

The diameter of the rolling ring 110 is larger than the diameter of the collar 102. That is, in the state in which the rolling ring 110 is disposed on the roll shaft 101, the extension line of the edge of the rolling ring 110 is spaced apart from the collar 102. This prevents damage to the collar portion 102 through repetition of the rolling process to increase the use cycle of the roll shaft 101 can be easily reused.

A spacer ring 120 is disposed on the roll shaft 101. Specifically, the spacer ring 120 is disposed on the outer side of the rolling ring 110, that is, on the opposite side of the surface of the rolling ring 110 toward the collar portion 102. The spacer ring 120 may be formed using steel. In addition, the diameter of the spacer ring 120 is smaller than the diameter of the rolling ring 110. This may prevent damage to the spacer ring 120 during the rolling process.

The horizontal key 180 is disposed in the space between the spacer ring 120 and the roll shaft 101. During the rolling process, the spacer ring 120 does not rotate integrally with the roll shaft 101 and the spacer ring 120 is in error. In the present invention, the spacer ring 120 is moved through the horizontal key 180. It rotates integrally with the roll shaft 101 without turning.

In addition, since the spacer ring 120 is formed of steel, even if the horizontal key 180 is disposed between the spacer ring 120 and the roll shaft 101, the spacer ring 120 may be formed due to the horizontal key 180 during rotation of the composite roll 100. 120 easily prevents breakage.

A clamping nut 130 is disposed on the roll shaft 101. Specifically, the clamping nut 130 is disposed on both sides of the spacer ring 120, that is, on the opposite side of the surface of the spacer ring 120 that faces the rolling ring 110. The screw surface 131 is formed on the inner circumferential surface of the clamping nut 130. The threaded surface 131 of the clamping nut 130 and the threaded surface 101a of the roll shaft 101 are coupled to each other. Through this, the clamping nut 130 and the roll shaft 101 are safely coupled. In addition, the rolling ring 110 and the spacer ring 120 are not separated from the roll shaft 101 by the clamping nut 130.

As described above, the thread direction of the screw surface 131 and the screw surface 101a is opposite to the working direction WS in which the composite roll 100 rotates so that the roll shaft 101 and the clamping nut 130 are rolled during rolling. Prevent separation.

The setting bolt 150 is disposed to penetrate the side surface of the clamping nut 130, that is, the side surface of the clamping nut 130 in a direction parallel to the rotation axis of the working direction WS of the composite roll 100. The setting bolt 150 passes through the clamping nut 130 and is coupled to the side of the spacer ring 120. Through this, the clamping nut 130 and the spacer ring 120 are firmly coupled, and the coupling between the clamping nut 130 and the roll shaft 101 is also strengthened. Although not shown in FIG. 2, after setting the setting bolt 150, a sealant (not shown) may cover the top surface of the setting bolt 150.

In addition, the locking bolt 160 is disposed on the other side of the clamping nut 130, that is, the side of the clamping nut 130 in a direction orthogonal to the rotation axis of the working direction WS of the composite roll 100. The locking bolt 160 further tightens the screw coupling of the clamping nut 130 and the roll shaft 101, that is, the coupling between the screw surface 101a and the screw surface 131. A sleeve 161 is disposed between the locking bolt 160 and the threaded surface 101a of the roll shaft 101 to easily prevent the threaded surface 101a of the roll shaft 101 from being damaged.

A half ring 140 is disposed between the clamping nut 130 and the spacer ring 120. Before the setting bolt 160 is coupled, the jacking bolt (not shown) or the jacking screw (not shown) is placed in the setting bolt 160 position, and then the gap between the clamping nut 130 and the spacer ring 120 is used. Install half ring 140, then remove jacking bolts or screws.

Referring to FIG. 4, the position and quantity of the setting bolt 150 and the locking bolt 160 disposed on the clamping nut 130 are illustrated. Eight setting bolts 150 are disposed on the side surface of the clamping nut 130. The present invention is not limited thereto, and the number of setting bolts 150 may be adjusted in multiples of four, and for example, four setting bolts 150 may be disposed.

The four locking bolts 160 are disposed not to overlap with the setting bolts 150. In this embodiment, of course, the setting bolt 150 and the locking bolt 160 are equally disposed on both clamping nuts 130 around the collar 102 of the roll shaft 101.

The side key 170 will be described in detail with reference to FIGS. 5 to 7. For convenience of description, the side key 170 is not illustrated in FIGS. 5 and 6. The rolling ring 110 of FIG. 5 also shows the right rolling ring 110 of the two rolling rings 110 of FIG. 1.

The rolling ring 110 is provided with the some caliber 111 so that a rolling process may progress.

Two first side keyways 171 and two second side keyways for placing the side keys 170 on both sides of the rolling ring 110, that is, the side facing the collar portion 102 and the opposite side thereof. 172 is formed.

The first side keyway 171 is formed on the right side of the side of the rolling ring 110, that is, the side facing the adjacent spacer ring 120 of the side of the rolling ring 110 shown in FIG. 5. The two first side key ways 171 are located on the same line as each other. The second side keyway 172 is formed on the left side of the side surface of the rolling ring 110. The two second side key ways 172 are colinear with each other.

In addition, the first side key way 171 and the second side key way 172 may be formed to be orthogonal to each other without being located next to each other. This allows the side keys 170 and the adjacent members to be subjected to a balanced stress during the rolling process.

Side keys 170 are disposed on the first side key way 171 and the second side key way 172 as illustrated in FIG. 1. Although not shown, when the side key 170 is disposed on the first side key way 171, a side key way (not shown) is formed in the spacer ring 120 to correspond to the side key 170. The side key 170 is disposed on the first side key way 171 so that the rolling ring 110 and the spacer ring 120 do not rotate separately from each other. That is, when the roll shaft 101 rotates during the rolling process, the rolling ring 110 and the spacer ring 120 are prevented from turning or rotating independently of each other, and the rolling ring 110 and the spacer ring 120 rotate integrally. do.

Although not shown, when the side key 170 is disposed on the second side key way 172, the side key way (not shown) is also formed on the collar 102 of the roll shaft 101 to correspond to the side key 170. Of course. The side key 170 is disposed on the second side key way 172 so that the roll shaft 101 and the rolling ring 110 do not rotate separately from each other. That is, when the roll shaft 101 rotates during the rolling process, the rolling ring 110 is prevented from turning or rotating separately from the roll shaft 101 and the rolling ring 110 and the roll shaft 101 are rotated integrally. .

5 and 6, the

side keyways

171 and 172 have a curved boundary line, and a half moon side key 170 is disposed to correspond to the rolling ring 110 by the side key 170 during rotation. This prevents the damage or the side key 170 from being broken.

In particular, referring to FIG. 7, one side of the side key 170 and the side key way 171 contacting each other is formed to have a different radius. This prevents the side keyway 171 from being broken by the side key 170 and, as a result, the rolling ring 110 from being broken. 7 will be described in detail. One side of the side key way 171 has a width W and a depth D. The side surface of the side keyway 171 is formed as a curved surface having a radius R1 in the entire width W. FIG. The side key 170 is equal to the radius R1 of the side keyway 171 in the central region but has a smaller radius R2 in the outer region. Specifically, it has a radius R2 in an area 1/10 of the width W from both side edges of the side keys 170. It also has a radius R2 in the area 2/10 of the height H of the portion of the overall height of the side key 170 which does not enter the side key way 171. Here, the height H of the area of the side key 170 not included in the side key way 171 is also a portion disposed on the key way (not shown) of the spacer ring 120.

Through the shapes of the side keyway 171 and the side key 170, the side keys 170 are damaged by the side keys 170 while the composite roll 110 rotates during the rolling process. Easily prevented.

In the present embodiment, the side key 170 is disposed between the rolling ring 110 and the spacer ring 120. However, the present invention is not limited thereto, and a pin may be disposed between the rolling ring 110 and the spacer ring 120.

FIG. 8 is a view illustrating another modified example of the rolling ring and the spacer ring in the configuration of the composite roll of FIG. 1, and shows that the side pins 190 are disposed on the rolling ring 110 and the spacer ring 120. For convenience of description, one rolling ring 110 and one spacer ring 120 are illustrated.

The pinhole 191 is formed on the side of the rolling ring 110 and the sleeve 192 is disposed in the pinhole 191 to prevent the surface of the rolling ring 110 from being damaged by the side pin 190. The side pin 190 is disposed over the rolling ring 110 and the spacer ring 120.

Like the side key 170, the side pin 190 also prevents the rolling ring 110 and the spacer ring 120 from rotating separately from each other. The number of side pins 190 is preferably arranged in an even number per side of one rolling ring (110). In addition, the side key 170 and the side pin 190 may be simultaneously disposed on one side of the rolling ring 110.

9, the roll mounting stand 200 is prepared to facilitate the assembly process. After the roll shaft 101 is washed, the roll shaft 101 is disposed in a direction perpendicular to the roll mounting stand 200. First, the side key 170 is disposed at the center of the roll shaft 101, that is, the collar 102. As described above, the side key 170 is disposed on a keyway (not shown) formed in the collar 102.

10, the rolling ring 110 and the spacer ring 120 are disposed on the roll shaft 101.

First, the rolling ring 110 is disposed on the roll shaft 101 to be in close contact with the collar 102 and the side key way 170. At this time, it is preferable to interpose an adhesive material such as loctite between the rolling ring 110 and the roll shaft 101.

The side key 170 is then placed on the other side of the rolling ring 110. In addition, the horizontal key 180 is disposed on the side of the roll shaft 101 on which the spacer ring 120 is to be disposed. The spacer ring 120 is then placed. Although one spacer ring 120 is shown, a plurality of spacer rings 120 may be used. In addition, the spacer ring 120 may also increase according to the number of the rolling rings 110.

Then, referring to FIG. 11, the clamping nut 130 is disposed on the roll shaft 101. The screw surface formed on the inner circumferential surface of the clamping nut 130 and the screw surface formed on the side of the roll shaft 101 are screwed together.

Then, referring to FIG. 12, the jacking bolt 151 may be used, ie, the jacking bolt 151 may be tightened to remove the spaced space that may occur between the rolling ring 110 and the spacer ring 120. In this case, a plurality of jacking bolts 151 may be arranged to balance the force, and specifically, the jacking bolts 151 may be arranged to be a multiple of four. In addition, the backlash is removed using the jacking bolt 151, and the gap between the spacer ring 120 and the clamping nut 130 is opened.

After this gap is opened, the half ring 140 is assembled between the spacer ring 120 and the clamping nut 130. Due to the fitting of the half ring 140, a predetermined pressure is applied to the spacer ring 120, the rolling ring 110, and the clamping nut 130.

Then, referring to FIG. 13, the setting bolt 150 and the locking bolt 160 are assembled. That is, after removing the jacking bolt 151 of FIG. 12, the setting bolt 150 is coupled to the side surface of the spacer ring 120 through the clamping nut 130. Then, the sealant 152 is formed on the upper surface of the setting bolt 150. The sealant 152 is preferably silicon based.

In addition, the locking bolt 160 is disposed on the side of the clamping nut 130 so that the screw surface of the clamping nut 130 and the screw surface of the roll shaft 101 are more firmly coupled. The sealant 162 is formed on the upper surface of the locking bolt 160.

Through this process, the assembly process in one direction of the roll shaft 101 is completed. Although not shown, the roll shaft 101 is turned upside down and the assembly process in the other direction is performed in the same manner as described above to finally form the composite roll of the present invention.

The composite roll 100 of the present invention arranges the rolling rings 110 on both sides of the collar portion 102 of the roll shaft 101 and then assembles the clamping nuts 130 on both sides. As a result, uniform stress is applied to the roll shaft 101 and the clamping nut 130, thereby preventing deformation of the composite roll 100, which occurs when stress is unevenly applied to one side, resulting in durability of the composite roll 100. This is improved.

In addition, the side keys 170 are disposed on both sides of the rolling ring 110 to prevent the rolling ring 110, the roll shaft 101, the rolling ring 110, and the spacer ring 120 from being misused with each other. That is, due to the load due to the material for rolling during the rolling process, the rolling ring 110 is prevented from running and the rolling ring 110 is rotated integrally with the roll shaft 101 and the spacer ring 120. Through this, an effective rolling process using the composite roll 100 is possible. In particular, the side key 170 is formed in a half moon shape to prevent the side surface of the rolling ring 110 from being damaged, and further, the side key 170 and the side

key ways

171 and 172 have different radii at one contact surface. The edge damage of the

key ways

171 and 172 is effectively prevented.

In addition, a horizontal key 180 is disposed between the spacer ring 120 and the roll shaft 101 to prevent the spacer ring 120 and the roll shaft 101 from being rotated separately from each other, thereby preventing the spacer ring 120 from being idle. . Through this, the spacer ring 120 and the roll shaft 101 rotate integrally. As a result, the rolling ring 110 rotates integrally with the roll shaft 101 and the spacer ring 120 during the rolling process, thereby increasing the efficiency of the rolling process.

In addition, the setting bolt 150 is installed on the clamping nut 130 so that the clamping nut 130 and the spacer ring 120 are firmly coupled, and the clamping nut 130 is firmly coupled with the roll shaft 101. do. Since the firmness of the coupling of the clamping nut 130 and the roll shaft 101 is easily ensured, it is not necessary to apply excessive pressure on the side of the clamping nut 130 to fix the clamping nut 130. This prevents an abnormal load from being applied to the entirety of the composite roll 100 including the clamping nut 130 and the roll shaft 101.

In addition, the locking bolt 160 is installed on the clamping nut 130 so as to be spaced apart from the setting bolt 150 to improve the coupling force between the clamping nut 130 and the roll shaft 101. Through this, it is possible to form the composite roll 100 is finally firmly assembled.

Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

The present invention provides a roll shaft having a screw surface formed on both sides of the outer peripheral surface to be spaced apart from each other and the collar formed between the two screw surfaces, a plurality of rolling rings assembled on both sides of the collar portion, the side of each rolling ring A spacer ring assembled on an opposite side of the surface facing the collar portion, disposed on an opposite surface of the side of each spacer ring facing the rolling ring, having a screw surface, and screwed with the screw surface of the roll shaft. Provided is a composite roll comprising a clamping nut and side keys disposed between each rolling ring and the collar portion and between each rolling ring and each spacer ring.

Claims

A roll shaft having a screw surface formed on both sides thereof so as to be spaced apart from each other on an outer circumferential surface, and a collar portion formed between the screw surfaces on both sides thereof;

A plurality of rolling rings assembled on both sides of the collar part;

Spacer rings assembled on opposite sides of surfaces of the rolling rings toward the collar portion;

A clamping nut disposed on an opposite side of the side of each spacer ring facing the rolling ring, the clamping nut having a threaded surface and screwed to a threaded surface of the roll shaft; And

And a side key disposed between each rolling ring and the collar portion and between each rolling ring and each spacer ring.
According to claim 1,

And a horizontal key disposed between the roll shaft and the spacer ring.
According to claim 1,

And a setting bolt arranged to penetrate the clamping nut at the side of the clamping nut in a direction parallel to the axis of rotation of the composite roll in the working rotation direction and engaged with the side of the spacer ring.
The method of claim 3, wherein

And a plurality of setting bolts are arranged.
According to claim 1,

And a locking bolt disposed on a side surface of the clamping nut in a direction perpendicular to a rotation axis in the working rotation direction of the composite roll.
The method of claim 5,

And a sleeve is disposed between the locking bolt and the roll shaft.
The method of claim 5,

And the locking bolt is disposed facing the threaded surface of the roll shaft.
According to claim 1,

The diameter of the collar portion is formed smaller than the diameter of the rolling ring composite roll.
According to claim 1,

The rolled ring is a composite roll containing a cemented carbide.
According to claim 1,

And a side keyway on which a side key is disposed on a side facing the collar portion of the rolling ring and a side facing the spacer ring.
The method of claim 10,

The side keyway includes two first side keyways formed on the side facing the spacer ring and two second side keyways formed on the side facing the collar portion,

The two first side key ways are arranged collinear with each other, and the two second side key ways are collinear with each other,

And the first side keyway and the second side keyway are orthogonal to each other.
The method of claim 10,

Wherein the side key is in the form of a half moon key and the side key way has a curved surface.
The method of claim 10,

And the side key is spaced apart from the side key way in an edge region of the side key way.
The method of claim 13,

The side key has a curved cross section,

The cross section of the curve has regions with different radii,

A portion of the cross section of the curve in which the side keyway is in contact with the radius of the side keyway and a radius smaller than the side keyway in the area of the curve spaced apart from the side keyway Composite roll.
According to claim 1,

And a half ring assembled between the clamping nut and the spacer ring.
The method of claim 15,

Arranging the jacking bolt through the clamping nut at the side of the clamping nut and in contact with the side of the spacer ring, and then applying the pressure to the spacer ring using the jacking bolt, assembling the half ring,

And the setting bolt is assembled at the position where the jacking bolt is disposed after the jacking bolt is removed after assembling the half ring.
According to claim 1,

Composite roll having a symmetrical structure around the collar portion.
According to claim 1,

The rolling roll is disposed one by one on both sides of the collar portion around the collar portion.