Abstract: An apparatus for heating plastic receptacles includes a transport device which transports the receptacles along a predetermined transport path and at least one heating device for heating the plastic receptacles. The heating device includes at least one radiation source which directs radiation at the plastic receptacles and at least one first reflector element which reflects radiation emitted from the radiation source. The apparatus includes a proportional reflection device which transmits radiation emitted by the radiation source with wavelengths in a first predetermined wavelength range onto the receptacle and reflects radiation with wavelengths in a second predetermined wavelength range onto the radiation source.

Abstract: Described is a method for chamfering the end of a pipe (2) made from thermoplastic material, comprising the following steps: localised and circumferential heating of an axial portion (3) of the pipe (2) at a predetermined temperature; plastic deformation of the heated axial portion (3) using a tool (4) for forming a chamfer on the axial portion (3).

Abstract: Disclosed are a heat transfer medium and a heat transfer method that uses the heat transfer medium. The heat transfer medium comprises a light-transparent substrate coated with a plurality of nano particles. The nano particles absorb light incident thereon to thereby produce heat, which is transferred to a target object to be heated. Nano particles can be applied onto a target object. After heating, the particles are removed by etching. Nano particles can be selectively applied to the light-transparent substrate or directly to a target object to be heat so as to localize heat-production and thus heat selective portions of the target object.

Abstract: Methods for fabricating a polymeric stent with improved fracture toughness including radial expansion of a polymer tube and fabricating a stent from the expanded tube are disclosed. The polymer tube is disposed within a mold and may be heated with radiation. The heated tube radially expands within the mold.

Abstract: A heating device for tempering preforms before processing in a stretch blow device. The heating device includes a heating alley with a plurality of infra red emitters, arranged parallel to the longitudinal axis of the tempered preforms. At least one back reflector and/or one filter is assigned to the infra red emitters, whereby the at least one back reflector and/or the at least one filter is segmented.

Abstract: A composite rod for use in various applications, such as electrical cables (e.g., high voltage transmission cables), power umbilicals, tethers, ropes, and a wide variety of other structural members, is provided. The rod includes a core that is formed from a plurality of unidirectionally aligned fiber rovings embedded within a thermoplastic polymer matrix. The present inventors have discovered that the degree to which the rovings are impregnated with the thermoplastic polymer matrix can be significantly improved through selective control over the impregnation process, and also through control over the degree of compression imparted to the rovings during formation and shaping of the rod, as well as the calibration of the final rod geometry. Such a well impregnated rod has a very small void fraction, which leads to excellent strength properties. Notably, the desired strength properties may be achieved without the need for different fiber types in the rod.

Abstract: Installation for heating the bodies (1) of thermoplastic preforms (2) with a view to manufacturing containers by blow-molding or stretch-blow-molding, while the preforms (2) are being moved along with their bodies (1) following a predetermined path (T), this installation comprising at least one directional source (5) of electromagnetic radiation directed towards a location (E) on the path (T); the source (5) is inclined by an angle (?) of between about 60° and 10° and preferably less than about 45°, with respect to the tangent (6) to the path (T) at the location (E); thus, the electromagnetic radiation can pass through several preform bodies or parts of bodies without being appreciably reflected back towards the source (5).

Abstract: A method of stretching a film in a longitudinal direction thereof by a difference in circumferential speed between front and rear rolls comprising radiating infrared rays onto the film from above the film and below the film with photo-concentration heaters wherein a represents an irradiated-area length in the longitudinal direction of an area of the film irradiated with converged light of the infrared rays radiated from above the film and b represents an irradiated-area length in the longitudinal direction of an area of the film irradiated with converged light of the infrared rays radiated from below the film, the area having the length a and the area having the length b overlap with each other, and a and b are each 10 mm or more to 40 mm or less.

Abstract: A method of making a microneedle array structure (20) comprising a plurality of simultaneously formed microneedles (24), each microneedle (24) having a protrusion (32) and a passageway (34) extending therethrough. The method comprises the steps of pressing an embossable sheet material between a complimentary tools and radiantly heating the sheet material using radiant energy from a radiant energy source. One tool is relatively-radiantly-transparent, and another tool and/or the sheet material is relatively-radiantly-absorptive.

Abstract: The present invention relates to a capacitor film comprising a biaxially oriented polypropylene wherein a) said polypropylene has a draw ratio in machine direction of at least 4.0 and a draw ratio in transverse direction of at least 4.0, and b) said polypropylene has an electrical breakdown strength EB63% according to IEC 60243-part 1 (1988) of at least 300 kV/mm at a draw ratio in machine direction and in transverse direction of 4.0.

Abstract: Methods for fabricating a polymeric stent with improved fracture toughness including radial expansion of a polymer tube and fabricating a stent from the expanded tube are disclosed. The polymer tube is disposed within a mold and may be heated with radiation. The heated tube radially expands within the mold.

Abstract: A method for producing a bent pipe from thermoplastic material with end cross-sections, central points of which have in relation to one another a positional tolerance on the basis of LN xy/JAR xy/FAR xy in relation to one another. A straight pipe element is introduced into a tool and a portion of the straight pipe element is heated that is located in the bending region to a temperature which lies above a glass transition temperature of the thermoplastic material by a first temperature value. The straight pipe element is bent about the heated bending region of the tool by a freely selectable bending angle, which has a spatial alignment in an XYZ system of coordinates that is fixed with respect to the pipe. The pipe is then cooled below the glass transition temperature by a second temperature value.

Abstract: A method is provided for removing a resin layer of a resin-coated metal tube. The resin layer is removed with a laser beam. More particularly, the resin layer of a desired range is burned out by focusing the laser beam into a pinpoint without defocusing the sectional shape of the laser beam in the axial direction o the resin-coated metal tube.

Abstract: The present invention discloses a device and a method for processing the impression structure of 3-layer co-extruded biaxial oriented polypropylene (BOPP) pearl synthetic paper. The depth of the impression on the synthetic paper is between 0.2-1000 ?m which is embossed by the modified embosser. The 3-layer co-extruded pearl synthetic paper is processed for cooling, biaxial orientation, corona treatment and winding and then passing through the modified embosser to preheating, calender, cooling. The modified embossing device comprises a rubber back-up roll having at least Shore A hardness of 60-90; an embossing roll with a designed pattern and a cooling system having a core; a quartz electric heating oven preheated to 65° C. to 160° C.; a infrared heater; and two adjacent cooling drums with 7° C.

Abstract: The objective of the present invention is to enable a microfilament that is a nanofilament to be manufactured continuously and consistently from all thermoplastic polymers without requiring a specialized high precision•high performance apparatus and also to present the nanofilament manufactured as described. The present invention comprises a microfilament in a nanofilament region and the manufacturing means thereof wherein a original filament transferred using a filament transfer means is supplied to an orifice under pressure P1 and is heated and drawn using an infrared light beam directly under the orifice under pressure P2 (P1>P2).

Abstract: The invention relates to a device and to a method for producing containers (2) such as bottles or drums, using preforms (3) preferably made of plastic, including the steps of supplying preforms (3), pre-heating the performs (3) by radiation in a heating module (5), and stretching and/or blowing the performs (3) by a blower (7), characterised in that the radiation has a wavelength between 1.5 ?m and 2 ?m and a device (1) for the production of containers (2) such as bottles or drums, using performs (3) preferably made of plastic, including a preform (3) conveyor (4), a heating module (5) including infrared emitters (6) and a bottle blower (7). The radiation has an emission peak corresponding to a wavelength between 1.7 ?m and 5 ?m, and the metal filament has an emission surface such that the ratio of the emitter input power to the filament emission surface is between 0.080 and 0.250 W/mm2.

Abstract: Catheters, balloons, and methods of manufacturing balloons for balloon catheters using lasers are disclosed. A catheter with a shaft sized for use with a 0.014 inch guide wire includes a polymeric balloon having a body portion with an inflated outer diameter of more than 6 millimeters. An inflatable balloon includes an inflated outer diameter to inner waist diameter ratio of 12.5 to 1. An inflatable polymeric balloon that has a body portion with two regions that have different molecular orientations is also provided. A method of processing an elongate polymeric material includes heating a portion of the polymeric material with a laser while longitudinally stretching the portion of the polymeric material. A method of manufacturing a balloon includes heating and longitudinally stretching a first and second portion of an elongate polymeric tube to form first and second end portion. The remaining body portion is radially expanded to form the balloon.

Abstract: The invention relate to a process for forming a cured, partially cured or uncured thermosetting material, comprising: an irradiation step wherein the thermosetting material is exposed to electromagnetic radiation which to a significant extent is within the neat-infrared range in such a way that the temperature of the irradiated thermosetting material is brought to between 40° C. and 400° C., and a forming step wherein the irradiated thermosetting material is brought into a desired shape, whereby the forming step is executed during and/or subsequent to the irradiation step. The invention also relates to an apparatus for carrying out the said process and to a thermosetting material.

Abstract: A molded product includes a matrix formed of a polymer material and a plurality of capsules dispersed in the matrix. An unevenness is formed on a surface due to expansion of the capsules. Some of the capsules have expanded without bursting and include an exposed outer shell portion that protrudes from a surface, and/or some of the capsules have burst and include an outer shell protruding portion that protrudes outward from the surface. Finish processing is performed, which eliminates the outer shell protruding portions and/or the exposed outer shell portions from the surface. This results in a molded product in which a color difference due to frequency of contacting an object, etc. is not easily generated.

Abstract: The object of this invention is to make possible the manufacturing of sheath-core type super microfilaments from sheath-core type filaments such as hollow filaments, optical filaments and conjugate filaments continuously and stably by a simple and convenient means without requiring any apparatus of high-accuracy and high-level, characterized in that original filaments delivered from sheath-core type filament supply means are heated by infrared beams and the heated sheath-core type filaments are drawn at 100 times or more by a tension provided by the own weight or under a tension of 1 MPa or less.

Abstract: The objective of the present invention is to enable a microfilament that is a nanofilament to be manufactured continuously and consistently from all thermoplastic polymers without requiring a specialized high precision.high performance apparatus and also to present the nanofilament manufactured as described. The present invention comprises a microfilament in a nanofilament region and the manufacturing means thereof wherein a original filament transferred using a filament transfer means is supplied to an orifice under pressure P1 and is heated and drawn using an infrared light beam directly under the orifice under pressure P2 (P1>P2).

Abstract: A process for the production of a polymeric film comprising a copolyester having an acid component and a diol component, said acid component comprising a dicarboxylic acid and a sulfomonomer containing a sulfonate group attached to the aromatic nucleus of an aromatic dicarboxylic acid, said process comprising the steps of: (i) melt-extruding a layer of said copolyester; (ii) stretching the extrudate in at least one direction; (iii) heat-setting the film by raising the temperature of the stretched film to a temperature T1 in a first heating zone such that (TM-T1) is in the range of from 5 to 30° C., and then raising the temperature of the film to a temperature T2 in a second heating zone such that (TM-T2 is in the range of from 0 to 10° C.

Abstract: Catheters, balloons, and methods of manufacturing balloons for balloon catheters using lasers are disclosed. A catheter with a shaft sized for use with a 0.014 inch guide wire includes a polymeric balloon having a body portion with an inflated outer diameter of more than 6 millimeters. An inflatable balloon includes an inflated outer diameter to inner waist diameter ratio of 12.5 to 1. An inflatable polymeric balloon that has a body portion with two regions that have different molecular orientations is also provided. A method of processing an elongate polymeric material includes heating a portion of the polymeric material with a laser while longitudinally stretching the portion of the polymeric material. A method of manufacturing a balloon includes heating and longitudinally stretching a first and second portion of an elongate polymeric tube to form first and second end portion. The remaining body portion is radially expanded to form the balloon.

Abstract: In a polymer film stretching system, a tentering machine draws polymer film of cellulose acylate containing additive of triphenyl phosphate in a transverse direction while the polymer film is guided continuously and heated. A stretching chamber contains the tentering machine. A far infrared heater and heat roller heat the polymer film before entry to the stretching chamber to set temperature of the polymer film upon entry to the stretching chamber in a range equal to or higher than T+10 (deg. C.) and equal to or lower than T+80 (deg. C.), where T (deg. C.) is a condensation temperature of the additive evaporated in the stretching chamber. Furthermore, a film dispenser supplies the polymer film from a film roll to the tentering machine.

Abstract: A plastic end disk for a hollow-cylindrical filter element has an end face plastic layer and a neighboring plastic layer. The end face plastic layer is transparent for infrared radiation. The neighboring plastic layer is absorbent for infrared radiation. The plastic end disk is connected to a folded filter medium in that the end face plastic layer is trans-irradiated with an infrared radiation source, wherein the infrared radiation is absorbed in the neighboring plastic layer so that a portion of the neighboring plastic layer and a portion of the end face plastic layer are completely melted. The infrared radiation source is removed and the filter medium is pressed into a melted area of the end face plastic layer. The filter medium is secured in the pressed-in position in the end face plastic layer until a fixed connection of filter medium and end face plastic layer has been formed.

Abstract: A method of embossing a sheet material includes: heating at least a portion of the sheet directly or indirectly with radiant energy from a radiant energy source; pressing a tool against the heated portion of the sheet, thereby patterning a surface of the sheet; and separating the sheet and the tool. The radiant energy may travel through a solid material that is relatively transparent to radiation, on its way to being absorbed by a relatively-absorptive material. The relatively-transparent material may be an unheated portion of the sheet, and the relatively-absorptive material may be either the tool or the heated portion of the sheet. Alternatively, the relatively-transparent material may be the tool, and the relatively-absorptive material may be all or part of the sheet. The method may be performed as one or more roll-to-roll operations.

Abstract: The present invention provides a method of planarizing a substrate with a template spaced-apart from the substrate having a liquid disposed therebetween, the method including: contacting the liquid with the template forming a first shape therein; and impinging radiation upon the liquid causing a reduction in volume of the liquid, with the first shape compensating for the reduction in volume such that upon impinging the actinic radiation upon the liquid, the liquid forms a contoured layer having a substantially planar shape.

Abstract: The invention relates to a method for producing plastic profiles comprised of at least one hard profile strand (2), for example, consisting of hard PVC, and of at least one soft profile strand (1), for example, consisting of soft PVC, whereby both profile strands (1, 2) are simultaneously produced by separate extrusion nozzles (20, 17a) and are cooled in a cooling device (16, 18). A secure joining can be effected using simple means by leading the soft profile strand (1) directly out or the extruder (17) and into a cooling bath (16, 18), inside of which it is completely cooled, and the hard profile strand (2) and the soft profile strand (1) are subsequently joined under pressure.

Abstract: Method of and apparatus for continuously manufacturing highly oriented super micro filaments with a diameter of 5 ?m or less from most of thermoplastic polymers stably by a simple and convenient means without requiring any special apparatus of high accuracy and high level, characterized in original filaments supplied from a filament supply means are heated by infrared beams and the heated filaments are drawn by tension provided by their own weight or under an applied tension of 1 MPa or less, and are drawn to 1000 times or more.

Abstract: The invention is a method of a sheet (134) of thermoplastic material between upper and lower molds (102, 104), heating the sheet to a plastic state using electromagnetic radiation and molding the sheet. The molds (102, 104) are preferably formed of silicon and infrared radiation is preferably used to heat the sheet (134).

Abstract: A transfer device in which a material which transmits a laser beam LB is employed as an upper mold, and a photothermal conversion layer is formed thereon. A transfer film, at which a transfer material layer is formed, and a workpiece are superposed and pressured between the upper mold and a lower mold. During this pressuring, the laser beam is irradiated in accordance with a pattern of an organic electroluminescent light-emitting layer that is to be formed on the workpiece. Thus, the photothermal conversion layer is heated and the transfer material layer is softened. As a result, the transfer material layer is cleaved and detached from a temporary support, and a component in the transfer material layer that is to form the organic electroluminescent light-emitting layer is transferred to the workpiece. Accordingly, efficient transfer processing is enabled when a transfer material is transferred to a transfer object by a thermal imaging process.

Abstract: The invention relates to a method in connection with processing polymer or elastomer material, wherein additive is added to the polymer or elastomer material, and the additive is subjected to the desired chemical reaction. To minimize energy consumption, infrared radiation is led to the polymer or elastomer material, the wavelength of the radiation being so chosen that the radiation penetrates optimally the polymer or elastomer material, but absorbs in the additive, producing the desired reaction in the additive.

Abstract: A method of embossing a sheet material includes: heating at least a portion of the sheet directly or indirectly with radiant energy from a radiant energy source; pressing a tool against the heated portion of the sheet, thereby patterning a surface of the sheet; and separating the sheet and the tool. The radiant energy may travel through a solid material that is relatively transparent to radiation, on its way to being absorbed by a relatively-absorptive material. The relatively-transparent material may be an unheated portion of the sheet, and the relatively-absorptive material may be either the tool or the heated portion of the sheet. Alternatively, the relatively-transparent material may be the tool, and the relatively-absorptive material may be all or part of the sheet. The method may be performed as one or more roll-to-roll operations.

Abstract: A method and apparatus for forming a mechanical fastener. A preferred embodiment of the method includes moving a substrate along a web path, where the substrate includes a first major surface and a plurality of stems extending from the first major surface of the substrate and each of the stems includes a stem end, radiantly heating the stem ends to form softened ends, and thereafter deforming the softened ends into convex heads with a deformable surface. A preferred embodiment of the apparatus includes a web conveyor, where the web conveyor defines a web path, a heating source located adjacent the web conveyor and a deformable surface located down the web path from the heating source, where the deformable surface includes a durometer hardness of greater than 10 Shore OO and less than 70 Shore A.

Abstract: An apparatus for heat staking utilizes an infrared lamp to direct radiant energy onto a plastic part to heat and so soften it prior to the staking punch impacting the part. The apparatus comprises an energy directing means for concentrating the infrared energy onto the part, and a moveable carriage for moving the punch toward and away from the part. One embodiment of the energy concentrating means is a reflector, wherein the reflector includes a central aperture for admission of the part, and wherein the reflector comprises different curved sections for concentrating the energy over the surface of the part. In an alternate embodiment, the energy directing means comprises fiber optic cables for directing the infrared energy to the surface of the part.

Abstract: This invention provides a method of producing a biaxially stretched polyester film with regulating casting conditions of a polyester film at a high speed so as not to induce surface defects caused by entrapping air microbubbles between a cooling drum and a molten resin sheet, and regulating longitudinal stretching conditions and lateral stretching conditions. The biaxially stretched polyester film is excellent in small thickness variation, resistance to cleavage and improvement in bowing phenomenon, and is particularly suitable for the support of a photographic film.

Abstract: The invention concerns an improved method of heating or tempering foils and an associated device including an arrangement for measuring the temperature, based on the following features: a separate arrangement is provided for heating the foil edges; the foil edge heating arrangement comprises an infrared radiator device (21) and a hot air heating device (29); and the infrared radiator device (21) and the hot air heating device (29) can be controlled or set at different heating output values.

Abstract: A head for use in a heat staking machine utilizes an infrared heat lamp and reflectors to direct radiant energy onto a plastic stud to heat and so soften it prior to the staking punch impacting the stud. The lamp is disposed within a parabolic primary reflector which directs the lamp's output toward a secondary reflector. The secondary reflector has is concave and has a central aperture at its vertex through which the stud projects such that all of the radiant energy emitted by the lamp is focussed radially inward onto the stud. The punch is slidably mounted to the primary reflector for reciprocal movement along the axes of the reflectors, and is extended to impact the stud.

Abstract: A for the production of polymeric fibers in the form of a tow includes drawing and heat setting, with and without crimping, in which the tow has a constant denier per inch during the processing. The process permits very large drawn tows to be produced having a thickness of at least 150,000 denier per inch of width during processing through the production equipment/apparatus. The production apparatus includes a conventional stacker, followed by drawing apparatus, followed by heat setting apparatus, and optionally followed by crimping apparatus. Positioning the stacker before the drawing apparatus allows very large tows to be produced using drawing and heat setting apparatus having rolls significantly shorter than is conventionally known.

Abstract: A method of heat-setting garments by boarding the garment and subjecting it to preselected temperatures that are different for different parts of the garment and an apparatus for carrying out this method are provided.

Abstract: A method for forming a socket on a pipe of biaxially oriented polyvinyl chloride including: placing a support in an end section of the pipe, heating the pipe in the region of the end section; deforming the pipe to produce a socket in the region of the heated end section, the heated end section being supported internally while the socket is being formed; cooling the pipe in the region of the end section, the end section being supported internally during the cooling operation; and removing the support from the pipe. For the purpose of heating the internally supported end section of the pipe, the end section is first heated until the end section has reached, substantially homogeneously, the glass transition temperature of polyvinyl chloride and is then further heated until the end section has reached, substantially homogeneously, a temperature near, preferably just above, the orientation temperature of polyvinyl chloride.

Abstract: A plastic sheet capable of being shaped by a cold room temperature tool, said sheet being a semi-rigid thermoformable plastic foam doped with carbon black having a concentration within a range of 0.0000081 to 0.0081% by weight of the foam. And a method of forming a product from such sheet by heating it to its thermoforming temperature range by infrared (IR) heat and placing and compressing the sheet between mold parts of a cold tool, the IR heat preferably being generated by quartz lamp electric heaters.

Abstract: The invention relates to a process for heating polymer material, including irradiation of said polymer material with infrared radiation. In accordance with the process according to the invention the infrared radiation has wave lengths which substantially are not equal to the absorption peaks of the polymer material in respect of infrared radiation.

Abstract: A machine for heat staking utilizes an infrared heat lamp to direct radiant energy onto a plastic stud to heat and soften the plastic material prior to the staking punch impacting the stud. In a first embodiment of the invention, the lamp is mounted directly above and in coaxial alignment with the staking punch such that the lamp points downward toward the plastic stud. An annular reflector is positioned in a radially surrounding relationship to the stud such that all of the radiant energy emitted by the lamp strikes the reflector and is redirected radially inward onto the stud. In an alternate embodiment of the invention, an infrared lamp is mounted on a non-moving portion of the staking press machinery and one or more fiber-optic cables extend from the lamp to the vicinity of the stud. The fiber-optic cables gather substantially all of the radiant energy produced by the lamp and direct it onto the stud.

Abstract: In a method for the arc-like shaping of an extruded profiled strand of plastic material at least a section of the strand is heated in a hot air chamber together with a support ledge disposed in spaced relationship from the profiled strand to a temperature permitting the bending of the profiled strand and the strand is then firmly engaged between a support ledge at the inner compression side and a support profile at the other, that is the tension side of the profile strand to form a package, which is then bent while the temperature at the compression side of the profile strand is higher than the temperature at the tension side thereof to prevent the formation of waves in the profile strand walls. The invention also resides in a heating apparatus, which provides for the temperature difference at opposite sides of the profile strand and includes means for engaging the profile strand during bending.

Abstract: A method for forming a bend in a tube of thermoplastic material by heating a pre-formed bend to a pre-determined temperature and maintaining the temperature substantially constant by the pulsed emission of infra-red radiation from one or more infra-red sources in response to the surface temperature of the tube detected by a remote temperature sensor.

Abstract: A candle has an elongated wax body formed around a wick and having a tip from which the wick projects and which is formed with a shoulder. The candle is oriented upside down with the tip from which the wick projects directed downward and heat is projected against a surface of the tip to melt wax on the surface of the tip such that the melted wax runs down and drips off the candle tip and wick projecting therefrom. Heat is projected against the tip by directing a hot-air jet against the tip. Alternately this can be done by projecting infrared radiation against the tip. To achieve the most attractive results the candle is rotated about a central longitudinal candle axis while projecting heat against its tip.

Abstract: An improved process for simultaneous biaxial stretching of a thermoplastic polymer film having beaded edges in a tenter frame consisting of gripping the beaded edges of the film with tenter clips and increasing the temperature of the beaded edges to within the film orientation temperature range prior to or during simultaneous stretching, and in subsequent stretching or heat-setting steps, by focusing heat on the beaded edges of the film. Thermoplastic films, such as polyethylene terephthalate and polyethylene naphthalate, having a final thickness of from 0.2 to 350 microns after simultaneous stretching can be prepared.

Abstract: A method and apparatus for producing highly-oriented polyester sheet comprises a two-stage drawing process. The first drawing stage is performed within a zero-gap milling and stretching roller assembly comprising a pair of opposed rollers defining a nip therebetween and wherein the rollers are rotated in opposite directions at different lineal surface velocities such that a predetermined draw ratio is defined therebetween. Amorphous polyester sheet is conducted through the nip of the opposed rollers, and as a result of the simultaneous milling and stretching of the polyester sheet, the amorphous polyester is transformed into crystalline polyester as a result of orientation-induced crystallization. The crystalline polyester sheet is heated above the glass transition temperature (T.sub.g) immediately downstream of the nip defined between the pair of opposed rollers, and an exit bridle assembly is disposed downstream of the pair of opposed rollers.

Abstract: An apparatus and method for producing an oriented plastic strap having a predetermined desired thickness and flatness characteristics for use in connection with the strapping of packages or the like, is disclosed. A sheet workpiece is conducted into a nip defined between a pair of opposed milling and stretching rollers wherein one of the rollers is rotated at a lineal surface velocity which is greater than the lineal surface velocity of the other roller, and the rollers are rotated in opposite directions. One of the rollers effectively brakes or retards one of the surfaces of the sheet workpiece while the other one of the rollers effectively accelerates the other one of the surfaces of the sheet workpiece as the workpiece passes through the nip defined between the rollers whereby the workpiece is simultaneously milled and stretched.