Abstract: Method of forming a plate including providing a sheet of polyethylene terephthalate foam and thermoforming the polyethylene terephthalate foam into a plate. The plate comprising a bottom wall having an outer perimeter, an upper surface, and a lower support surface defining a horizontal reference plane. The plate further comprising a sidewall extending upwardly and outwardly from the outer perimeter at an angle “a” of between about 30° to about 35° relative to a vertical axis perpendicular to the horizontal reference plane. The plate further including a rim extending laterally outwardly from an upper edge of the sidewall and a turndown flange extending downwardly from an outer edge of the rim and terminating at a free end.

Abstract: The device includes a mold block having at least one thermoforming chamber (28) having an inside surface (29), an axial opening (28A) through which a decorative wrap-around label (38) can be inserted into the chamber, and a moving end-wall (40) opposite from the opening. The end-wall is suitable for moving in an end segment (28A) of the chamber (28) between a positioning high level and at least one thermoforming low level, and the device has at least one tongue-and-groove set comprising a fin (42) on the end-wall (40) that is engaged in a notch (44) in the inside surface of the end segment (28B).

Abstract: A device for blow molding containers. Preheated preforms made of a thermoplastic material are transferred within a blow molding machine to a blowing device. In the region of the blowing device, the preforms are shaped into containers by the blow molding by a blowing pressure. In the region of the device for blow molding containers, a blowing nozzle seal is arranged, which is brought against a support ring of the preform. The blowing nozzle seal is formed by a sealing element and a support sleeve. The blowing nozzle seal is first mechanically preloaded in relation to the support ring after contact with the support ring and then is further loaded pneumatically. An accommodating space that surrounds the mouth section of the preform is thereby provided, which accommodating space has substantially the same pressure as the interior of the preform in order to avoid deformation of the mouth section.

Abstract: A device for blow molding containers. Preheated preforms made of a thermoplastic material are transferred within a blow molding machine to a blowing device. In the region of the blowing device, the preforms are shaped into containers by the blow molding by a blowing pressure. In the region of the device for blow molding containers, a blowing nozzle seal is arranged, which is brought against a support ring of the preform. The blowing nozzle seal is formed by a sealing element and a support sleeve. The blowing nozzle seal is first mechanically preloaded in relation to the support ring after contact with the support ring and then is further loaded pneumatically. An accommodating space that surrounds the mouth section of the preform is thereby provided, which accommodating space has substantially the same pressure as the interior of the preform in order to avoid deformation of the mouth section.

Abstract: An apparatus and method for forming cavities in pouches. The packages are used for packaging sterile medical products. The apparatus has a frame and a tongue plate member. A pouch is placed onto the tongue plate member to form a cavity into at least one side of the pouch.

Abstract: Apparatus and methods of forming selected portions of integral sheets of material are disclosed. Unformed portions of the sheets may remain undistorted during the forming process, allowing them to contain text, art work, or other desired information without material risk of the information being degraded or becoming unintelligible during the forming process. This result may be accomplished, moreover, with less trim than usually occurs in conventional forming processes.

Abstract: A microstructured composite component is provided including structures for carrying out fluid processes. A device is provided for producing microstructured composite components. A method provided includes a first step during which a first film is arranged above a second film between first and second mold parts. The first and/or second mold parts have microstructured cavities to be filled. In a second step, the first and second mold parts are heated in at least one region in which they contact one of the films. An excess pressure is then produced between the first film and the second film to force the first and/or second films into the cavities. In a further step, the first and second mold parts are pressed together by a pressing force. Once the first mold part, the second mold part, the first film and the second film are cooled, they form a microstrutured composite component.

Abstract: Processes for manufacturing hollow structures such as spars for helicopter rotor blades, fixed wings for aircraft, and other aerostructures can include the provision of a path for gases to exit the material from which the spar is formed as the material is heated and cured, to help eliminate voids within the material caused by the presence of such gases.

Abstract: According to one embodiment, a distribution assembly is used to distribute a load of liquid containers. The distribution assembly may include a slip sheet, a pallet divider, and a rotating pallet. The slip sheet may be designed to laterally group two or more liquid containers. The pallet divider may divide the load into sections, each section containing a stack of liquid containers. The pallet divider may restrict access to one of the sections to distribute the liquid containers of the other section. The rotating pallet may rotate the load to allow the other section to be accessed.

Abstract: Separator for cylindrical cell of the outwardly guided type, wherein a sheet material is wound around a mandrel, and starting from the winding step until the insertion of a separator into the cell, an outward support is used that renders the binding of neighboring turns of the separator winding unnecessary, and the separator sheet has an extended portion, with the extension being at least equal to the radius of the separator cylinder, and with this extended portion being wetted with distilled or de-ionized water until the material softens and the winding and the mandrel are rotated and the bottom part is folded back and heat fused to close the separator cylinder.

Abstract: A curved composite aircraft frame comprises a multi-ply composite laminate having a generally Z-shaped cross section. At least certain of the laminate plies include unidirectional reinforcing fibers that are substantially tangent at substantially all points along the curvature of the frame.

Abstract: A blowing apparatus for expanding containers with a gaseous medium has a blowing piston and a blowing nozzle, through which the container is expanded with the gaseous medium. The blowing piston is movable in a longitudinal direction (L) of the blowing nozzle, the blowing nozzle is movable in the longitudinal direction (L) relative to the blowing piston, and a guide device is provided which guides the movement of the blowing nozzle in the longitudinal direction (L) relative to the blowing piston.

Abstract: Method and system for making a product (1) having a solid body (2) and having one or more cavities (3, 15) inside that solid body, with a broad surface and a small thickness. A liquid material is provided within a mold (4), and solidification of the liquid material is controlled in a position dependent way from the outside of the product. When using a thermoplastic material, the system may cool said liquid material less in areas that are projections of the cavities on the outside of the product on its broad surface. When using a thermosetting material the system may include means (5, 9) for controlled heating the liquid material, excluding the projections of the intended cavities. Once part of the product has sufficiently solidified outside the intended cavities the liquid material is driven from the intended cavities by means of a fluid. In the product some cavities may be provided with a conductive layer or structure, e.g.

Abstract: The present invention provides a method for manufacturing a walk-in bathtub. The method involves heating an acrylic sheet, wherein the outer perimeter of the sheet is heated to a higher temperature than the center of the sheet. The heated acrylic sheet is then placed over a vacuum mold that is shaped like a bathtub, including a seat and a foot well, and drawn into the mold by the vacuum. Vacuum pressure is manually reduced when the acrylic reaches the top of the seat in the mold, and the vacuum is shut off when the acrylic is approximately two inches from the bottom of the foot well of the mold. The acrylic is removed from the mold, reinforced with fiberglass and secured to a support frame. A door space is cut in the side of the tub and a pre-hung door assembly is then installed in the door threshold.

Abstract: A slip sheet is thermoformed as a single-piece plastic sheet body to include a lower surface with a first set of features and an upper surface with a second set of features. The slip sheet is to be positioned between adjacent layers of stacked containers such that the first set of features interfaces directly with container tops and the second set of features supports the container bottoms. The slip sheet includes a hinge that allows one portion of the sheet body to be pivoted relative to another portion of the sheet body to provide access to a lower layer of containers.

Abstract: A decorative architectural panel can be formed using multiple image layers to create one or more three-dimensional effects in a final product. In particular, a reference image layer comprises an extruded sheet having an artistically-designed reference image formed thereon. A next image layer comprises an extruded sheet having a differently sized iteration of the artistically designed reference image. A manufacturer can place the next image layer over the reference image layer, and set the combined image layers such that the final product shows the artistically-designed image in three-dimensions. Additional image layers, such as a color layer, or a layer having embedded objects, can be combined with the stratified product for additional artistic effects.

Abstract: A method of forming a balloon to be attached to a medical catheter involves drawing a cylindrical balloon base in its circumferential direction and/or its lengthwise direction, while the inside and/or outside of the balloon base is in contact with a fluid in a supercritical state for the balloon base to be modified.

Abstract: A method and an apparatus for continuously producing elongated siding panels is disclosed. The apparatus includes a conveyor, a plurality of mold plates, and a die for extruding a sheet of material onto the mold plates. The mold plates are formed of a rigid material and positioned adjacent one another and supported by the conveyor for forming the elongated siding panels. Each of the mold plates has an upper edge portion and a lower edge portion with an intermediate portion therebetween. The intermediate portion has an aesthetic pattern for imparting the pattern to the sheet of material with the adjacent mold plates having different aesthetic patterns. The lower edge portion has a lower leg extending substantially perpendicular from the intermediate portion defining a horizontal plane and a projection portion between the lower edge portion and the intermediate portion extends beyond the horizontal plane for imparting a jagged pattern to the intermediate portion.

Abstract: The invention relates to a method and device with which it is possible to arrange complicated shapes with considerable differences in height in wood fibre board, and in particular but not exclusively so-called MDF (Medium Density Fibreboard). The deformation of the wood fibre board which can be achieved with the invention is known in the art as extrusion, wherein a considerable plastic deformation takes place accompanied by flow and stretch of the material.

Abstract: A method and apparatus are provided for forming a sheet of polymeric material, such as polycarbonate. A forming mold is provided having halves that engage for forming a heated sheet therebetween. Each of the halves defines an interior cavity having a peripheral edge. The sheet is retained between the peripheral edges of the halves and a vacuum is generated within one of the cavities for drawing the sheet therein, whereby a sensing mechanism detects a draw depth for initiating a cooling mechanism to cool the sheet to a temperature below a glass transition temperature of the material. A series of retention mechanisms are provided about the peripheral edge of one of the halves, for biasing the sheet into engagement with the peripheral edge of the opposing half. A trimming mechanism is further provided for trimming the perimeter of the sheet to a desired form.

Abstract: A drumhead mold and process for making a plastic drumhead. The mold is structured to heat the drumhead collar area and maintain the battering surface cool to provide a drumhead with improved performance characteristics.

Abstract: What is described is a method for producing a thermally shaped substrate coated with a sol-gel coating material, in which the sol-gel coating material comprises one or more hydrolyzable silanes, which may have been hydrolyzed to form a precondensate, and, if desired, a crosslinking agent, at least some of the hydrolyzable silanes containing on a non-hydrolyzable substituent a functional group by way of which crosslinking is possible, and in which A) the sol-gel coating material is applied to a thermally shapable substrate, B) the applied sol-gel coating material is partially precrosslinked and/or dried, C) the substrate coated with the sol-gel coating material is subsequently shaped thermally, and D) during and/or after the thermal shaping the sol-gel coating material is cured completely by means of thermal or photochemical crosslinking.

Abstract: A high-temperature, non-catalytic, infrared heater is formed within a housing having a bottom and at least one side lined with a refractory material. The burner includes a burner surface area and is positioned within the housing. A re-radiating surface is positioned above the burner and comprises a mesh having a re-radiating surface area greater than the burner surface area with the re-radiating surface operating between approximately 400° F. and 2200°F.

Abstract: A photo film cassette includes a spool core (13) on which photo film is wound in a form of a roll. A cassette shell (3, 4) contains the spool core in rotatable fashion. In each of a pair of disks (16, 17), a bearing hole (16a, 17a) is formed. The disks are secured to first and second ends of the spool core, and regulate edges of the photo film. To produce at least one kind of disk, a continuous sheet (27, 78, 88, 162, 171, 215) of thermoplastic synthetic resin is partially masked with a mask plate (48, 87, 160, 161, 170). A portion of the sheet emerging out of the mask plate is heated at temperature higher than a softening point of the sheet. The emerging portion is subjected to vacuum/air-pressure forming, so as to form a disk-like portion (20) in the sheet. The bearing hole and a contour of the disks is cut in the disk-like portion, to produce the disks.

Abstract: Methods for pre-shaping paint film laminates and co-molding processes using such laminates are disclosed. The methods comprise the steps of providing (e.g., forming or procuring) a plastic paint film laminate, softening the paint film laminate with heat such that one or more localized portions of the member absorb more heat than the remainder, and deforming the plastic film member to form a pre-shaped article. The formation of different heat absorption areas on the paint film laminate is referred to as the provision of heat sink areas. These heat sink areas can be provided for example by surface coating of heat retention means such as black paint or ink pigments on localized areas of the surface of the laminate followed by uniform heating of the laminate in an oven or the like or the sheet can be heated in localized areas to a greater extent (i.e. time and/or temperature) than in remainder portions by the means of heat guns or the like.

Abstract: A method of heating a film prior to thermoforming by the following steps. A thermoplastic flexible film having a painted surface and a thermoplastic backing sheet is placed within a frame. The frame and film are placed within a heater. The heater has first and second radiating surfaces. The first and second radiating surfaces are parallel to the ground and the first radiating surface is above said second radiating surface. The first radiating surface is opposite the backing sheet and the second radiating surface is opposite said painted surface. The backing sheet is heated to a first temperature sufficient to cause the backing sheet to become pliable. The first temperature is a first difference above ambient temperature. The painted surface is heated to a second temperature. The second temperature is a second difference above ambient temperature and the first difference is between 2 to 20 times greater than the second difference.

Abstract: In manufacturing a photo film cassette, a disk producing apparatus includes a web supplier which conveys the web from a web roll to the web conveyor. The web conveyor includes two chains which convey the web in an intermittent fashion, and which include pointed portions which serially penetrate an edge portion of the web. A heater disposed upstream from the web conveyor heats the edges of the web. At the heating/forming unit, a heating plate is lowered toward the web at the same time as the female mold is raised toward the web, and the web is squeezed between them before the heating and vacuum/air pressure forming takes. Clampers/coolers disposed upstream and downstream from the heating plate and female mold squeeze the web in fixed fashion to prevent wrinkles on the web. A web/sheet cutter device includes an upper punch above the web and a lower die under the web, which squeeze the web, and cut the web into a sheet having a plurality of disk-like portions.

Abstract: The invention relates to hard sided luggage shells and other containers manufactured using vacuum forming or pressure forming of thermoplastics. A process for making shells and containers with integrally molded frames is disclosed, and products made by the method. A method of manufacturing differential pressure formed containers with framed openings, but without the need to attach a separate frame element to the molded shell. A process also is disclosed for reducing the undesirable stretching of shell material that occurs during differential pressure forming, particularly the thinning of corner portions of the shell or container. The process of the invention more efficiently utilizes the thermoplastic material by moving material from otherwise offal portions into the molded product. An improved method for severing the offal material from the final product is disclosed.

Abstract: A method of forming blister pack packaging is provided including providing a thermoplastic material and placing the thermoplastic material between a pair of opposed male and female thermoforming dies, while cooling a portion of at least one of the dies. The cooled portion of the die is positioned to contact the area of the thermoplastic material in which it is desired to avoid distortion.

Abstract: The disclosure is directed to a differential temperature vacuum forming tool having differentially heated sections. In a specific application, vacuum formed plastic buttons with indicia thereon are produced without distortion of the print indicia. The vacuum forming tool accepts a printed plastic overlay for shaping; and the shaped printed plastic overlay can be used to produce back-lit buttons.

Abstract: A method of forming a three-dimensional object (38) is provided using a combination of molding and machining. In its most basic form, the method of the present invention is achieved by depositing a first layer of mold material (40) onto a support surface (20), machining a first cavity (42) into the first layer of mold material, depositing a first layer of construction material (52) onto the first layer of mold material such that an overlapping portion (52a) of the first layer of construction material fills the first cavity to form a first three-dimensional section of the object and such that a superposing portion (52b) of the layer of construction material covers the first layer of mold material, and machining the superposing portion (52b) to form a second three-dimensional section of the object. A larger object may be produced by repeating such steps in like sequence to form additional three-dimensional sections.

Abstract: A process for producing a formed article by heating a thermoplastic resin sheet and then thermoforming a part to be formed involves heating the part to be formed by placing in contact with a heating plate while at least a part of a non-formed part of the thermoplastic resin sheet is not heated by placing in contact with the heating plate, and then heating the part to be formed and at least a part of the non-formed part by placing them in a non-contact state with a heating means is disclosed.

Abstract: A process for producing a thermoformed article having a first portion with a first wall thickness, and a second portion with a second wall thickness, the first portion having a thicker wall thickness than the second portion, the process including selectively cooling the first portion during a thermoforming cycle so that thermoformable material from the first portion is prevented from migrating to the second portion.

Abstract: An apparatus with pivoting blades and closable surfaces for forming a sheet of material into a flower pot or flower pot cover having fins. In an embodiment for forming outwardly extending fins, the apparatus includes a male mold and a plurality of plates arranged in pairs to define a forming opening. The male mold has a plurality of fingers which are laterally extendable from the outer periphery of the male mold. A pneumatic or hydraulic piston and cylinder is provided to move the male mold between a storage position spaced from the forming opening and a forming position within the forming opening. Each pair of plates is movable between an open position and a closed position. In operation, the fingers are extended to push folded portions of a sheet of material between the pairs of plates, which are closed to press the folded portions into fins. In an alternate embodiment for forming outwardly extending fins, pairs of movable plates are positioned between stationary segments.

Abstract: Methods for the formation of biaxially oriented thermoplastic articles having flat surfaces or sharp contours, along with the articles themselves. Such methods relate to blow forming a sheet of unoriented thermoplastic material to form biaxially oriented shaped intermediates, followed by the heat-shrinking of the biaxially oriented intermediates onto a male form to produce articles of exacting dimensions and flat surfaces or sharply defined contours. Such thermoplastic articles include autoclavable, hot fillable, heat stable, transparent PET containers.

Abstract: Methods are provided for the design of backing dies utilized with front, decorative embossing dies for the simultaneous production and embossing of wood composite panels. The methods apply where more than one decorative pattern is embossed onto the wood composite panels during a single press cycle. The cross-sectional area or volume of the panels impressed with each different decorative pattern forms the basis for the methods of the design. Included are methods of forming wood composite panels using dies made according to the disclosed die design methods.

Abstract: A heated film die for the fabrication of plastic containers such as bags, envelopes, balloons, bladders, etc.. The die is an integrated sectionalized structure having independent, adjacent, electrically heated, temperature regulated, die sections which are maintained at different temperatures, for performing, simultaneously, two or more of operations such as, cutting, staking and forming, in plastic container fabrication. A lower temperature heat sink between adjacent die sections provides thermal isolation between the die sections.

Abstract: Apparatus and methods for the formation of biaxially oriented thermoplastic articles having flat surfaces or sharp contours, and the articles so produced. Such apparatus and methods relate to the heat-shrinking of biaxially oriented intermediates onto male forms to produce articles of exacting dimensions and flat surfaces or sharply defined contours. Such thermoplastic articles include autoclavable, heat fillable, heat stable, transparent PET containers.

Abstract: A method and apparatus for thermoforming 3-dimensional articles of chosen wall thickness dimensions from a polar polymer sheet. The polymer sheet is dielectrically heated, the heating being controlled to impress a predetermined thermal pattern on the sheet. The thermal pattern is selected in accordance with the amount of stretching to which each area of the sheet is subjected during the subsequent work-forming step, the areas subjected to greater stretching being heated to a lower temperature and vice versa. Thus, the stretching action is balanced and results in accurate control of the wall thickness of the final article.

Abstract: A method of and apparatus for moulding preformed material with a forming mould (1), tool, membrane or bag, in which as the material (A) is being moulded or shaped, a temperature controlled fluid is introduced at a sufficient pressure to act as a barrier between the material and the forming mould, tool, membrane or bag so that thickness of the article formed can be selectively controlled.

Abstract: A method for the operation of a thermoforming machine in which successive sections of a thermoforming web are formed includes the steps of continuously feeding a thermoformable web of plastics material into the entry of the thermoforming machine from an exit support roll of a substantially horizontal run portion of a conveyor, the exit support roll being movable forwardly in the direction of movement of the web and rearwardly in the opposite direction so as to respectively extend and retract the length of the horizontal run portion of the conveyor with the web flow speed at which the web is deposited initially on the conveyor and with the movement of vertically opposed male and female forming tools which are part of the thermoforming machine and which are able to advance and retract horizontally respectively in and against the web movement direction and to move vertically perpendicular to their horizontal movement.

Abstract: The apparatus includes advancement clamps which move two mutually facing films along an advancement direction on which the following are arranged in sequence: two welding half-molds, which by mutually welding the two films in preset regions define cells which are open toward a longitudinal edge of the films; two half-molds for heating the welded films; a cell forming station. Air injection nozzles, inserted between the two flaps of the films on the side of the above mentioned longitudinal edge, and two forming half-molds, in which forming cavities are defined at the cells, operate in the forming station. Divaricators for divaricating the two flaps of the films are provided proximate to the forming station so as to facilitate the insertion of the air injection nozzles.

Abstract: The described process comprises the following operating steps: an extrusion step in which the raw rubber is extruded in the form of a strip (7) from an appropriate machine (1); a winding step in which the rubber strip (7) is wound about a rotating drum (2); an insert application step in which steel insert pieces (16) are applied to the rubber layer wound about the rotating drum (2); a second winding step in which the rubber strip (7) is wound on the steel insert pieces (16); a coiling step in which a steel wire (4) is wound into spiral shape on the rubber layer wound about the rotating drum (2); a third winding step in which the rubber strip (7) is wound on the coiled steel wire (4) as far as a product in the form of a ring is achieved; a removal step in which the ring-shaped produce is removed from the drum (2); an introduction step in which the ring-shaped product is introduced into a mold; a forming and vulcanization step carried out on the product in the mold; an extraction step in which the ready track i

Abstract: Apparatus and methods for the formation of biaxially oriented thermoplastic articles having flat surfaces or sharp contours, along with the articles themselves. Such apparatus and method relate to the heat-shrinking of biaxially oriented intermediates onto male forms to produce articles of exacting dimensions and flat surfaces or sharply defined contours. Such thermoplastic articles include autoclaveable, hot fillable, heat stable, transparent PET containers.

Abstract: A multilayer container with a flange for sealing with a lid, wherein the thickness of the inner surface layer at the inner edge of the flange is thinner than that in the sealing area, is produced by a method wherein a circular portion of a multilayer sheet to be the flange is held at a certain pressure while the multilayer sheet is being thermoformed under specified molding conditions, with the other portion than the circular portion being stretched. Even a seal ring having an even surface serves as a means for sealing the resulting multilayer container with a lid while ensuring easy openability.

Abstract: An apparatus for deep drawing a bowl from a blank of deep-drawable plastic material is provided comprising deep drawing tools, and cooperating jaws including an outside heating jaw and a forward feed heating jaw. The deep drawing tools and cooperating jaws are movable relative to each other to advance a blank of deep-drawable material for preheating, forming, and deep drawing a bowl open at one end therefrom. The outside heating jaw includes at least one outside suction plate to retain the blank, and intermittently moves in a first direction into and out of cooperating relationship with the forward feed heating jaw. The deep drawing tool also intermittently moves parallel to the first direction into and out of cooperating relationship with the forward feed heating jaw. The forward feed heating jaw includes a plurality of main suction plates secured to a heatable carrier to retain and heat the blank as it advances thereon.

Abstract: A method is provided for fabricating resin-filled components, which comprise a multi-element arrangement of a thermoformed plastic sheet with a "second-surface" screen-printed graphic, which formed sheet can receive a light-directing apparatus, and the molded-resin is applied so as to secure the apparatus and provide stability to the overall structure or component. The method is particularly adapted with respect to the fabrication of graphic-display illuminated buttons for use within automotive vehicles.

Abstract: A retortable container has a wall of at least two co-formed laminas. This wall is highly impermeable to fluids selected from the group consisting of oxygen and aromatic vapors. The wall includes a first load-carrying lamina of a first plastic material. This load-carrying lamina has been formed without mechanical hysteresis in the melt phase by a thermal pressure forming apparatus to cause strengthening with orientation of the load-carrying lamina in at least one axis but without memory of its pre-melt phase shape. The wall also includes a second sealing lamina of a second plastic material. This second sealing lamina is coextensive with the first load-carrying lamina. Consequently, the container formed by the apparatus is retortable, i.e. it can withstand temperatures and pressures of a retort chamber without undergoing significant and permanent distortion.

Abstract: A method for curing fiber-reinforced resin matrix composite materials (22) includes the steps of providing a form (14) and positioning uncured composite material (22) on the form (14) substantially into a desired shape. The composite material (22) is then cured by providing a fluid bath (10) heated to a predetermined temperature, and heating the composite material (22) by immersing the positioned composite material (22) on the form (14) into the fluid bath (10) for a predetermined time. The predetermined time is sufficient to allow the composite material (22) to become cured and to heat the composite material (22) at a rate sufficient to provide resin flow prior to hardening. Compressive pressure is provided on the composite material (22) while it is immersed in the fluid bath (10).

Abstract: A web of thermoplastic material extruded directly into a set of tempering rolls is cooled on its upper and lower surfaces while the interior of the web is kept molten. The partially cooled web is fed onto a converyor on which it is fed to a thermoformer. The web remains on the conveyor until its surface layer in contact with the conveyor is reheated to a thermoformable temperature below that at which the web will stick to the conveyor. Apparatus for feeding a web of thermoplastic material from an extrusion to a thermoformer includes tempering rolls and conveyor means which can be adjusted in their relative positions and to control the length of conveyor means contacted by the web.