Winding method for uniform properties

(54) Title: METHOD FOR WINDING A CONTINUOUS BLANKET MATERIAL TO FORM A COIL, AND, WINDING BLANKET MATERIAL COIL (51) Int.CI .: B65H 23/195 (30) Unionist Priority: 02/02/2007 US 60 / 899,315, 07/03/2007 US 11 / 825,129 (73) Owner (s): KIMBERLY-CLARK WORLDWIDE, INC.

(72) Inventor (s): NEAL JAY MICHAL, III; BALAJA KOVIL-KANDADAI; ROBERT JAMES COXE (85) National Phase Start Date: 07/23/2009 “METHOD FOR WINDING CONTINUOUS BLANKET MATERIAL FOR

FORM A COIL, AND, WRAPPED MATERIAL COIL ”

REFERENCES TO THE RELATED DEPOSIT REQUESTS

The present order hereby claims the priority of pending Interim Order US

serial number 60 / 899,315, filed on February 2, 2007.

DECLARATION CONCERNING THE RESEARCH SUBSIDIATED BY THE GOVERNMENT

FEDERAL

BACKGROUND

Winding is the process of rotating a flat web on a rolled coil. The 10 rolled coils are the most efficient method for storing large quantities of continuous blanket material in a package that is convenient for handling and transporting material. The coiled coil must be hard enough to withstand the handling of the coil, storage conditions, pressures of the coil forklift and automatic material handling systems. The wound coil becomes the delivery device as the material is unwound from the coil and further processed on a manufacturing line, such as in a conversion process.

Although each coiled coil is its own unique entity, it is common practice in the film and newspaper industry to qualify a coil as a hard coil or a soft coil. This is done based on the feel or hardness of the wound coil. A hard coil is also commonly called a fully compressed coil. Typically, reels rolled of paper, newsprint, laminated spinning spinning via continuous blow-spinning (SMS) are included in the category of soft reels. Polyester wound coils and film laminates are included in the category of fully compressed coils, which are called hard coils. Also, coils 25 of low-modulus films, film laminates, vertical film / filament laminates (VFL's) and extension bond laminates (SBL's) are included in the hard reel category. A hard coil is produced when the material's machine steering (MD) module is comparable to the material's radial module (ZD module) (Et = • Er). A soft coil is produced when the material's MD module is much larger than the material's radial module (Et >> Er).

The winding of continuous web materials in a wound coil results in stresses within the coil, and thus the winding presents an increased tension problem. For commercial grade continuous spinning, there is little concern about how tight the material is wrapped around the bobbin. However, when elastomeric, delicate laminates or highly aerated mat materials are wound, the coil structure (hardness) results in a permanent change in the material properties within the wound coil. This change can occur during the winding process, immediately after the winding process for a period of time.

Petition 870180050226, of 06/12/2018, p. 9/13

The tension in the outermost layer of a continuous blanket of material that is wound on a coil is known as "tension by winding" or "WOT". This WOT parameter includes the blanket tension and any additional tension that may occur due to the choke load (choke induced voltage), which depends on the type of winder. Each new layer added on the winding coil during the winding process changes the stresses within the wound coil.

The document by Zbigniew Hakiel (“Nonlinear model for wound coil stresses”, TAPPI Journal, Vol. 70 (5), pp 113-117, 1987) describes how the coil stresses wound at any diametrical location within the continuous blanket wrapped in a coil, the properties (listed under “required input values”) of the coil and the material can be calculated. Hakiel's document discusses both the computational method and the flowchart for recording a computer program in any computer language, and thus, a simple program can be recorded to estimate the coil voltages based on what is described in Hakiel's document. A graph of these stresses as a function of the coil diameter of continuous material procedures produces a curve that exhibits a characteristic shape of both the pressure between layers (stress / radial pressure) and stress in the machine direction (MD). The tension in the MD is the tension in the direction where the blanket is wound over the coil or removed from the coil and is also known as the tangential tension or the circumferential tension.

From the point of view of the wound coil structure, a “soft” coil has a plateau-type radial tension profile. The addition of more blanket material rolled over the coil does not increase the radial stresses within these types of coils. The only limitation on the size of the bobbin results from the limitations of the bobbin and the limitations of handling and transport units of the mat. On the other hand, a "hard" coil has a tapered radial tension profile. The addition of the blanket material to the coil directly influences the radial tension profile by increasing the tension inside the coil. So, in the case of hard coils, problems like "coil lock" and "core crushing" do not need to be addressed. Concerns about these problems tend to restrict the size of the "hard" coils wound.

In the case of soft coils, the coil voltage (also referred to as “voltage in the

MD ”or“ tangential stress ”or“ circumferential stress ”) is uniform throughout the coil, except very close to the core and outside diameter. In many cases the coil voltage is close to zero and can sometimes still be negative. In contrast, in hard coils, the tension and deformation in the MD along the coil produces a curve that resembles a 'Nike®-Swoosh®' profile. If the coiled coil has to be made of films with high modulus, the deformation swoosh profile on the MD is not a major concern since the deformations at the beginning are small. As the material is unrolled, this deformation is typically quickly recovered. So, the winding process does not need to undergo any modification to accommodate this deformation stored in the coil.

However, this is not the case in winding films with low modulus, film laminates, VFL and SBL. For example, the MD module of the VFL material is in the range of about 5 psi to about 25 psi, which is very low. The outside diameter of a wound coil of VFL material can be approximately 62 inches. The elastomeric filaments in the VFL material make them behave like a rubber band. As anyone who wraps a rubber band around one of the fingers can confirm, the pressures on a coiled coil of VFL material are very high, even if the material is wound on the coil in low tension by means of coiling (WOT).

The stresses in the MD in coils of such blankets of material will induce the attributes (elasticity, for example) of the blanket material on the coil to change “along the coil”, that is, the attributes of the material wrapped around the core of the material. coil will commonly differ from the same attributes of the material wrapped around the outer diameter of the coil and will vary in intermediate diameters of these two extreme diameters. Since the strains are very high and many materials are highly viscoelastic, the strains stored inside the coil become permanent. This results in properties of aged material that vary (repeatedly) as a function of the bobbin radius. In order to deal with such properties in the processing of blankets extracted from such hard coils, special modifications of the process equipment (such as controlled unwinding) are not necessary during conversion, for example. The problem of dealing with such properties becomes complicated if printing is done on the blanket during conversion. Since deformation recovery rates are different due to the ten25 being in a different coil that the mat was submitted to, the repeated length of the printed symbols may not be the same as the mat material is unwound from the coil.

As noted above, blankets made of elastomeric materials that are wound in coils will experience some permanent change in the material's properties. The elastic properties of the material wound around the core of the coil will commonly differ by more than twenty percent of the elastic properties of the material wound around the outside diameter of the coil. In other words, the elastic properties "along the coil" commonly vary by more than twenty percent. In addition, the elastic properties in the machine direction (MD) are generally important in the final conversion process. A change in elastic properties as the material is unwound from the coil for use in an equipment processing line will generally cause waste and / or line downtime.

Empirical studies have been carried out to develop a winding procedure that results in uniform material properties “along the coil”, that is, from the outside diameter to the core of the wound coil. However, conducting such studies for each new differently sized coil of differently composed material is tedious, time-consuming and in many cases unfeasible.

BRIEF DESCRIPTION SUMMARY

The winding procedure that has been developed results in substantially uniform material properties from the outside diameter to the core of a wound coil of elastomeric blankets produced by vertical film lamination (VFL) or bonding under extension lamination (SBL) or a film registered. A computer model based on the document by Zbigniew Hakiel (“Nonlinear model for wound coil stresses”, TAPPI Journal, Vol. 70 (5), pp 113-117, 1987) can be used to estimate the profile along the coil of elastomeric blankets produced by VFL, SBL, or as a registered film. Based on the concept called “WOT Transposition”, a modified version of the model of

Hakiel can be used to correct the constant WOT winding profile in order to obtain a controlled WOT winding profile (also known as plywood) that can be used to wind material onto a coil that exhibits properties (including MD stress on the mat) ) that are substantially uniform across the coil.

It is desirable to use a computer program to carry out this transposition.

One embodiment of such a computer program is attached to that as Appendix A and this is referred to here as the coiler computer program. This resulting controlled winding technique has immediate application of such blankets that are converted into child care products, adult care products and child care products.

The modified Hakiel calculation model requires WOT input values ​​where each diametrical section of the blanket is wound over the coil, the material properties of the blanket and the dimensions of the wound coil. For a steady-state winding condition to wrap a blanket to form a coil, the WOT is constant. However, when organized as a function of the bobbin diameter, the properties along the bobbin of the material that is wound on the bobbin may have a unique feature that is not uniform. In particular, significant non-uniformity is a common feature of rolled coils of elastomers and film.

When the coiled coil of a blanket produced by VFL, SBL or as a registered film is produced in constant WOT, the tension in the blanket adjacent to the core of the coil and in the outer diameter of the coil is normally the same as the WOT if wound over a sufficiently rigid core . Elsewhere inside the coiled coil, the tension in the blanket is less than the WOT, and so it can be said that there is a reduction in tension along the coil. This reduction occurs because the outer layers in the coil compress the layers below it. To make the tension in the blanket inside the coiled coil uniform regardless of where the tension is measured in the coil, that is, to make the tension across the coil uniform, the WOT needs to be controlled to compensate for the reduction in tension along the coil that could be created when the coil was wound in constant WOT. This clearing technique is called “WOT transposition”. When the mat material is wound on the coil using a compensated WOT profile, it varies with the mat diameter so that it is calculated using the WOT transposition, then the MD tension along the coil of the resulting mat material within the wound coil. becomes substantially uniform.

Additional objectives and advantages of the present description will be presented in part in the description below, and in part will be evident from the description, or can be learned by practicing this description.

The attached drawings, which are incorporated and constitute a part of this descriptive report, illustrate at least one currently preferred embodiment of the present description as well as some alternative embodiments. These drawings, together with the description, serve to explain the principles of the present description, but in no way are they intended to be exhaustive of all possible manifestations of the present description.

BRIEF DESCRIPTION OF THE DRAWINGS

A complete and convincing description of the present description, including its best mode for a person skilled in the art, is presented more particularly in the rest of the specification, including reference to the attached figures, in which:

Figure 1 shows schematically a wound coil with a continuous, elastic, viscoelastic or viscoplastic blanket and the directions of the three main stresses over a section of the blanket within the coil.

Figure 2 schematically shows the 10 Psi constant winding voltage (WOT) that was used during the wrapping of the mat with properties listed in Example One to produce the coil of Example One.

Figure 3 schematically shows the tension profile along the coil exclusive to the radial tension of a coil wound according to Example One which was wound at a voltage by means of a 10 psi constant winding (WOT).

Figure 4 shows schematically the voltage profile along the coil exclusive of the voltage in the MD of a coil wound according to Example One which was wound in a voltage through 10 psi constant winding (WOT).

Figure 5 schematically explains the concept of “WOT transposition” according to a modality of the present description.

Figure 6 shows schematically the tension by controlled winding (WOT) that was calculated according to a modality of the present description that will be used during the winding of a desired blanket modality that will be created according to a modality of the present description.

Figure 7 shows schematically the effect on radial stresses within a coil configured as in Example One that was wound using a WOT controlled according to the modality of Figure 6.

Figure 8 shows schematically the effect on the voltages in the MD inside a coil configured as in Example One that was wound using a WOT controlled according to the modality of Figure 6.

Figure 9 graphically presents a comparison between the winder stretches of a wound coil using a controlled WOT profile (depending on the diameter that is wound on the coil, for example, as in Figure 6) designed to produce tension in the uniform MD within the coil (bottom curve) and a coil wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil (upper curve).

Figure 10a graphically presents a first VFL material as a function of the diametrical position in the coil, a comparison between the deformation in the measured MD (curve of data points represented with a square) inside the coil of a rolled en20 coil using a WOT profile controlled (depending on the diameter that is wound on the coil, for example, as in Figure 6) and the deformation in the MD measured inside a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil.

Figure 10b shows graphically the same first VFL material and conditions as Figure 10a as a function of the diametrical position in the coil, a comparison between the deformation in the measured MD flow (curve of data points represented with a square) inside the coil. a coil wound using a controlled WOT profile (depending on the diameter that is wound on the coil, for example, as in Figure 6) and the deformation in the MD measured inside a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil.

Figure 10c shows graphically the same first VFL material and conditions as Figure 10a, but as a function of the coil length from the core to the free end, a comparison between the strain in the measured MD (curve of data points represented with a square) inside the coil of a coiled coil using a controlled WOT profile (for example, as in Figure 6) and the deformation in the MD measured from a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil.

Figure 10d shows graphically the same first VFL material and conditions 5 as Figure 10a, but as a function of the coil length from the core to the free end, a comparison between the deformation in the measured MD (curve of data points represented with a square) inside the coil of a coiled coil using a controlled WOT profile (depending on the diameter that is coiled over the coil, for example, as in Figure 6) and the deformation in the MD measured from a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil

Figure 10e is a table showing the data that are used for the curves of the data points represented with a diamond and data points represented with a square shown in Figures 10a to 10d.

Figure 11a graphically presents a second VFL material as a function of the diametrical position on the coil, a comparison between the deformation in the measured MD (curve of data points represented with a square) inside the coil of a coiled coil using a controlled WOT profile (depending on the diameter that is wound on the coil, for example, as in Figure 6) and the deformation in the MD measured inside a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil.

Figure 11b shows graphically the same second VFL material and conditions as Figure 11a, a comparison between the deformation in the measured MD flow (curve of data points represented with a square) of the blanket inside the coil of a coil wound using a controlled WOT profile (depending on the diameter that is wound on the coil, for example, as in Figure 6) and the deformation in the MD measured by the flow of the mat inside a coil (curve of data points represented with a rhombus) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil .

Figure 11c shows graphically the same second VFL material and conditions as Figure 11a, but as a function of the coil length from the core to the free end, a comparison between the deformation in the measured MD (curve of data points represented with a square) inside the coil of a coiled coil using a controlled WOT profile (for example, as in Figure 6) and the deformation in the

MD measured inside a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil.

Figure 11 d shows graphically the same second VFL material and conditions as Figure 11a, but as a function of the length of the coil from the core to the free end, a comparison between the deformation in the measured MD flow (curve of data points represented with a square) inside the coil of a coiled coil using a controlled WOT profile (depending on the diameter that is coiled over the coil, for example, as in Figure 6) and the deformation in the MD measured within a coil (curve of data points represented with a diamond) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound over the coil.

Figure 11e is a table showing the data that are used for the curves of the data points represented with a diamond and data points represented with a square shown in Figures 11a to 11d.

Figure 12 shows schematically in the form of a flowchart, the steps that can be adopted to practice a modality of the present description that produces a tension coil in the constant MD after being wound using a controlled WOT profile that varies the WOT depending on the diameter that is wound on the coil (for example, as in Figure 6).

The repeated use of numerical references in this descriptive report and drawings is intended to represent the same or analogous characteristics or elements of this description.

DETAILED DESCRIPTION

Reference will now be made in detail to the currently preferred embodiments of the present description, one or more of which are illustrated in the attached drawings and appendices. Each example is provided by way of explanation of the present description, it is not limited to the details of the examples. Indeed, it will become obvious to those skilled in the art that various modifications and variations can be made to the present description without abandoning the scope or spirit of the present description. For example, features illustrated or described as part of one embodiment, can be used in another embodiment to produce another embodiment. Thus, it is intended that the present description includes such modifications and variations within the scope of the appended claims and their equivalents.

Figure 1 schematically shows a wound coil 20 of continuous VFL elastomeric mat and the directions of the three main stresses over a section of the mat within the coil. Consequently, as shown in Figure 1, the arrows designated MD show the direction of the tension by winding (WOT), while the arrows designated ZD show the pressure between layers acting in the radial direction with respect to the coil.

Typically, in most blanket processing devices, the coils wrapped in blankets are wound in tension by means of a constant winding "WOT" (tension in the current winding layer, that is, the outermost layer of the wound coil). An exception could be the use of tension or tapered choke for film reels in order to reduce coil blockage. When the MD module and ZD module of a blanket material are very close to each other and the coil is wound in tension by means of constant winding, then the wound coil of that material exhibits a unique voltage characteristic stored in MD along the coil. In a conversion process, during the unwinding of the coil, the state of any given section of the blanket is different depending on the diametrical location where that section was stored on the coil.

In many processes that employ continuous webs that are unwound from a rolled coil, it is desirable to have as little variation as possible in the state of the web as the web is unwound so that the web status is essentially uniform if the web ends at the outside diameter of the coil, the inner diameter of the coil15 in or somewhere between the two extreme diameters of the coil. To obtain such a desired uniformity in the state of the mat, the physical properties of the wound coil can be manipulated according to the present description to provide a coil with tension stored in the MD along the substantially uniform coil. For a given material, the core and coiled coil configurations, the voltage state within the coiled coil is determined by WOT. Then, according to the present description, by manipulating the WOT to follow a compensated WOT profile as the mat material is wound on the coil, it was possible to obtain a substantially uniform MD tension on the resulting wound coil. As noted above, as a first step in this process, a computer model of the winder is used to determine the initial stress conditions on the MD within a wound coil of the continuous mat material as a function of the wound coil diameter, assuming a constant WOT in the blanket material as that blanket material is wound onto the coil. As noted above, this computer model of the winder is based on Hakiel's nonlinear model on winding coil voltages mentioned above, but modified to incorporate the new procedure that is described in this description and a suitable winder computer program is presented. here as Appendix A.

Required input values:

Properties of wound coil:

MD module, ZD module and Poisson ratio of the blanket material

Blanket thickness

Outside diameter of wound coil

Winding tension (WOT)

Core properties:

Core inner and outer diameter

Young's modulus, Poisson's ratio Example One:

For example, consider a material whose properties are listed below.

Blanket properties, wound coil:

MD Module = 25 Psi

Module ZD -> Ki = 0.1, K₂= 10 Psi (Pfeiffer form - determined in the

Hakiel)

Poisson's ratio = 0.03

Diameter of wound coil = 1.27 m (50 inches)

Rolled coil width = 15.24 cm (6 inches)

Winding voltage = 10 Psi

Core properties:

Core inner diameter = 22.86 cm (9 inches)

Core outside diameter = 25.4 cm (10 inches)

Core module = 100000 Psi

Core Poisson's ratio = 0.3

Consider a coil that has been wound in tension by means of constant winding (WOT) of 10 Psi of the blanket with properties listed above as shown in Figure 2. The tension profile along the coil exclusive of such coiled winding of this radial tension blanket material is shown in Figure 3, and the tension profile along the coil unique to such a coil wound from that tension blanket material in the MD is shown in Figure 4. A modified version of the Hakiel model can be used to generate a computer program for the winder that computes the voltages and the results that are graphically presented in Figures 3 and 4. The computer program presented in Appendix A is a modality of such a program computer of the winder that was used to generate the data presented in Figures 3 and 4. P Appendix B is an example of an Excel screenshot that has input values ​​and output values ​​(numbers and graphs) from the winder computer program that is shown in Appendix A. For each data point selected, the winder computer program generates a compensated WOT value predicted to obtain a voltage in the MD along the substantially uniform coil in the wound coil that has an outside diameter of 1.27 m (fifty inches) wound in a core with an outside diameter of 25.4 cm (ten inches).

These data points provide a compensated WOT profile as a function of the diameter of the rolled coil of blanket material. The compensated WOT profile can be inserted into software that converts the data points into a winder smoothdraw control program to obtain a tension in the MD along the substantially uniform coil in the blanket material that the winder is controlled in this way , will wind on the coil.

Since the desired property is the voltage in the MD along the coil, the 5 WOT needs to be controlled to make that voltage property in the MD substantially uniform. This can be done according to the present description using the “WOT Transposition” to correct the constant WOT winding profile in order to obtain a controlled WOT winding profile (also known as compensated) that can be used to wind the material in a hard coil that exhibits properties (including tension in the MD in the mat) that are substantially uniform throughout the coil.

The concept of “WOT transposition” was schematically explained in Figure 5. Since the voltage in the MD reduces with an increased diameter of a fully compressed coil, then a WOT profile that compensates for the reduction in the coil voltage at each diametrical location that such coil was wound in tension by means of constant winding “WOT”, it should produce a tension along the uniform coil in the wound coil. This is the self-styled compensated WOT profile that is required on the mat as the mat is wound on the spool to provide the wound spool with a tension on the MD along the substantially uniform spool and other mat properties.

Winding a coil of blanket material in a constant WOT, as shown in Figure 5 (a) will produce a radial tension profile shown in Figure 5 (b) for fully compressed coils. Since the WOT is the voltage at which the blanket enters the coil, it was concluded that the coil voltage cannot be greater than this constant value of the WOT. When wound in constant WOT as shown in Figure 5 (c), the voltage in the MD inside the coiled coil of blanket material will fall below the constant WOT value, and a graph of that voltage in the MD inside the coiled coil as a function of diametrical location inside the coil will display a format similar to the 'Nike®Swoosh®' profile. Thus, at each intermediate diametrical location within the coil, there is a reduction between the tension in the MD within the coiled coil and the constant WOT at which the blanket material was wound in the coil.

If this reduction (between the constant WOT shown in Figure 5 (a) and the voltage in the

MD on the wound coil shown in Figure 5 (c)) as shown in Figure 5 (d) is added to the constant value of WOT as shown in Figure 5 (e) at corresponding diametric locations, the radial pressure generated, as shown in Figure 5 (f), will be greater than the radial pressure generated at constant WOT value. Although the values ​​of radial pressure generated are higher, the tension in the MD along the coil is now substantially uniform, as shown in Figure 5 (g). Although the stresses in the MD are non-uniform very close to the nucleus, they are substantially uniform elsewhere. Furthermore, in terms of coil length, the yardage in the tension zone in the non-uniform MD very close to the core is responsible for less than about 2% of the total coil length. Thus, using the technique of the present description, the tension in the MD along the coil can be substantially uniform over about 98% of the total blanket length measured from the outside diameter of the coil wound inward towards the core of the wound coil. For this technique to work, it must be kept in mind that the coil should be a "hard" coil, that is, a coil completely compressed.

With reference to Example One, it is observed that in the outer diameter of the coil double 10, the voltage in the MD is equal to the value of the WOT, which in this case is 10 Psi. Elsewhere on the hard coil, the voltage on the MD inside the coiled hard coil does not exceed the WOT value. In this case, that value is 10 Psi.

Once a diametrical location is determined, the voltage in the MD is less than the WOT in an amount "Xd", where "X" corresponds to the difference between the WOT and the voltage in the MD, and "d" corresponds to the diametrical location. If this “Xd” reduction is added to the WOT as the corresponding coil diameters are being wound, then a new compensated WOT profile that varies as a function of the diameter (instead of being constant as in Figure 2) can be obtained . This new compensated WOT profile is shown in Figure 6.

The same computer program that implements the computer model of the winder is then used to calculate the stresses in a coil that has been wound using the compensated WOT profile that is shown in Figure 6. Figure 7 graphically shows these radial stresses calculated by the same computer program of the blanket winder inside the wound coil that could be created using the compensated WOT profile that is shown in Figure 6. The stresses in the MD inside the wound coil that could be created using the compensated WOT profile that is shown in Figure 6 are calculated by the same computer program as the winder, and these calculations are shown in Figure 8. It is observed that in each location diametrical, the radial stresses shown in Figure 7 are slightly higher than those shown in Figure 3, this is due to a higher total WOT.

However, the voltages in the MD shown in Figure 8 are nominally constant and substantially uniform across the coil as a result of using a controlled WOT (shown in Figure 6 for that particular modality).

This method according to the present description will work for blankets that have MD module and ZD module that are very close to each other.

For example, with reference to the fourth column on the left in the chart in the Appendix

B, the blanket with a diameter of 76.2 cm (30 inches) from the coil wound in a constant 10 psi WOT is provided by the winder computer program (shown in

Appendix A) to have an MD tension (stress) of 7.848 psi. This means that at this 76.2 cm (30 inch) diametrical location within the coiled coil of material there is an expected reduction of 2.152 psi (10 - 7,848) in the maximum 10 psi MD voltage that could be transmitted to the mat due to Constant 10 psi WOT be applied to wrap the blanket around the coil. To compensate for this 2.152 psi reduction in the coil's 76.2 cm (30 inch) diameter, the compensated WOT profile requires a 12,152 psi (10 + 2.152) WOT, which appears in the fifth column on the left of the graph in Appendix B under the title “Controlled WOT”. Using the same computer model as the winder (shown in Appendix A), the tension in the MD (stress) in the blanket in the diameter of 76.2 cm (30 po10 legacies) of the coil wound in the 12,152 psi compensated WOT is calculated for be 10.061 psi in the seventh column from the left in the graph in Appendix B. As can be seen from a check of the other entries in the seventh column on the left in the graph in Appendix B, the strain on the MD in the coil of material wound according to the compensated WOT profile is expected to be substantially uniform across the coil at about 10 psi.

Winding process control

When flexible low modulus materials are wound on a coil, it is common to operate the winder in “stretch control”, where the compensated WOT profile is converted into speed control based on a known relationship between the winder speed and the tension in the MD in the blanket. Stretch control (also known as speed control or activity control) works by controlling the speed of the winder and thereby controlling the tension in the MD in the blanket that penetrates the winding coil. The control system, which can typically include a programmable logic controller (PLC), can be programmed to control the winder in a stretch control mode. However, neither the speed (expressed in feet per minute) nor the stretch (expressed as%) is a direct measure of the blanket tension or WOT. To determine WOT, someone must find an accurate way to express the relationship between winder speed and WOT.

There are different methods that can be used to establish a relationship between stretch (or speed) and WOT. One method uses a load cell that directly measures the tension of the mat in the process of winding the mat in the bobbin. One could vary the stretch and observe the change in tension measured by the load cell and establish a relationship between the two. Another method calculates the stress on the mat by multiplying the deformation of the mat and the MD module of the mat. The deformation of the mat can be calculated based on the speed difference between the winder and the previous driven cylinder ([Vw - V1] / V1, where Vw is the speed of the winder and V1 is the speed of the cylinder before the winder).

While methods that use stretch control or speed control are now considered more desirable, it is also possible to employ methods that use tension control, torque control or throttle control. When the winding process works in “tension control”, then the tension in the mat is a known quantity, since a load cell that indicates the tension is already present in the process equipment. In this case, a relationship can be established between the unwinding motor current and the mat tension at various brake levels. The same procedure can also be followed by torque-controlled winders. The PLC control system software can be used to control the winding motor current as a function of the wound coil diameter using a set of distinct points from the compensated WOT profile and interpolation between these points to make the desired change in stretching as a function of the bobbin diameter.

Since the desired production of WOT that will generate tension in the MD along the substantially uniform coil (as shown in Figure 8, for example) is obtained as a function of the diameter of the coil as the blanket is wound on the coil, then the control system, which can typically include a programmable logic controller (PLC), can be programmed to control the winder (in stretch control) and unwinding brake (in tension control). Common control system software for this purpose is available from Rockwell, Siemens, and many others for such process line equipment. These programs use their own programming language to control the various devices in the winding process.

In the case of stretch control, the production of the WOT winding model is converted into stretch (or speed) based on the relationship established between stretch / speed and the WOT in the mat. A simple program can then be recorded using the control system software to control the speed of the winder as a function of the winding diameter using a set of distinct points from the production of the winding model and linearly interpolating between these points to perform the change in stretching as a function of the bobbin diameter as the bobbin is then wound. The conversion procedure is very similar for voltage control, however in the case of voltage control the unwinding motor current that is controlled as the coil is wound. Thus, a PLC can be used to control the winder as a function of the compensated WOT profile in a voltage control mode. For example, PLC control system software can be used to control the winding motor current as a function of the wound coil diameter using a set of distinct points from the compensated WOT profile and interpolation between those points to perform the desired change in extension as a function of the coil diameter.

In the case of strangulation control, the production of a winding model

WOT can be converted to the different choke loads that are required to obtain a target WOT for a given constant blanket tension. A general WOT equation that can be used in the absence of empirical measures of strangulation-induced tension can be expressed as follows. WOT = Tw + // N, where WOT = Winding Stress, Tw = Blanket Stress, μ = Dynamic Blanket Coefficient of Friction for Blanket, and N = strangulation load.

Measure of voltage uniformity in MD

Once two coils are wound - one wound using a controlled WOT, as determined above (Figure 6) and the other wound using a constant WOT (Figure 2) - it becomes necessary to develop a protocol to measure the tension in the blanket MD as a function of the coil diameter. Depending on the material and the requirements of the process, the voltage uniformity in the MD in a coil can be measured having a particular and predictable relationship with the measurement of several other parameters that are more easily, that is, directly, obtained by real measurement. Some of the ways include the following. The tension in the MD can be measured as the variation in length of each individual cut made in the mat during the unwinding process. The strain on the MD can also be measured by documenting the repeated length of a printed graph during the unwinding process. The stress in the MD can also be measured as the variation in deformation at the flow point of the mat at different diametrical locations during the unwinding process. The strain on the MD can also be measured by connecting electrical strain gauges to the mat at various diametral locations and documenting uniformity based on the uniformity of strain measurements obtained in this way. For example, the "flow deformation" along the coil was actually measured. In short, the sections (known as specimens) of the same length were cut from the mat in different diameters along the coil, loaded into a tensile tester and stretched to a fixed load. The substantial uniformity in deformation along the coil in a coil of a very low modulus laminate mat can be deduced from the "flow point deformation" during the unwinding process.

Flow deformation

The step-by-step procedure for measuring the “flow deformation” parameter shown in the Figures, can be summarized as follows: Mark two lines with 15.24 cm (6 inches) of separation along the circumference of the coil (ie , the marks are separated in the machine direction by 6 inches (15.24 cm) on the outside diameter. Then, cut a specimen that is 20.32 cm (8 inches16 inches) long by 7.62 cm (3 inches) wide (in the machine direction) from the material so that the two marked lines appear inside the body of proof. Then load the specimen into a tensile tester, using the two marked lines to ensure that the claws on the tester are 15.24 cm (6 inches) apart. Therefore, the specimen is held in the jaws so that the two lines end 15.24 cm (6 inches) apart between the jaws. The specimen is then stretched at a constant strain rate while the stress and strain are simultaneously recorded at a number of different points, which are represented on the curve shown below. The flow deformation is then recorded at the inflection point on the curve as shown in the figure below. This procedure is repeated throughout the coil, performing the same test on different diameters inside the coiled coil.

<img file="BRPI0807973B1_D0001.tif" />

<img file="BRPI0807973B1_D0002.tif" />

Also, the deformation in the MD stored along the coil was actually measured. The "deformation in the MD" is determined in a similar way to that described above, except that in the case of deformation in the MD, the specimen is observed for the amount of shrinkage. The specimens of the same length were cut from the mat in different diameters along the coil and observed for the amount of shrinkage. Based on the shrinkage, the deformation in the stored MD can be calculated as the ratio of the difference in length to the original specimen length.

Deformation in the MD

The step-by-step procedure for measuring the “deformation in MD” parameter shown in the Figures can be summarized as follows: Mark two lines with 15.24 cm (6 inches) of separation along the circumference of the coil in the outside diameter. Then, cut a specimen that is 20.32 cm (8 inches) long by 7.62 cm (3 inches) wide so that the two marked lines appear inside the specimen. Place the specimen on a flat surface and measure the retracted length (the distance between the two marked lines) immediately. The deformation in the MD that is stored in the coil is then calculated as the ratio of the difference between the original length and the retracted length to the original length and is expressed as a percentage (%) of the original length. This procedure is repeated throughout the coil, performing the same test on different diameters inside the coiled coil. The stretch profile is shown in Figure 9, and the results in terms of de5 formation in the MD in each blanket are shown in Figure 10a. Note that each data point in each Figure 10a - and 11 ae represents an average of three individual measures and the variability in the data can be expressed using a parameter called Coefficient of variance, which is explained below çn% Cv = ~ - xlOO

Average where% Cv is the Coefficient of variance and SD is the Standard Deviation. Thus, the higher the% Cv value, the greater the variability in the data. The stretch profile shown in Figure 9 was obtained by converting the stress values ​​to stretch based on a relationship established between the stretch and tension, as described in the previous section. So, as shown in Figure 9 for a coil of a first VFL material, the stretch of the winder changes from about 39% when the blanket is wrapped around the core of the bobbin to about 43% when the blanket is wound approximately in the middle of the wound bobbin and then returns to about 38% when winding the blanket on the outside diameter of the coil wound in a relatively smooth controlled manner determined by the data points generated from the computer program of the winder. It is observed that uniformity is measured in terms of deformation.

As predicted and shown by the graph of data points represented by a square in Figure 10a, the coil that was wound using the controlled WOT has a relatively constant MD deformation in each diameter inside the coil. As shown by the line representing the data points represented by a diamond in Figure 10a, the coil that was wound using the constant WOT with the same first material

VFL has a deformation in the MD widely varied depending on the location on the coil that the measurement is taken on the blanket wrapped around the coil. This greater variation in the coil that was wound using the constant WOT with the same first VFL material is confirmed by the alternative flow deformation measures as a function of the coil diameter shown in Figure 10b. Furthermore, as shown in Figures 10c and 10d, the greater variation of the respective deformation measures in the MD and flow deformation measures (the data points represented by a rhombus) becomes even more evident when the measures are represented as a function of the distance along the length of the coil from the end of the coil in the core to the free end of the material.

As seen in Figure 10a, the strain measurements on the MD of the coil wound in constant WOT exhibit a 15.5 percent deviation around the mean, while the strain measurements on the MD of the wound coil in the controlled WOT exhibit a deviation of only 5 , 6 percent around the average, which is a uniformity greater than about 64% (1-5.6 / 15.5) with the same blanket material when wrapped in the controlled WOT according to the present description. This same result of substantial uniformity along the coil is also obtained as shown in Figure 10b by the flow deformation data (data points represented by a square) which are represented as a function of the diametrical position on the coil with the same first VFL material . In addition, as shown in Figures 10c and 10d, the substantial uniformity of the respective strain measurements in the MD and flow strain measurements (the data points represented by a square) becomes even more evident when the measurements are represented as a function of the distance along the length of the coil from the end of the coil in the core to the free end of the material. As shown in Figures 10a (64%), 10b (49%), 10c (64%) and 10d (49%), there is an increase of at least about 50% in uniformity in each case.

Figures 11a, 11b, 11ce11d show graphically several comparisons between the measured properties of a blanket of a second VFL material when it is in constant WOT and in the controlled WOT advised by the present description. As can be seen when comparing relatively lower flow strain data in Figure 11b with the data in Figure 10b, the second VFL material is less common than the first VFL material. And the degree of uniformity is always much greater in the coil that is wound in the controlled WOT according to the present description.

Figure 11b, for example, allows a graphical comparison of the flow deformation in the measured MD (the data points represented by a square) of a wound coil using a controlled WOT profile (depending on the diameter that is wound on the coil, for example , as in Figure 6) and the flow deformation in the MD measured in the mat (the data points represented by a diamond) inside a coil (upper curve) wound using a constant WOT (as in Figure 2) regardless of the diameter that is wound on the coil. As predicted, and shown by the data represented by a square in Figure 11b, the coil that was wound using the controlled WOT 30 has a relatively constant MD flow strain measurement at each diameter within the coil of the second VFL material. As shown by the data points represented by a square in Figure 11b, the coil that was wound up using the constant WOT has a flow deformation measure in the MD widely varied depending on the location on the coil that the measurement was taken on the second material mat

VFL wound on the coil. This greater variation in the coil that was wound using the constant WOT with the same first VFL material is confirmed by the alternative strain measurements in the MD as a function of the coil diameter shown in Figure 11a. In addition, as shown in Figures 11c and 11d, the greater variation of the respective strain measurements in the MD and flow strain measurements (the data points represented by a rhombus) is still evident when the measurements are represented as a function the distance along the length of the coil from the end of the coil 5 in the core to the free end of the material.

As seen in Figure 11a, the strain measurements in the MD of the coil of the second VFL material wound in constant WOT exhibit a 13.9 percent deviation around the mean, while the strain measurements in the MD of the wound coil in the controlled WOT exhibit a deviation of only 4 percent around the average, which is a uniformity greater than about 71% (1-4 / 13.9) with the same blanket material when wrapped in the controlled WOT according to the present description. This same result of substantial uniformity along the coil is also obtained as shown in Figure 11b by the flow deformation data (the data points represented by a square) which are represented as a function of the diametrical position on the coil with that same second material VFL. In addition, as shown in Figures 11c and 11 d, the substantial uniformity of the respective strain measurements in the MD and flow strain measurements (the data points represented by a square) becomes more evident when the measurements are represented as a function of the distance along the length of the coil from the end of the coil in the core to the free end of the material. As shown in Figures 11a (71%), 11b (59%), 11c (71%) and 11d (59%), there is at least an increase of at least about 50% in uniformity in each case.

As evident from the data presented in Figures 10a, 10b, 10c, 10d, 11a, 11b, 11c and 11 d, the variability along the tension coil in the MD of the coil of rolled blanket material according to the WOT profile compensated is reduced by about 40% to about 70% with respect to the variability along the tension coil in the MD of a coil of the same blanket material and the same diameter wound in constant WOT.

Figure 12 shows schematically in the form of a flow chart, the steps that can be taken to practice a modality of the method of the present description that produces a tension coil in the MD substantially constant after being wound using a controlled WOT profile that varies the WOT depending on the diameter that is wound on the coil (for example, as in Figure 6). The present method is particularly useful for extensible and / or elastic blankets (for example, films, yarns, non-woven materials and laminates of one or more of the above) such as the MD elastomeric laminates described in U.S. Patent No. 5,385,775 with Wright, US Patent Application Publication No.

2002/0104608 with Welch, et al., And US Patent Application Publication No.

2005/0170729 with Stadelman, et al., Each of which is incorporated here in its entirety for all purposes as a reference. Materials that exhibit the following behavior will benefit from the winding technique of the present description:

Any blanket material that has a Machine Steering Module that is close to the Radial Module or

Any materials that have a “Nike®-Swoosh®” profile along the coil as measured by the Stress or Strain in the MD or some other parallel measure

Typically, the following materials are among those that are included in the above categories: non-woven, non-woven laminates, machine-oriented (MD) elastomeric (stretched on MD), elastomeric laminates on MD, films, film laminates and highly aerated fabrics where the MD and ZD Module is close to the same value. Although at least one currently preferred embodiment of the present description is described using specific terms, such description is for illustrative purposes only, and it should be understood that changes and variations can be made without departing from the spirit or scope of the following claims.

APPENDIX A

This computer program was written in Visual Basic Application (VBA) code within an Excel document.

Option Explicit

Sub Winding_Model_For_Uniform_Properties ()

Dim Et As Double, Pr As Double

Dim K1 As Double, K2 As Double

Dim Ec As Double, NL As Integer 3

Dim h As Double, Tw As Double

Dim Rmin As Double, Rmax As Double

Dim Rc As Double, Prc As Double

Dim i As Integer, layer As Integer

Dim k As Integer, m As Double

Et = Range (Emd): Pr = Range (pnr)

K1 = Range (kone): K2 = Range (ktwo) h = Range (h): Tw = Range (tw): NL = Range (nl)

Rmin = Range (COD) / 2: Rmax = Range (WOD) / 2 Rc = Range (CID) / 2: Prc = Range (pnrcore)

Ec = Range (ec) * ((Rmin ^Λ 2 - Rc 2) / (Rmin ^Λ 2 + Rc ^Λ 2 -Prc * (Rmin ^Λ 2 - Rc ^Λ 2)))

ReDim Rp (NL + 1) As Double, Ts (NL + 1) As Double

ReDim r (NL + 1) As Double, Er (NL + 1) As Double

ReDim dp (NL + 1) As Double, dt (NL + 1) As Double

ReDim a (NL + 1) As Double, b (NL + 1) As Double ReDim c (NL + 1) As Double, d (NL + 1) As Double ReDim bd (NL + 1) As Double, dd (NL + 1) As Double ReDim Twc (NL + 1) As Double

Range (E5: M20000) .Select

Selection.ClearContents Range (E5) .Select With Application

Calculation = xlCalculationAutomatic 10 End With

For i = 1 To NL + 1

Rp (i) = 0: Ts (i) = 0: r (i) = 0: Er (i) = 0 dp (i) = 0: dt (i) = 0: a (i) = 0: b ( i) = 0 c (i) = 0: d (i) = 0: bd (i) = 0: dd (i) = 0

Next i

For i = 1 To NL + 1 r (i) = Rmin + (i - 1) * h Next i 'Radial layer pressure 1 dp (1) = Tw / r (1) * h

Rp (1) = Rp (1) + dp (1)

Er (1) = K2 * (K1 + Rp (1)) dt (1) = Tw

Ts (1) = Ts (1) + dt (1) 'Radial pressure of layer 2 and 1 dp (2) = Tw / r (2) * h Rp (2) = dp (2)

Er (2) = K2 * (K1 + Rp (2)) dt (2) = Tw

Ts (2) = Ts (2) + dt (2) dp (1) = (dp (2) * r (1) / h) / (Et / Ec-1 + Pr + r (1) / h)

Rp (1) = Rp (1) + dp (1)

Er (1) = K2 * (K1 + Rp (1)) dt (1) = -dp (1) * (Et / Ec + Pr)

Ts (1) = Ts (1) + dt (1)

For layer = 3 To NL + 1

Range (A24) = Performing Constant WOT Calculations' set up tridiagonal matrix a (layer) = 0: b (layer) = 1 c (layer) = 0: d (layer) = Tw * h / r (layer)

For i = 2 for layer -1 a (i) = 1 + (3 * h) / (2 * r (i)) b (i) _ (h 2 / r (i) ^Λ 2) * (1 -Et / Er (i)) - 2 c (i) = 1 - (3 * h) / (2 * r (i)) d (i) = 0

Next ia (1) = 1: b (1) = - (EVEc-1 + Pr + r (1) / h) * h / r (1) c (1) = 0: d (1) = 0 'solve the tridiagonal matrix using Thomas' Forward elimination algorithm bd (1) = b (1): dd (1) = 0 For k = 2 For layer m = c (k) / bd (k-1) bd (k) = b (k) -m * a (k-1) dd (k) = d (k) -m * dd (k-1)

Next k 'Backward Substitution layer) = dd (layer) / bd (layer)

For k = layer -1 To 1 Step -1 dp (k) = (dd (k) - a (k) * dp (k + 1)) / bd (k)

Next k dt (1) = -dp (1) * (Et / Ec + Pr) dt (layer) = Tw

For k = 2 For layer -1 dt (k) = -dp (k) - r (k) * (dp (k + 1) - dp (k -1)) / (2 * h)

Next k

For k = 1 For layer

Rp (k) = Rp (k) + dp (k)

Er (k) = K2 * (K1 + Rp (k))

Ts (k) = Ts (k) + dt (k)

Next k

If layer / 10 = lnt (layer / 10) Then

Range (B23) = layer

End If Next layer

For i = 1 To NL + 1 Cells (i + 4, 5) = 2 * r (i)

Cells (i + 4, 6) = Tw Cells (i + 4, 7) = Rp (i)

Cells (i + 4, 8) = Ts (i)

Next i

For i = 1 To NL + 1 Twc (i) = Tw + Tw - Ts (i)

Next i 'Calculation of uniform properties begins in the following lines

For i = 1 For NL + 1 Rp (i) = 0: Ts (i) = 0: r (i) = 0: Er (i) = 0 dp (i) = 0: dt (i) = 0: a (i) = 0: b (i) = 0 c (i) = 0: d (i) = 0: bd (i) = 0: dd (i) = 0

Nexti

For i = 1 To NL + 1 r (i) = Rmin + (i-1) * h Next i 'Radial pressure of layer 1 dp (1) = Twc (1) / r (1) * h

Rp (1) = Rp (1) + dp (1)

Er (1) = K2 * (K1 + Rp (1)) dt (1) = Tw

Ts (1) = Ts (1) + dt (1) 'Radial pressure of layer 2 and 1 dp (2) = Twc (2) / r (2) * h Rp (2) = dp (2)

Er (2) = K2 * (K1 + Rp (2)) dt (2) = Twc (2)

Ts (2) = Ts (2) + dt (2) dp (1) = (dp (2) * r (1) / h) / (Et / Ec-1 + Pr + r (1) / h)

Rp (1) = Rp (1) + dp (1)

Er (1) = K2 * (K1 + Rp (1)) dt (1) _-dp (1) * (Et / Ec + Pr)

Ts (1) = Ts (1) + dt (1)

For layer = 3 To NL + 1

Range (A24) = 'Perform Controlled WOT Calculations'

Adjust tridiagonal matrix a (layer) = 0: b (layer) = 1 c (layer) = 0: d (layer) = Twc (layer) * h / r (layer)

For i = 2 For layer -1 a (i) = 1+ (3 * h) / (2 * r (i)) b (i) _ (h ^Λ 2 / r (i) ^Λ 2) * (1 - Et / Er (i)) - 2 c (i) = 1 - (3 * h) / (2 * r (í)) d (i) = 0 Next ia (1) = 1: b (1) = - (Et / Ec-1 + Pr + r (1) / h) * h / r (1) c (1) = 0: d (1) = 0 'solve three-dimensional matrix using Thomas algorithm Forward elimination bd (1) = b (1): dd (1) = 0

For k = 2 For layer m = c (k) / bd (k -1) bd (k) = b (k) -m * a (k-1) dd (k) = d (k) - m * dd (k -1)

Next k 'Backward Substitution dp (layer) = dd (layer) / bd (layer)

For k = layer -1 For 1 Step -1 dp (k) = (dd (k) - a (k) * dp (k + 1)) / bd (k)

Next k dt (1) = -dp (1) * (Et / Ec + Pr) dt (layer) = Twc (layer)

For k = 2 For camda 1 dt (k) = -dp (k) - r (k) * (dp (k + 1) - dp (k -1)) / (2 * h)

Next k

For k = 1 For layer

Rp (k) = Rp (k) + dp (k)

Er (k) = K2 * (K1 + Rp (k))

Ts (k) = Ts (k) + dt (k)

Next k

If layer / 10 = lnt (layer / 10) Then

Range (B23) = layer What if

Next layer Ts (1) = Ts (2)

Parai = 1 ParaNL + 1 Cells (i + 4, 9) = Twc (i)

Cells (i + 4, 10) = Rp (i)

Cells (i + 4, 11) = Ts (i)

Cells (i + 4, 12) = Tw * 0.1 + 100 Cells (i + 4, 13) = Twc (i) * 0.1 + 100 Next i

Range (A24) = Finished Calculations End Sub