Abstract: A parison tube former utilizes a radial compression heater to heat a very specific portion of a preform tube for stretching. The heater has a plurality of compression dies that form a central cavity for receiving the preform tube. The working surfaces of the compression dies close down onto the outer surface of the preform tube to heat the tube via conduction, which more accurately and precisely heats the preform tube. A first stretched portion of the preform tube is produced by stretching the preform tube after heating. A second portion of the preform tube is then located within the central cavity and is also heated by the radial compression heater and stretched to produce a second stretched portion of the preform tube and an unexpanded portion of the preform tube, or balloon portion of the parison tube.

Abstract: Provided is an apparatus for transforming plastic preforms into plastic containers having at least one transforming station which has a blow molding device, within which the plastic preforms are able to be transformed into the plastic containers by application with a flowable medium, having an application device which applies the flowable medium to the plastic preforms and having a stretching device which has a rod-like body which is able to be introduced into the plastic preforms, in order to stretch the plastic preforms at least temporarily during their transforming process in the longitudinal direction thereof, wherein the stretching device has a drive device for moving the rod-like body as well as a control device for controlling the drive device and wherein the apparatus has a valve arrangement which controls the application of the plastic preforms with the flowable medium with at least two different pressure levels.

Abstract: There is provided a system, a method and preform suitable for executing liquid forming of the preform into a final-shaped container. The present technology includes various improvements to methods, apparatuses, and systems for forming final-shaped containers from preforms using a liquid destined to be contained in the final-shaped container.

Abstract: A stretch blow molding system (200) is provided. The stretch blow molding system comprises a cylinder (201) including a movable stretch rod (202) and a blow-mold valve (204). The blow-mold valve (204) comprises a first fluid port (204a) in fluid communication with a first pressurized fluid source (364a). The blow-mold valve (204) also includes a second fluid port (204b) in fluid communication with a second pressurized fluid source (364b). A third fluid port (204c) of the blow-mold valve is in fluid communication with the cylinder (201) and selectively in fluid communication with the first fluid port (204a) and the second fluid port (204b).

Abstract: The invention relates to a method for producing a plastic article and a blow molding tool for performing the method. The method comprises extruding an approximately tube-shaped preform, dividing the melt flow within the extrusion head or separating the extrudate exiting or already exited from the extrusion head, such that a preform having an approximately C-shaped cross section is obtained, forming the preform into a hollow part within a multipart blow molding tool using differential pressure, wherein an expansion and partial preforming of the preform first takes place with the blow molding tool partially closed, then in a further step at least one insert is inserted into the interior of the partially preformed article between the not completely closed blow molding tool and through the open side of the preform, and in a further step the blow molding tool is completely closed; wherein the article is completely formed, forming at least one at least partially circumferential pinch-off seam.

Abstract: A method and a device for recycling compressed gas where the compressed gas used in a compressed gas consumer, particularly a container blow-molding machine, is fed back into a compressed gas generator. In order to increase the recycling volume, the compressed gas from the compressed gas consumer is collected separately and fed back to at least a first and a second pressure range of the pressure generator separately according to pressure stages.

Abstract: A system for forming a container from a preform, wherein the preform has a finish and a support ring. The system includes a mold having a mold cavity defining an internal surface and adapted to accept the preform, a pressure system having an inlet and an outlet outputting fluid, a blow nozzle receiving the fluid from the pressure system and introducing the fluid at a pressure into the preform thereby expanding the preform toward the internal surface of the mold cavity and creating a resultant container. The system further includes a first seal engagement selectively engageable between the blow nozzle and the finish of the preform and a second seal engagement selectively engageable between the blow nozzle and an adjacent feature.

Abstract: An improved stretch rod tip having a hollowed area for receipt of a portion of a preform and at least a portion of a sprue during stretch blow molding of a container. Upon hardening of the container, the received portion of the preform becomes a protective dome over the received portion of the sprue that is at least partially internal to the container and that greatly reduces cracking, shearing, or other fracturing of the container due to a drop impact.

Abstract: In a blow moulding machine for the production of plastics material containers, during a blow mould procedure, the container to be expanded is supplied with blow moulding air from a first gas preparation device on the one hand or from a second gas preparation device on the other hand. During this procedure a cooling of the base of the container is additionally carried out.

Abstract: An apparatus and method for simultaneously forming and filling a plastic container is provided. A mold cavity defines an internal surface and is adapted to accept a preform. A pressure source includes an inlet and a piston-like device. The piston-like device is moveable in a first direction wherein liquid is drawn into the pressure source through the inlet and in a second direction wherein the liquid is urged toward the preform. A blow nozzle may be adapted to receive the liquid from the pressure source and transfer the liquid at high pressure into the preform thereby urging the preform to expand toward the internal surface of the mold cavity and creating a resultant container. The liquid remains within the container as an end product.

Abstract: The mould carrier unit for manufacturing containers by a stretch blow-moulding operation of preforms (3) arranged in moulds (2), comprises: on the one hand, a stretching rod (10) borne by a slide (13) which is mobile between an inactive position and an active position where its free end reaches the bottom of said mould (2), on the other hand, a nozzle (15) comprising a fixed body (16) extended by a bell (20), which is mobile under the action of appropriate means for passing from an inactive position where its free edge (25) is held substantially at the same level as the free end (11) of the stretching rod (10) to an active position where it is sealingly applied against the inlet surface (4) of the mould (2), to close the circuit of the blowing fluid, and said bell (20) comprises a bar (21) provided with a stop (23), which stop (23) cooperates with a support (24) formed on said slide (13) to permit said bell (20) to pass from its active position to the inactive position with the same law of motion as sa

Abstract: Process for manufacturing a plastic hollow body, the process comprising the following steps: a) a tubular stream of molten plastic is extruded; b) this stream is taken up by means of a tensioning device; c) a transverse cut is made in this stream so as to create a parison having one free edge that is not taken up by the tensioning device; d) the parison is moved relative to the tensioning device so that the free edge of the parison is also taken up by the tensioning device; and e) at least one longitudinal cut is made in the parison over its entire length. Equipment suitable for implementing this process.

Abstract: A process for producing containers includes the steps of providing a container having a shaping region, the shaping region comprising a thermoplastic material; applying an ink to the shaping region; discretely heating the shaping region to a shaping temperature; and discretely shaping the shaping region to take a desired three dimensional shape. A system for producing containers having three dimensional decorations, and containers having three dimensional decorations, are also disclosed.

Abstract: A device for producing a tubular object from thermoplastic material includes a die, a plunger, and a withdrawal unit. The movements of the withdrawal unit, plunger and die body are controlled such that the movement of the withdrawal unit is carried out according to a freely adjustable velocity profile over the path of the withdrawal unit. Movement of the plunger is carried out according to a freely adjustable velocity profile over the plunger path and movement of the die body is carried out according to a freely adjustable position profile over the path of the withdrawal unit or plunger. In this manner, the wall thickness of the tubular object may be adjusted with high accuracy over its length.

Abstract: Process for manufacturing a plastic hollow body, the process comprising the following steps: a) a tubular stream of molten plastic is extruded; b) this stream is taken up by means of a tensioning device; c) a transverse cut is made in this stream so as to create a parison having one free edge that is not taken up by the tensioning device; d) the parison is moved relative to the tensioning device so that the free edge of the parison is also taken up by the tensioning device; and e) at least one longitudinal cut is made in the parison over its entire length. Equipment suitable for implementing this process.

Abstract: A process and a device for the manufacture of a hollow body, particularly of a heat-resistant hollow body, which is molded out of a heated preform of thermoplastic plastic in a contoured blow mold through the introduction of a first medium into the preform, which medium is stored in a first medium storage unit and is under a pressure (p1) (preblowing phase), and the more or less simultaneous stretching of the hollow body through a stretching rod and the introduction of a second medium in the hollow body, which medium is stored in a second medium storage unit and the pressure of which (p2) is higher than the pressure of the first medium (p1) (final blowing phase), and which is cooled by a third medium, which is medium stored in a third medium storage unit (rinsing phase), whereby the preblowing medium is under a pressure of approximately 2-20 bar, the final blowing medium is under a pressure of approximately 15-45 bar, and the cooling medium is under a pressure of approximately 30-45 bar.

Abstract: A device for molding a container from a thermoplastic material in which a heated parison is pre-blown by supplying low-pressure blowing air from a low-pressure air supply and then the blow molding is completed by subsequent supply of high-pressure blowing air and in which the high-pressure blowing air flowing out of the container that has been completely blow molded is supplied to the low-pressure air supply via a reversing mechanism during a transitional phase. A pressure monitoring is performed in the area of the low-pressure air supply and in which, after the transitional phase, the container is vented with respect to an ambient pressure whereby the pressure in the low-pressure air supply is controlled by varying the duration of the transitional phase.

Abstract: Disclosed herein is a mold module from a set of substantially structurally independent mold modules of at least one of a first mold assembly or a second mold assembly. The first mold assembly and the second mold assembly for accepting, in use, a plurality of first mold inserts and second mold inserts, respectively, to define, in use, a plurality of substantially identical molding cavities therebetween. A subset of at least one of the first mold inserts or the second mold inserts being accepted in the mold module.

Abstract: The present invention relates to a mold device having a combination of molds for stretch blow molding, comprising a main blow mold 5, installed on a pair of platens 2 by being separated into split molds 5a, a pre-blow mold 10, attached to a lifting device 11 under the area between the split molds 5a, and movable in and out from the area between the split mold 5a, a neck mold 7, which is fitted into the pre-blow mold 10 and main blow mold 5 respectively, a blow core 20, which is fitted in to the neck mold 7, and a stretch rod. The pre-blow mold 10 comprises a cylindrical member having an open end on the upper portion, which is fitted into the neck mold 7. A bottom mold 8 of the main blow mold 5 is installed in the bottom portion of the split mold 5a by being separated into split bottom molds 8a. Lifting cylinders 9 are placed under the both of the split bottom molds 8a in order to make the bottom mold 8 movable in and out from the bottom portion of a cavity.

Abstract: A forced exhaust pipe is connected to an exhaust pipe connected with a cross head so that a negative pressure may be formed within an air passage so as to effect rapid control of air pressure (amount) within a parison, thereby stabilizing the air pressure within the parison. A parison stabilizing method and a system therefor for use in a hollow formation molding machine, according to the present invention, are so formed that a forced air-discharge is carried out through an exhaust pipe connected with the air passage formed within the cross head, so that a negative pressure is formed within the air passage. In this way, the above-mentioned system can effect quick control of an air pressure (amount) within the prison during a pre-blowing treatment, shorten a time period necessary for determining molding conditions, without having to increase the inner diameter of the air passage.

Abstract: The invention concerns a method for making plastic tubes, whereby a tube blank (Te) brought to a temperature close to molecular orientation temperature is subjected to a bi-axial drawing, by radial expansion of the tube blank inside a forming shaft (2), with formation of a contraction cavity at one end of the tube, by controlled displacement of this contraction cavity to the other end of the tube, and by longitudinal drawing. The radial expansion is carried out in at least two phases, viz. a first phase during which the tube blank (Te) is inflated to an intermediate diameter (Di) determined by a double-walled envelope (21), introduced into the forming shaft (2), with circulation of a hot fluid between the two walls of the envelope (21), and then the envelope is gradually removed from the forming shaft (2) to enable, during a second phase, the radial expansion of the plastic tube up to an internal diameter of the forming shaft (2), and its longitudinal drawing.

Abstract: The process and device are intended for controlling the molding of a container during the manufacture of containers from a thermoplastic material. At least two previously injection-molded preforms are temperature-treated and delivered in succession to at least one blow station for blow molding of the preforms into containers. In order to compensate for nonuniform temperature distribution in the material of the preforms relative to one another, at least one blow parameter during molding of the preforms into containers is specified in a fashion that differs from one to the next. The differing specification is made in such a manner as to compensate for the nonuniform temperature distribution so that containers with approximately identical spatial distribution of wall material, orientation properties, and crystallization characteristics exist when the blow-molding process is finished.

Abstract: A container obtained by biaxially stretch-blow-molding a resin. Except the mouth-and-neck portion, vicinities thereof and the center of the bottom portion, the container as a whole is reduced in thickness under a highly drawing condition without accompanied by whitening, and a portion constituting the bottom valley portions has an yielding load of not smaller than 25 kg/cm at 70.degree. C. The container exhibits excellent heat resistance, pressure resistance, shock resistance as well as self-standing ability.

Abstract: The apparatus has means (10, 11) for placing a parison (12) between two portions of a blow mold (14, 16). The parison (12) is put on the head of a blowpipe (32) placed between the two mold portions. On closing the mold, the top end of the parison is pinched in a top region of the mold and the bottom end of the parison is clamped against the blowpipe (32). A pre-blow step is performed on the parison to obtain an envelope which is then turned over by moving the blowpipe (32) upwards together with a turnover piston (34, 36), prior to performing a final blow step.

Abstract: A heat-resistant container molding apparatus and method which are compact and inexpensive and can reliably increase the crystallinity, reduce the residual stress in a container filled with a hot content such as thermally sterilized fruit juice, and prevent a thermal deformation with improved container stability at a raised temperature. The apparatus has a receiving and removing unit for receiving primary moldings obtained by blow-molding preforms and for removing final products, a heat treatment section for heating the primary moldings by bringing the primary moldings into contact with the inner wall of a heat treatment mold while pressurizing the interior of the primary moldings within the heat treatment mold, a final molding section for blow molding intermittent moldings into final products within a final blow mold, and a rotary plate, neck support fixing plate and neck support member for conveying the moldings through the receiving and removing unit, heat treatment section and final molding section.

Abstract: Multichamber tubular containers are made by extrusion or injection stretch blow molding. The containers usually will have two or three chambers and one or more web walls. The web walls are relatively rigid as formed. The web walls must be stretched laterally to increase their flexibility which is needed for the uniform dispensing of product from the tubular chambers. The webs can be stretched mechanically by the rotation of rods, such as stretch rods, or pneumatically by a differential gas pressure in the chambers while the webs are at or near the glass transition temperature and can flow. The web walls for a circular tubular container can be stretched up to about one-half the diameter of the tubular container.

Abstract: A system for moulding containers in thermoformable and heat-weldable material. The system includes a heating and welding station and a forming and shape-stabilizing station, with at least one welding and forming station in-between, producing progressive forming and shape-stabilizing of the containers.

Abstract: There is provided a method of molding a large container including the steps of preparing a preform from an injection-molded, thick-wall, closed-end parison by repeatedly and intermittently applying an air blow pressure to the parison and releasing the air blow pressure therefrom, and stretch blow molding the preform to a thin-wall large container. The closed-end parison is released from a mold immediately after a skin layer, keeping a parison shape, is formed on the surface of the closed-end parison having a high inner temperature, and is then molded to a preform with a preform mold heated to a predetermined temperature, while the surface temperature of the parison is increased by the inner temperature. The preform is kept at a stretch blow molding temperature and is stretch blow molded into a blow mold to produce a large container.

Abstract: A fluid supply apparatus for a blow mold, which includes a control valve having multiple positions for alternatively supplying fluid to the blow mold from a fluid supply and a metering chamber. The control valve has a further position configured to fill the metering chamber with fluid, and empty the blow mold chamber into an exhaust conduit. The apparatus is useful for performing pulse blow inflations at a high-strain rate in order to increase the crystallinity level in the body of a container.

Abstract: An apparatus for annealing and heat treating biaxially oriented articles is disclosed, particularly blow molded articles prepared from preforms which are simultaneously annealed using warm fluid in a first segmented mold. The blown article is transferred to a second, larger mold where the article is pressurized against the mold to form the final container design and to heat treat at least a portion of the bottle wall to improve crystallinity and strength. Portions of the mold, used to form and anneal the articles, are temperature controlled at various temperatures by passing warm water through conduits in the neck-shoulder portion and body portion of the mold and cold water through the bottom and shoulder portion of the mold to bring the temperature of the article wall to about 65.degree. C. to 95.degree. C. for PET bottles. The second mold is up to 10% larger in volume and preferably employs resistance heating to heat treat the side wall to 110.degree. C. to 220.degree. C.

Abstract: Apparatus for forming a lightweight plastic bottle having a body and an integral handle includes pre-blowing a tubular parison positioned between partible blow mold sections, closing the blow mold sections to compression mold the handle and blowing the parison to form the body integral with the handle and a line of juncture between the body and the handle.

Abstract: A plastic container, particularly suited for returnable and refillable PET carbonated beverage bottles, having an enhanced level of crystallinity in the sidewall but maintaining a very low level of crystallinity in the base. The container can withstand higher caustic wash temperatures and exhibits reduced flavor carryover from one product to another. The container is formed from a preform, wherein a sidewall-forming section of the preform is initially expanded and then heated to contract and crystallize the same before being reexpanded, and a base-forming portion of the preform is shielded from the heat treatment and expanded either before or after the heat treatment.

Abstract: Apparatus and methods for forming dilatation balloons and catheters including same are provided. The balloons are fabricated of a material such as a nylon or a polyamide material, and they have been inflated, non-distended working profile as well as a stretched inflated profile which is achieved by applying pressure through a dilation catheter or the like that is in excess of that needed to achieve the inflated, non-distended profile and which is adequate to effect dilation or the like up to a maximum pre-bursting pressure application. The maximum pre-bursting size of the balloon can be tailored depending upon the needs of the particular balloon within a wide range of possible maximum pre-bursting sizes. The apparatus and methods facilitate fabrication of the balloons which are subjected to longitudinal elongation and radial expansion.

Abstract: Apparatus includes a blow mold, a holding device for holding the parison within the blow mold, a blow device for forming a blown article in the blow mold and a stretch rod for stretching the parison movable in the holding device. A device is provided for determining the position of the stretch rod in the holding device channel and for synchronizing the transmission of high pressure fluid to the parison based on the position of the stretch rod.

Abstract: A process for the manufacture of a polyethylene terephthalate (PET) container from a hollow amorphous PET preform which includes an open end and a closed end, the open end forming a neck section having dimensions already conformed to its final size and shape, the container being able to withstand relatively severe thermal conditions encountered when the container is filled with a hot liquid, without appreciable deformation, including the steps of: a) rapidly heating only the body of the PET preform, exclusive of the neck section, to a temperature at which subsequent longitudinal and transverse stretching cause no stresses in the PET; b) transferring the hot preform from step (a) to a mold whose walls are maintained at a temperature lower than the temperature of the hot preform body; c) longitudinally stretching the preform body while simultaneously transversely expanding it by blow-molding using a pressurized fluid so as to mold the preform body to the shape of the mold cavity; d) rapidly evacuating the press

Abstract: A parison stick is used with an injection-blow molding machine for injection-blow molding of a hollow article of plastic material from a parison of this plastic material. The stick has three axially-contiguous portions. The portion (A) connects the parison stick to the injection-blow molding machine. The portion (B) positions the parison stick in the wall of a mold within the machine. The portion (C) terminates in the cavity of the mold and includes distinctly and axially-spaced first and second openings through which gas blows and inflates a parison previously injected around this portion. The openings are connected to a gas-feed chamber via at least one channel. The parison stick further includes at least one obturator connected to an actuator which is controlled by a control member of the machine.

Abstract: Apparatus and methods for forming dilatation balloons and catheters including same are provided. The balloons are fabricated of a biaxially orientable material such as a nylon or a polyamide material, and they have an inflated, non-distended working profile as well as a stretched inflated profile which is achieved by applying pressure through a dilatation catheter or the like that is in excess of that needed to achieve the inflated, non-distended profile and which is adequate to effect dilatation or the like up to a maximum pre-busting pressure application. The maximum pre-busting size of the balloon can be tailored depending upon the needs of the particular balloon within a wide range of possible maximum pre-busting sizes. The apparatus and methods facilitate fabrication of the balloons which are subjected to longitudinal elongation or axial orientation and biaxial or radial orientation.

Abstract: Apparatus and methods for forming dilatation balloons and catheters including same are provided. The balloons are fabricated of a biaxially orientable material such as a nylon or a polyamide material, and they have an inflated, non-distended working profile as well as a stretched inflated profile which is achieved by applying pressure through a dilatation catheter or the like that is in excess of that needed to achieve the inflated, non-distended profile and which is adequate to effect dilatation or the like up to a maximum pre-bursting pressure application. The maximum pre-bursting size of the balloon can be tailored depending upon the needs of the particular balloon within a wide range of possible maximum pre-bursting sizes. The apparatus and methods facilitate fabrication of the balloons which are subjected to longitudinal elongation or axial orientation and biaxial or radial orientation.

Abstract: A flat container may be produced by extruding a molten resin to form a parison, closing the bottom of the parison, preblowing the parison such that the inner surfaces do not contact together, drafting the parison in a molten state, expanding the parison with the outer edge of the parison extending beyond that of the cavity of a mold, pinching the expanded parison with the mold to fuse the outer edge portions together along the outer edge of the cavity, and forcing a pressurized fluid into the parison pinched by the mold so that the parison is shaped in close contact with the inside surfaces of the mold cavity.

Abstract: Apparatus and methods for forming dilatation balloons and catheters including same are provided. The balloons are fabricated of a biaxially orientable material such as a nylon or a polyamide material, and they have an inflated, non-distended working profile as well as a stretched inflated profile which is achieved by applying pressure through a dilatation catheter or the like that is in excess of that needed to achieve the inflated, non-distended profile and which is adequate to effect dilatation or the like up to a maximum pre-bursting pressure application. The maximum pre-bursting size of the balloon can be tailored depending upon the needs of the particular balloon within a wide range of possible maximum pre-bursting sizes. The apparatus and methods facilitate fabrication of the balloons which are subjected to longitudinal elongation or axial orientation and biaxial or radial orientation.

Abstract: A method of making flat bottles with flat or concave bottom by free extrusion of a plastic tube includes blowing of an intermediate form with circular cross section and shaping the latter essentially mechanically to the flat bottle at simultaneous final blowing for achieving clean radii. It is essential that the intermediate form is blown at a length corresponding to about the height of the flat bottle, with a circumference in the body area of -1 to about -10%, however, in the bottom near area of the side walls from 0 to about +15%, with regard to the corresponding circumference of the flat bottle. The radius of curvature at the junction from the body wall to the bottom should correspond to about the radius of curvature at the junction from the body wall of the broad side of the flat bottle to its bottom. The bottom part corresponding to the pinched end of the tube is pinched off during shaping.

Abstract: A method for making a partially crystalline, biaxially oriented heat set hollow plastic container from a hollow poly(ethylene) terephthalate parison having an open end and a closed end comprising engaging the open end of a plastic parison which is at a temperature within its molecular orientation temperature range, enclosing a hot mold about the hot parison, the mold being at heat setting temperature, expanding the plastic parison within the hot mold by internal pressurization to induce biaxial orientation of the plastic parison and force the plastic parison into intimate contact and conformance with the hot mold and to maintain contact by such internal pressurization between the mold and the biaxially oriented container for a time sufficient to induce partial crystallization in the biaxially oriented container, maintaining a lower internal pressurization of the container to prevent significant shrinkage, opening the hot mold while maintaining engagement of the open end of the blown hollow container, enclosin

Abstract: Process for producing a blown hollow vessel having an external annular projection integrally formed from the vessel wall in the blowing process. The vessel is formed initially in a mold having a reduced contour in the wall regions adjoining the annular projection. The vessel thus formed is then placed in a mold having the desired finished contour and blown to its final shape. In this manner, the vessel wall adjoining the annular projection is stretched and the inner surface of the vessel wall is smoothed in the area where the annular projection was formed.

Abstract: A method for making a partially crystalline, biaxially oriented heat set hollow plastic container from a hollow parison having an open end and a closed end comprising engaging the open end of a plastic parison which is at a temperature within its molecular orientation temperature range, positioning a mold base in axial alignment with said engaged hot parison, enclosing a hot mold about the mold base, the mold being at heat setting temperature, expanding the plastic parison within the hot mold and mold base by internal pressurization to induce biaxial orientation of the plastic parison and force the plastic parison into intimate contact and conformance with the hot mold and to maintain contact by such internal pressurization between the mold and the biaxially oriented container for a time sufficient to induce partial crystallization in the biaxially oriented container, lowering the internal pressure in the container, opening the hot mold while maintaining engagement of the open end and engagement of the mold b

Abstract: A temperature control blow molding equipment which has a temperature control mold and a blow mold on one seat body and which is used in an injection stretch blow molding machine comprising a disk-like moving plate intermittently rotatably disposed above a base disk, a plurality of neck molds provided at regular intervals under the carrying plate, and operation zones disposed at stop positions of the neck molds, the operation zones being necessary for a series of treatments from an injection molding of a parison to a removal of a molded article.

Abstract: A method for manufacturing hollow bodies from thermoplastic material by making hollow body-shaped preforms provided with opening nipples, which during a subsequent processing operation are reduced to the final shape after converting at least a part of their wall into deformable condition, whereby the forming-out takes place in at least two stages.

Abstract: Expanding the parison while the mold side parts defining the walls of the blow-molding chamber, one part per wall, are moved to mold closed positions causes flash to be pinched between each mold part and provides good wall thickness near the edges of the final product.

Abstract: A method and a device for production of a temperature-stable, biaxially oriented container of thermoplastic material. In a first moulding stage a blank (40) is placed in a blow mould (12) after which a mandrel (15) extends the blank in its axial direction to a length exceeding the axial length of the future container. The length of the stretched material, in an axial section through the stretched blank, is then reduced at a predetermined temperature, and the reduction being made to a profile length substantially agreeing with the profile length for corresponding material portions in an axial section through the future container. In a second moulding stage the stretched blank is expanded to abut against the walls of the mould. The expansion takes place at a point in time for and/or at a speed allowing the reduction of the length of the stretched material, due to shrinkage to have time to be concluded before the material comes into contact with the walls of the mould.

Abstract: A blow-molded thermoplastic body is made by a method which comprises the following steps: inflating a hollow parison within a mold cavity for causing the parison to expand and conform to inner wall surfaces defining the mold cavity, whereby the blow-molded body is shaped; further inflating the blow-molded body within the mold cavity for causing a wall portion of the body to expand beyond the mold cavity into a port cavity communicating with the mold cavity thereby reducing the thickness of the wall portion; applying a counter pressure on an outer face of the wall portion for moving the wall portion back in the direction of the mold cavity against an inflating pressure prevailing within the blow-molded body, whereby connecting portions attaching the wall portion to the blow-molded body are reduced in thickness; and discontinuing the application of the counter pressure for allowing the wall portion to be driven anew away from the mold cavity into the port cavity by the inflating pressure.

Abstract: In blow molding an article with a reverse fold, a profiled bar is positioned where the parting line of the mold is to be when the mold is closed. The bar provides a reverse fold in the plastic article during a pre-blow step. In operation, a pre-pinched parison is formed adjacent the bar and as the mold begins to close a small amount of pre-blow air is introduced into the parison folding it against and over the bar. After the mold is closed, blow air is introduced to form the part. A complex part with good wall distribution of material can be obtained by this method.