MXPA97007643A - A covered roller and a method to manufacture my - Google Patents

Abstract

Coated rolls having reduced residual stresses are described by the inclusion of one or more intermediate compressive layers, and the method for manufacturing, in one embodiment, the intermediate compressive layer comprises a three-dimensional fabric that is preferably filled with a thermal setting resin system which is cured at a lower temperature wing of the cover, in a second embodiment, the precise amount of shrinkage in the roll is predetermined to a sufficiently high degree of accuracy, so that a thickness for the appropriate fabric layer can be used to compensate the amount of shrinkage, thereby eliminating the need for filling, in a third embodiment, the compressive layer is comprised of a meltable material, wherein said material melts at the curing temperatures, the resulting cavity is then filled with a setting resin thermal, the problems caused by chemical and thermal shrinkage are further reduced by r means of a method consisting in the application of a polymeric cover layer on one or more intermediate compressive layers, curing at an elevated temperature, and letting the cover contract during its cure or hardening.

Description

A COVERED ROLLER AND A METHOD TO MANUFACTURE THE SAME FIELD OF THE INVENTION The field of this invention is that of covered tires for industrial applications, and more particularly, of rollers with relatively hard covers and methods for rabbiting said rolls.

BACKGROUND OF THE INVENTION Coated rollers are used mdust palment e in demanding media where they are subjected to dynamic and high temperatures. For example, in a typical paper mill, a large number of rollers are used, not only to transport the web sheet that became paper, but also to convert the web itself into finished paper. These rollers are precision elements of the system that are precisely balanced with surfaces that must be maintained in specific configurations. A roller type that is particularly subject to high dynamic rates, is a calender roll, and calendering is used to improve the uniformity, brightness, print quality and thickness of the paper. The calendering section of a paper machine is a section in which the rollers themselves contribute to the manufacture or treatment of the paper and not only to the transportation of the belt to the machine. To function properly, the calender rolls must have extremely hard surfaces. For example, the calender rolls are typically covered with a thermal-set resin having a hardness O on the scale of 84-95 and an elastic modulus on the scale of 1,000-10,000 MPa. More commonly, opox ress are used to cover the calender islets because the epoxy resins form extremely hard surfaces. The thermal setting resins, such as epoxy resins with suitable characteristics to form the surfaces of calender rolls, are cured at relatively high temperatures. Currently, these resins are cured at temperatures on the scale of 100 to 150 ° C. It is well known that the higher the cure temperature for heat resistant resin systems, the higher the thermal resistance of the resulting coating. In addition, the modern demands of the paper mill require rollers, particularly calender rolls, with superior thermal resistances. In this way, it would be convenient to produce covers for these rollers that can be cured at 150-200 ° C. However, before the present invention, curing at these high temperatures caused so much effort that the cover tended to crack, becoming unusable. A discussion of the physicochemistry of this roller cover can be found in a document entitled "The Role Of Cornposite Role l Covers In Soft And Supercalenden g," 3.. Paasonen, presented at the 46th Annual Atip Congress, Grenoble Atria Uorld Trade Center Europole, 20-22 October 1993, the teachings of which are incorporated herein by reference. In fact, a major challenge for the roller cover manufacturer is to develop roller bearings that can withstand the high residual stresses caused during manufacturing. Problems caused by residual stresses are more signiicant in the harder compounds (higher stiffness) and often cause cracking, rolling, and edging. Residual stresses not only promote undesirable cracking and / or the tendency to lift edges of the roof, but often cause premature local failure or shorter life cycles than desired. This is especially true for high performance hard roller polymer covers, where the basic approach has been to tolerate a level of residual stress production that is still acceptable from a product performance standpoint. Therefore, there is a need to develop methods of roller cover construction that reduce residual stresses in the product. The consideration of residual stresses is especially critical during the manufacture of the roller cover. In particularCare must be given to the heating and curing procedures, since these conditions are the most significant factors in the development of these efforts. Residual stresses are developed in polymer-based coatings as a result of the uneven thermal shrinkage properties between the shell materials and the core materials and their chemical contraction. The polymers, shell material, typically have a coefficient of thermal expansion that is of an order of magnitude greater than that of steel, core material. A suggestion to decrease the efforts caused by the covered roller treatment is to produce a cover as a finished product and a L5 cover completely cured with a core structure. This can be achieved by reviewing a mold with a cover (covered IOI), demoulding and attaching the cover to a core structure at a temperature level lower than the cure temperature of the cover, or by casting the cover or separately and joining it to a metal core at a temperature lower than the casting temperature. In this way, the thermal stresses that can occur between the cover and the core derived from the cooling of the cover from the curing temperature would be reduced. 5 Although adhesives are available, some adhesives exhibit poor bond strengths when the roller is subjected to industrial applications. In general, adhesives are required that cure at high temperatures for high temperature performance. However, co-operating the core at high temperature bonding conditions results in avoided efforts to produce the cover separately. In addition, manufacturing costs would increase with the need to have to first produce the cover as a separate cylindrical structure and then fit over a roller core at a lower treatment temperature than that required to treat the cover. of casting requires that an open cavity be formed between the cover and the core of the roller, which requires multiple treatment steps and the use of internal mandrels. Even if the cover is manufactured separately by a centrifugal casting method, additional costs and steps are required for an external mold. Another possible solution is to develop a roofing material that has a thermal contraction as close to that of the metal core as possible. Although mixed structures can be developed with coefficients of expansion designed to match those of the metallic core, these methods are expensive and may not produce the desired response to certain industrial applications. Therefore, there is a need to develop methods to reduce the levels of residual stress in current production materials.

BRIEF DESCRIPTION OF THE INVENTION According to the present invention, the problems caused by chemical and thermal shrinkage of hard roller covers are reduced by the inclusion of at least one intermediate compressive layer between the core of the roller and the outer cover, or top cover. This compressive layer is sufficiently rigid to allow the cover to be applied to the roller, while at the same time being compressible enough to deform and absorb the stresses that occur- > n conforming The cover shrinks during your treatment. In accordance with the present invention, the problems caused by chemical and thermal shrinkage are further reduced by a method consisting of applying a poly-clad cover layer on an intermediate compressive layer, curing at an elevated temperature, and allowing the cover to contract. during cure not hardening. In one embodiment of the present invention, the compression layer is filled with a filling material after the cover is completely treated. Therefore, it is an object of the present invention to provide a roller with a very hard poly-covered shell on a roll metal core. Another object of this invention is to provide covers for industrial rolls that have a high degree of flexibility and high resistance to the stresses that cause deformation. Another object of this invention is to provide rollers with hard polymeric covers for industrial applications that are less expensive than manufacture that existing rollers. Another object of this invention is to provide covers for industrial rollers that reduce the transfer of friction heat from one layer to the next. Another object of this invention is to provide covers for industrial rollers that last for a long time. Another object of this invention is to provide covers for industrial rollers that minimize or eliminate rotational slippage between the cover and the roller. Another object of this invention is to reduce the problems caused by chemical and thermal shrinkage that occur during the manufacture of a covered roller. Another object of this invention is to reduce the problems caused by residual stresses that occur during the manufacture of the covered roller. Another object of this invention is to provide an intermediate compressive layer between the metal roller and the outer shell, or upper cuviert, to absorb the efforts made by the cover on the metal roller. Another object of the invention is to provide an intermediate compressive layer that is sufficiently rigid to allow the cover to be applied to the roller while at the same time it is understandable and understandable to absorb the stresses that occur as the cover contracts. during the treatment. Another object of this invention is to fill the compressive layer with a filling material after the cover has been completely treated. Another object of this invention is to provide a covered roller having a structure of multiple layers of polymer or polymer blends, wherein one or more of the intermediate layers comprises a compressive layer. Another object of this invention is to provide an improved coated calender roller and a method for manufacturing said rod Lo.

BRIEF DESCRIPTION OF THE DRAWINGS Figure L is a cross-sectional view of a prior art roller having a multi-layer cover and showing diagramatically the thermal and residual stresses within the cover facing the roller core; Figure 2 is a cross-sectional view of the covered roller of the present invention having an intermediate compressive layer and showing diagramatic flesh as the thermal and residual stresses are absorbed within the shell by an intermediate compressive layer; Fig. 3 is a cross-sectional view of the covered roller of the present invention having an intermediate compressive layer -ipLi aa on a roller core having a base layer, and showing diagramatics and meat as they are absorbed the thermal and vertical stresses of the cubicle by means of a medium compressive layer; Figure 4 is a perspective view of the process of operation in accordance with the present invention, in which an upper cover is applied as a fabric impregnated with resin in layers; Figure 5 is a sectional view of the manufacturing process according to the present invention in which a top cover is cast into an external mold assembly; The Fig. 5 is a perspective view of separate parts of a metal roll core base and an extender assembly used to aid in the manufacture of rolls in accordance with the present invention; in perspective of an extender assembly paired with the surface of a roller core metal core in accordance with the present invention; Figure 8 is a sectional view taken along line 8-8 of Figure 7 of the present invention; covered roller of the present invention also showing the lower drilling sites which are located within the region defined by the surface of the extendable assembly i.out.Figure 9 is a partially sectioned view of a raised roller manufactured In accordance with the present invention, Figure 10 is a side view of an idimensional compressive separating fabric that can be used in the production of the present invention; n perspective of a sheet having a plurality of projections that define a plane in space; and Figure 12 is a quarter section of a finished covered roller manufactured in accordance with the present invention, showing a covered roller having an upper cover with a beveled edge and an intermediate separating fabric layer filled with a resin.

DESCRIPTION OF THE PREFERRED MODE At the beginning, the covered roller and the process for manufacturing the covered roller are described in their broader general aspects, with a more detailed description below. High performance coated rollers with reduced residual stresses are manufactured by means of a method of applying a poly-coated layer on an intermediate compressive layer. The purpose of the intermediate compressive layer is to absorb the thermal shocks and changes in chemical voLurne created during the open ion process. Referring now to the drawings, Figure 1 shows a covered roller L of the prior art. The arrows identified by the letter P on Ja F uia 1 indicate how the residual stresses and thermal shocks within the cover 2 are directed to the metal core of the roller 3. Although not indicated by the arrows in the Figure 1, recurrent stresses and thermal impacts also occur in other directions of the rodil, such as axially and radially. Finally, these internal stresses lead to premature cracking of the roller. Figure 2 shows an embodiment of the present invention wherein a covered roller 10 has a roller cover 11 applied over an intermediate compressive layer 12 and a metal core 13 base. The arrows idenified by the letter P in Figure 2 indicate As the intermediate compression layer 12 perrní te a The upper cover or roller cover 11 shrink in the direction shown during the hardening and cooling after heat treatment of this layer. Although not indicated by the arrows in the Figure 2, the intermediate compression layer 12 also allows the absorption of contraction and shocks in other directions within the roller, such as axially and radially. As will be apparent to the person skilled in the art, the compressive layer can be applied to a variety of bases of 1 roll, in addition to a metal core core of rod LLo. Specifically, the core of the roll 13 should have a resinous base layer 1 'formed around it, as shown in Figure 3. Furthermore, it will be readily understood that the metallic core 5 of the roll 13 shown in FIG. It can be laced with other suitable roller bases such as polymer roller bases or other mixed roller bases. However, when the roller base is a metallic core, it is typically a conventional metallic core made JO iron or steel. In an embodiment of the present invention, which includes a secondary treatment phase, the intermediate compression layer 12 comprises a three-dimensional separating fiber which, in the final stages after the production of the The upper cover, preferably, is formed with a water-tempering resin-forming system, which is cured at a temperature lower than that of the cover 11. However, the intermediate compression layer 12 does not have to be filled. In a modality, an important quantity, the quantity The precise shrinkage in the roll can be predetermined with sufficient accuracy, so that a thickness can be used for the appropriate intermediate layer of fabric to compensate for the amount of this shrinkage, and thus eliminate the need for padding. : > In another important embodiment of the present invention, the intermediate compressive layer is comprised of a wax or other meltable material, in fact, the wax or other meltable substance may be applied to the core 13 in the same manner as the resi to, e to is, through a mouthpiece. After a top cover or top is applied over the wax, the wax can be removed by melting, and the resulting swatch layer can be filled using conventional pressure casting methods., Fn the manufacture of a roll with ad with an important modality and with additional reference < -i Figure 2, a compression layer 12 is applied to a metal roller L3. Then, a cover material 11 is placed on the compressive layer, and the cover material is completely cured. During the curing process, the residual stresses are absorbed by means of the compressive layer 12 and do not cause the roller to crack. After the top cover Ll has been allowed to cure, the compression layer 12 is filled with a polymer that is cured at a lower temperature than that of the cover or the top cover-11, thus providing resistance to the root 1 lo and reducing the likelihood of cracking the roller cover Ll. In the embodiments of the present invention which comprise a magnetic separating fabric as an intermediate compressive layer, the fabric is laid on a suitable roll base with an adhesive cement. After curing, the surface of the separating fabric layer is covered with a ream and baked to form an intermediate compressive layer.

I 'i After curing - this resin cover surface surrounding the intermediate compressive layer, the cover layer is applied. Figure 4 illustrates in general terms how the cover can be applied from a resin-impregnated fabric roll on the rotating shaft. Another way to cover the roll is to cast the cover as shown in Figure 5, where a metal mold 20 is fitted over the roll after applying the intermediate layer 12. Afterwards, the cover is cured allowing the chemical changes and of resulting tempera The cover on the layer of separated fabric tridimen ional. To facilitate the filling of the compressive layer, Figure 6 shows how an extender cap assembly 20 is placed on each end of the metal core base of the roller. The extender cap assembly comprises a substantially circular plate 21 and a cylindrical section 22. Preferably, the plate 21 is made of wood and the cylindrical section is made of the same material as the base of the roller core 23. However, other suitable spreader cap assemblies, entirely different from wood or other similar materials, can be made, and may include other configurations, such as annular rings, annular rings with a screwed top plate or other cap configurations, including shoulder plates integral with the ring, and equivalents thereof. The figure ? is a perspective and cut-away view of the extendable lid assembly 20 in position on one end of the base of the metallic core of the roller 23 before the application of any layer, and as the outer surface of the section cylindrical 22 equals the circumference of the metal core base of the roller 23. After the cover 11 is applied and cured, drilling holes can be made in the region of the extension lids. Figure 8 shows a sectional view of the covered roller 30 of the present invention prior to the injection of material, filled in the intermediate compressive layer 32. The perforating holes 33 and 34 extend through the upper cover 31 and the material of the intermediate compressive layer 32, and are to be used as a conduit for filling the intermediate layer 32. The stitch lines 49 in Figure 8 and Figure 9 also show how the perforation holes are located within the region of the paver cover covered assembly comprising annular ring-36 and cylindrical section 35. As a final step of the process, the intermediate layer, now compressed, is filled with a system to form a thermal setting polymer. Figure 9 shows how this is achieved by lifting the roller on its lower end so that it is tilted or set at an angle on the scale of approximately 5-90 ° with respect to the horizontal. Then, the thermal setting ream forming system can be pumped under pressure into the intermediate compressive layer until the resin flows out of the upper faucets or taps. With reference to Figure 8, this is achieved by placing joints 38 and 39 on each end of the roller. Preferred reading, The joint is made of a wood similar to that of p. 21 described herein. The thermal setting ream forming system is pumped into the through hole 34 until the thermal setting resin forming system comes out of the valve 40 located in the through hole 33. Then, the valve 40 is closed and the SLsterna Continuous thermal setting resin former is pumped into the through hole 34 until it emerges from the valve 41 located at the top of the roller. At this point, the intermediate compression layer is completely filled. All that remains to complete the roller is to cut the extenders portions of the roller. After injection of the filling material into the intermediate compression layer 31, and curing of the filling material, the coated extender cap assembly can be removed from the rest of the roller, for example by cutting into the base of the metal core 37 in the proximity of dotted lines 49 indicated in Figure 8. In this way, the finished product is a covered roller that lacks any drilling hole. The manufacture of a roller covered with the aforementioned spreader cap assemblies serves to ensure that the intermediate layer of the finished roll is completely filled with material. Figure 10 shows how the comprehensive layer can be, for example, a layer of ridging separating fabric 50! having cross-linked support fibers 51 interwoven between an upper fibrous layer 52 and an inner fibrous layer 53. Examples of other suitable trimensional fabrics are described in U.S. Patent No. 5,052,440 issued to U. Givens, the teachings and description of which are incorporated herein by reference. Figure 11 shows another example of a suitable intermediate compressive layer which is a three-dimensional sheet having a single surface and a plurality of projections, wherein the projections extend from the surface to define a flat surface limit. As will be apparent to the person skilled in the art, the sheet can have a variety of projections including tapered, conical, hemispherical and the like. In addition, the bidirectional pattern or distribution of these projections may vary to include substantially checkerboard patterns, triangular patterns, and other configurations, depending on the method of roll manufacture. As will be apparent to the person skilled in the art, more than one compressive layer can be used if the design of the roller so indicates. The compression layer is preferably formed of a fabric, although other materials are suitable. It is readily apparent to one skilled in the art that different types of three-dimensional separator materials can be used as a compressive layer, including, but not limited to: three-dimensional textile separating fabrics; woven fabrics impregnated with res as; Ridimensional sheets made of fiberglass, polyester, vinyl ester or epox cas; and combinations and equivalents thereof. Typically, it is convenient to use a material pair-to the compressive layer that is flexible enough to be wound; sufficiently elastic to be compressed; stiff enough to hold a cover; and / or, sufficiently porous so that it can be filled with a suitable filter. It should be noted that the compressive layer has a remarkable thickness, usually of the order of 2 to 15 millimeters, with 4 rnrn being preferred, and should not be confused with woven or non-woven sheet materials which can be applied during the manufacture of coated rollers with one or more layers. It is important that the compression layer be filled with a material that forms a mixed part of the roller and can be compatible with the cover material. As explained in detail below, the filler material is usually a system of resins from the resin system used to form the cover, but which is cured at a lower temperature than the cover. An important aspect of the present invention is that the compressive layer remains unfilled with any resin formed material until after the covered material of the covered roller has been completely cured. When the compressive layer is formed of a fabric, the fabric is composed of a suitable material, preferably a 1 ') synthetic material such as a polyester, DACRON, or other synthetic material, such as nyJon. The prefended is a "Text Lie Spac ng Fabpc", which can be purchased from Muller Texti l GmbH, Postfach 31 40 D-5276 Wi hl ~ I) r abenderhohe, Germany, the details of which are provided in a catalog that displays the product number 5556, incorporated herein as a reference. Other separator fabric materials suitable for use include 3D-1KX, from MAYSKR GMBH & CO., L derberg, Post fach 1362, Germany, and a fiberglass product from PARApEAfl Industries, Hoogei dsest raat 49, 5700 AC Helrnond, Hol nda. The rollers according to the present invention can be used systems that produce two different polymers by curing. The shell-forming polymer is preferably a thermal setting resin and can be any polymer commonly used in the art, and does not form part of this invention. More usually, an epoxy resin is used to pair the top cover, such as an epoxy resin based on diglycidyl ether of bis phenol A, known commercially as DER 331 from Dow Chemical Co. This can be cured on a temperature scale of 130-150 ° C with an aromatic amine, such as dietiientoluend Lamina (DETDA 80) of Lonza Ag, Switzerland. As another example, the cover can be made of a Novoiac resin system modified with cyanate ester, provided by Allied Signal Inc., E.U.A. Preferably, the intermediate layer is filled with a thermal setting forming system which cures a temperature lower than that of the polymer system used for the upper cover, the intermediate layer may be filled with a resin. Although the filling material for the integumented layer is preferably a thermal setting material, a thermoplastic material may be employed. With the top cover, the preferred epoxy resin is based on di-glycidyl ether of bisphenol A, known commercially as DF.R 331 from Dow Chemical Co., but is cured on a temperature scale of Q-9 °. C with a suitable aliphatic amine, such as Jeffamine T-403, provided by Texaco Chemical Co., USA, In an exemplary embodiment, the teat layer is filled with a thermal setting polymer under conditions such that the development of residual stresses greater than those desired in the shell and also in the same separating fabric layer can be prevented. As an additional aid in the reduction of residual stresses, these thermal setting systems can be used for the compressive layer, which have combined properties of thermal shrinkage and properly designed curing. For base systems that require high temperature resistance, thermal setting systems designed so that the temperature of the glass transition in the base can be adjusted to the required level can be used. The invention is also illustrated by the following non-limiting example.

Although the present invention is applied to the originally manufactured rolls that have never been covered (0 I1), for use in mills, the present example is directed to a roller of a calender which has been removed from a paper mill with the purpose of being covered with a hard polimepca surface. After receiving the roller in the plant, the front cover is removed by placing the roller in the wheel and removing the damaged worn cover with a cutting tool. In one of many normal procedures for repolishing these rollers, the cutting tool is used to scrape the front cover leaving a fraction of an L rn of the front cover over the core of the steel roll. Then, the remaining fraction of 1 cover is removed by grinding. The roller cores are usually made of steel but are commonly formed of cast iron and tempered iron. After the grinding operation, the core of the rodil is subjected to sandblasting. The sandblast produces an activated surface on the metal core to optimize the bond with subsequent non-metallic materials that are formed on the roll core during the recovery operations. After having achieved an active surface by sandblasting, a protective layer, such as a phenolic ream or other suitable protective layer known in the art, is applied to the surface of the roller core. > ' > to avoid oxidation that could be re-produced from ot r-a mane-to the optimal union of the prepared surface. the pretreatment steps are normal and have been used in the roller coating industry for decades and do not form part of the present invention. In this example, before application of the compressive layer, a base coat is applied to the metal roll that has been pretreated as indicated above. The base layer is applied by a coating technique using the method and apparatus shown in Figure 4. In this embodiment, the roll is coated with a glass cloth 100 mm wide with 50% overlap while the roll It is spinning. The roller is sprayed simultaneously with a two-component epoxy resin system based on diglycidyl ether of bisphenol A, known commercially as DER 331 from Dow Chemical Co., and cured with an aromatic amine curing agent, diethyloluene na (DETDA 80) of Lonza Ag, Switzerland. The coating is continued for eight passes, a single pass extends the length of the roll, so as to comprise eight folds, and produces a base layer of 3 mrn in thickness. This layer is then gelled as the roller is subjected to a curing temperature of 50 ° C by means of heat lamps for a period of about 5 hours. The next step in the procedure is to prepare the surface for the joint. This is done by grinding the gelled base and then applying an adhesive to the surface J rough resulting. An epoxy-based adhesive is applied to the rough surface and then the septa fabric is applied on the same. The preferred separating fabric is a "Textile Spacmg Fabric", which can be purchased from MulLer TextLl GmbH, Postfach 31 40 D-5276 Uiehl -Di abenderhohe, Germany, the details of which are provided in a catalog that drops the product number 5556, incorporated herein by reference. As shown in Figure 10, this fabric can be thought of as an interleaf formed of an upper and a lower woven surface with a woven filling between them. This fabric is preferred because it is very compressible under pressure and is still rigid enough to be applied as a coating in subsequent steps. For this example, a material of 4 rnm thickness was purchased in widths of 1.5 meters, so that 4 pieces are required to cover a r-odallo of 6 meters. After the separating woven fabric has been sewn and secured to the base of the roll, it is covered with a side layer of 1 mm, which purpose is to avoid impregnation of subsequent resin material in the hollow cavities of the separating fabric. To achieve this, the woven separating fabric is coated around it with a non-woven tape impregnated with resin while the roller is rotated on a tor-no. The non-woven ribbon that is used is called Reernay and is obtained from Nordlys SA, 11 de l a Blanche, Maison 59270, Bailleul, France. It is a fabric made of polyester fibers. Before being applied to the roller, it is passed through a resin-to-epoxy immersion cell. Again, the epoxy resin is made from a bisphenol A dihydric ether, known commercially as DER 331 from Uow Chemical Co., but is cured with a alaratic amine,, 1ef farnine T-403, provided by Texaco Chemical Co. The two component parts that are necessary to produce the cured resin are fed to the immersion tank which also contains the amine curing agent to the phthalate. After having coated the roller in 2 passes with the nonwoven material impregnated with thermal setting resin, the resin in the material is gelifed at a temperature of 50 ° C for 2 hours, but it does not cure. In this step, the adhesive film prevents the liquid from the next step from penetrating through and towards the separating woven fabric while at the same time being sufficiently compressible to allow the contraction of the next layer to be absorbed by the separating fabric. The next step in the process is the application of the cover material, and in this example, it is applied by the coating process shown in Figure 4. However, in this step another nonwoven material formed of Kevlar is used. You get Kevlar, a product from DuPont, from Fermcal Fiber Products, Limited, Burnesside Mills, Kendall, Curnbpa LA9 6PZ England. The non-woven fabric used has a specification of 25 g / m2. Here, again, The epoxy resin is made from a diglycidyl ether of, >; Bisphenol A, and is it the same epoxid? used to form the protective gel cover, but with the aromatic amine curing agent used to form the base layer, d anientientol enod aini na (DE7DA 80) of Lonza Ag, Switzerland. The cover material is applied as a coating in this way. Using strips 100 nm wide, the coating procedure is ext noise for 20 passes in a triathlon or 50:50 to achieve a specified thickness which in this case is from? mrn. The next step in the procedure is to gel the top layer so that it is non-fluid. This is done by adjusting the roller ba or flashlights while the roller rotates for 15 hours at 70 ° C. After gelification, the ends of the coating are cut to provide an orme coating (tight). The adjustment is made just down the metal core. This is done with a cutting tool. Afterwards, the whole roller is transferred to an oven. The following curing cycle is cured: 8 hours at 80 ° C, followed by 8 hours at 90 ° C, followed by 8 hours at 100 ° C, and finally, followed by 16 hours at 110 ° C. Then, the roller is transferred to another oven for its cooling cycle. Allow to cool for 10 hours. Then the roller is taken to the production floor where the surface is prepared, usually grinding it to form an almost smooth but not finished surface. Before finishing the surface of the cover layer, the roller for the filling of the intermediate comprehensive layer 2b is prepared drilling holes through the cover towards the interlock of the separating woven fabric. Preferably, this is accomplished by drilling three holes in the roller extrusions at the locations shown in Figure 9 (the base and seal layers are not shown). The resin is inserted into the cavity of the intermediate separator fabric layer through the bottom hole 34 until it gushes out of the bottom hole 33 on the opposite side through the valve 40. When this occurs, the valve 40 closes and the cavity is filled with the resin until it flows out of the 4L valve. "Again, it is the same resin system that is used to seal the top layer for the separating fabric, that is, Bisphenol A epoxy resin. with an aliphatic amine curing agent. Before the insertion of the resin, the entire roller assembly is preheated in a furnace at a temperature of 75 ° C. Afterwards, the entire roller is cured in an oven at 75 ° C for 24 hours. During the entire treatment of this roller, a spreader can 35 has been placed on both ends of the roller. Each extendable can has an annular ring 36 which slides over the roller eq, equaling and extending the cylindrical metal surface outwardly along its longitudinal axis. Cylindrical cans are placed on both ends of the shaft. Ideally, this is done by having a wooden donut 36 where the donut fits over the roller axis and then this provides the edge of the can that extends the surface of the roller cover. It is important to note that the metal core of the roll core 37 and the squeeze cans 35 are treated with the coating methods described in the present. In this way, the metal base of the core of the Lo-rod and its spreader cans are covered with the base layer, the intermediate separating fabric layer, the indicator layer and the cover at the end of the process. The use of extender cans creates an additional vacuum to fill during the filling step of the intermediate layer, thus guaranteeing the complete filling of the inter-layer. Adornas, since the holes are drilled in the region of the spreader cans, the covers can be cut inside the boundary of the holes with which they present a finished product. The next part of this example is to cut through the different layers to the actual metal roller followed by * the removal of the two end pieces. The cut is made inside towards the location of the holes to produce a roller with finished covers. As final steps in the procedure, the cover is ground for finishing and the edges may be treated to form a light blister currently known in the art. In accordance with the previous example, Figure 12 shows a covered roller 1 having the upper cover 2 with a bevelled edge and a middle intermediate filled fabric layer 4 (the base and sealing layers are not shown). All the layers have been cut down to the core and the metal roller 5. The extendedoi can assembly (not shown) has been removed. Using the above specific example method, high performance coated rollers can be produced on a scale of thickness, intermediate layer and base layer. Specifically, the base "" and its associated manufacturing steps can be omitted completely by cementing the intermediate separating fabric directly towards a base of the metallic core of the roller, however, when a polymeapca base is used, it can vary in thickness to approximately three. The intermediate layer and its sealing layer can also vary in thickness - in the scale of approximately 2-15 nm, similarly, the thickness of the cover can vary in the range of 4-20 nm. In the above specification, the invention has been described with reference to specific exemplary embodiments thereof, however, it is evident that different embodiments may be made. modifications and changes thereto without departing from the spirit and scope of the invention, as indicated in the claims Therefore, the drawings and specification should be considered as illustrative rather than in a restrictive sense.

Claims (4)

1. NOVELTY OF THE INVENTION CLAIMS 5 1. A covered roller comprising: a roller core base; a compressive layer having an upper surface and a lower surface and an empty space therebetween, said compressive layer circumferentially surrounding said roller core core; one that surrounds 10 circumferentially integrates said compressive layer; said compressive layer is rigid enough to support said surrounding cover and sufficiently compressible to change volume in response to the volume changes occurring in said cover as a result of the efforts created during 15 his treatment.
2. 2. The covered roller according to claim 1, characterized in that said cover comprises an epoxy resin having a Shore-D hardness greater than 84 ..
3. 3. The covered roller in accordance with claim 2 , further characterized in that said cover is an epoxy resin that is cured at a temperature greater than 100 ° C.
4. 4. The covered roller according to claim 1, further characterized in that said cover is -. • > "=: form of a material that is cured at a temperature greater than 100 ° C. JO b. FL roller covered with confor i ad with Lamination 4, further characterized because said cover is an epoxy resin which is cured at a temperature greater than 100 ° C. 6. The roller covered in accordance with claim 2, also characterized in that the empty space of said compressive layer is filled with an epoxy resin cured at a temperature below the temperature at which the cover is cured. 7. The covered roller according to claim 1, further characterized in that said compressive layer comprises a fabric having a fibrous upper surface and a fibrous lower surface, said upper and lower surfaces being supported structurally by fibers that are extend from said upper surface toward the lower surface. 8. The covered roller according to claim 1, further characterized in that said compressive layer comprises a sheet having a single surface and a plurality of projections, the projections extending from said surface to define a substantially substantial limit. 9. The covered roller according to claim 1, further characterized in that the core core of the roller comprises a roller metal core. 10. The covered roller in accordance with claim 3, further characterized by the fact that the roller base of the roller comprises a metallic roller nipple. 11. The roller covered in accordance with claim 3, further characterized by the empty space. of said compressive layer is filled with an epoxy resin cured at a temperature below the temperature at which the cover is cured. J2. The covered roller according to claim 5, further characterized in that the empty space of said compressive layer is filled with an epoxy resin cured at a temperature below the temperature at which the cover is cured. The covered roller according to claim 7, further characterized in that the empty space of said compressive layer is filled with an epoxid resin cured at a temperature lower than the temperature at which the cover is cured. 14. The cover roller according to claim 0, further characterized in that the empty space of said compressive layer is filled with an epoxy resin cured at a temperature lower than the temperature at which the cover is cured. 15. A covered roller comprising: a roller core core; a filler member having at least one surface defining a filler region, said filler member circumferentially surrounding said core core of the filler; a cover circumferentially surrounding said filling member; wherein dLC has a filling region comprising a material cured at a temperature below the temperature at which the cover is cured. 16. A covered roller that starts: a roller core core; a filler member having a top surface and a bottom surface, these top surfaces being in a filler region, said filler member circumferentially meeting said roller core core; a cover surrounding the circumference of said filling member; wherein said filling region comprises a cured material at a temperature lower than the temperature at which the cover is cured. 17. The covered roller in accordance with claim 16, characterized in that said cover comprises an epoxy resin having a Shore-1) hardness greater than i) 4. 18. The covered roller according to claim 17, further characterized in that said cover is an epoxy ream that is cured at a temperature greater than 100 ° C. 19. The covered roller according to claim 16, further characterized in that said cover is formed of an atepal that is cured at a temperature greater than 100 ° C. ] 20. The roller covered in accordance with claim 19, further characterized in that said cover is an epoxy ream that is cured at a temperature greater than 100 ° C. 21. The covered roller in accordance with claim 16, further characterized in that the roller core core comprises a roller core metal. 22. The covered roller according to claim 18, further characterized by the base of the roller core. It comprises a roller metallic core. 23. The coated roller according to claim L6, further characterized in that said filling member compresses a fabric having a fibrous upper surface and a fibrous lower surface, said upper and lower surfaces are structurally supported by fibers that are extend from said upper surface towards said lower surface. 24. The covered roller according to claim 16, further characterized in that said filling member comprises a sheet having a single surface and a plurality of projections, said projections extending from said surface to define a limit subst ancí to the flat ment. 25. In a method for covering a roller in which a relatively hard cover material is applied on the core of the roller where the improvement comprises separating the cover of the kernel base of the roller to provide a space The circumferential intermediate between the core and the cover and fill the space between the core and the cover after the cover has been applied on the core. 26. The method according to claim 25, characterized in that the space is formed by a separating material, 27. The process according to claim 25, further characterized or that the space is filled in s1 u with the material separator. 28. The process according to claim 27, further characterized in that the filler material is polymer. 29. The method according to claim 25, further characterized in that the cover is applied to the compression layer as a resin impregnated tape as the roller rotates.