Abstract: This invention relates to a process of producing sheets from thermoplastic resins and a screw used therefor. The resin extruder includes a cylinder and the screw. The resin is passed through a feeding section, a compressing section, a metering section, a mixing section, a shearing section and a stress relaxing section, which are successively positioned from a resin feeding side to a resin extruding side, and a molten film-shaped resin is extruded, and this film-shaped resin is passed in a co-current direction with cooling water and is cooled.

Abstract: A method for manufacturing molded products of polyethylene terephthalate by injection molding or extrusion molding a material containing polyethylene terephthalate as the principal component characterized by using virgin and/or waste polyethylene terephthalate of average molecular weight of more than 10000 to which polymer such as nylon and/or inorganic fillers can be added as required, and molding said material under the following molding conditions by a general type or vent type molding machine:(a) Control of a temperature of a cylinder of the molding machine in the range of melting temperature of resin plus/minus 35.degree. C., and(b) Control of the staying hour of resin in the cylinder to be within 15 minutes.

Abstract: A method of extruding a ceramic batch supplied from a vacuum auger machine into a formed body by a plunger molding machine, included the steps of loosening and crushing a supplied ceramic batch in the vacuum auger machine, extruding the loosened and crushed ceramic batch from the vacuum auger machine into a formed columnar body which is of a size able to be inserted into a cylinder of the plunger molding machine, and extruding the formed columnar body from the plunger molding machine to form a formed body of a predetermined shape. An apparatus for extruding a ceramic batch includes a vacuum auger machine having of a vacuum kneading section for kneading a ceramic material to produce a ceramic batch, a columnar body forming section for forming the kneaded ceramic material into a columnar body, and a batch transfer section having an auger for transferring the ceramic batch to the columnar body forming section.

Abstract: A device for expelling the gas liberated within a viscous-material treating apparatus such as a kneader, an extruder or the like. The device basically consists of a cone-shaped rotor and a cone-shaped cover member covering the rotor. The cone-shaped rotor is provided with volute protrusions on its coned surface, while the cone-shaped cover member is provided with a gas exhaust orifice to which a vacuum system is to be connected. With the cone-shaped rotor kept rotating, the volute protrusions act so as to prevent the viscous material from being swallowed up together with the liberated gas to be pumped out.

Abstract: In a vent type injection molding machine of the type comprising a heating cylinder, injection nozzle means having a vent port and connected to the front end of the heating cylinder and a reciprocatable screw for metering a predetermined quantity of resin to be injected, the injection nozzle means comprises a first injection nozzle connected to the heating cylinder, a second injection nozzle coaxial with the first injection nozzle, a spring for urging the second injection nozzle against a stationary metal mold and a housing surrounding the first and second injection nozzles. The vent port is provided through the housing at a point communicating with a space in the housing between the first and second injection nozzles.

Abstract: The invention relates to a process for degassing and pelletizing polyolefin particles produced by a gas phase polymerization. The polyolefin particles are submitted to a primary degassing, preferably at the outlet of a reactor for catalytic polymerization in the gas phase. Then the polyolefin particles are subjected to a secondary degassing step comprising agitating the particles by a mechanical stirrer and converting the mechanical energy therefrom into heat such that the temperature of the particles is brought to between 80.degree. and 120.degree. C. which is close to minimum sintering temperature Ts so that the polyolefin particles are substantially freed from the gases accompanying them. The heated degassed polyolefin particles are then pelletized in an extruder of a pelleting unit.

Abstract: A kneading machine with a charging opening leading to a kneading chamber, in which two axially parallel kneading tools can be driven in opposite directions at different rotational speeds, has at least three such kneading chambers which are disposed next to each other and an aperture which connects their internal spaces. The material to be kneaded can be conveyed through this aperture, which extends transversely of the shafts of the kneading tools from one kneading chamber to the next, so that the material is continuously treated until it reaches in the last kneading chamber an evacuating opening and preferably an evacuating worm which is mounted at such location and by means of which the material is ultimately evacuated from the machine. In this manner, the advantages of a kneading machine with shafts for kneading tools which are journalled at both ends are combined with the advantages of continuous treatment of the material to be kneaded.

Abstract: The present disclosure is directed to a method of injection molding PVC products from powdered raw material, while employing an injection molding machine having a plasticizing unit having a rotary screw and a rotary screw and an injection unit having a screw which both rotates and reciprocates. The powdered raw material is subjected firstly to a prejellifying treatment during forced transportation through the plasticizing unit in which it is heated and brought to agglomerate in a relatively short time and the agglomerate is subjected to a vacuum after the prejellifying treatment and its introduction into the injection unit at an absolute pressure of less than 50 kPa.

Abstract: A mixing apparatus for mixing thermoplastic compounds wherein the mixing body has a pair of parallel chambers with a pair of rotors rotatably journaled therein. Such mixer has at least one bore communicating the parallel chambers with atmosphere to vent gases from the central bore. A rotatable screw is mounted in the bore which upon rotation continuously feeds the mixed thermoplastic material back into the chambers but allows the gases generated to be vented out of such bore.

Abstract: A structure of an extruding apparatus for extruding a synthetic resin, including a first extruder and a second extruder having a vent hole, is disclosed. The extruding apparatus includes: a first extruder; and a second extruder having a cylinder with a vent hole, a supply port provided at the proximal end of the cylinder, and connected to a discharge port of the first extruder, a distribution/supply means provided inside the cylinder, having a plurality of passages for fluidically connecting the supply port and a space inside the cylinder, and distributing and supplying a molding material supplied to the supply port into the cylinder, a discharge port provided at the distal end of the cylinder, a screw shaft arranged inside the cylinder, and a motor for driving the screw shaft. An airtight vacuum chamber connected to the vacuum pump is mounted on an outer portion of the vent hole.

Abstract: The invention relates to a method for the manufacture of molding materials containing polyphenylene ether (PPE) and to the materials obtained according to this method. Molten PPE containing at least 0.1% volatile components is degasified until it reaches a residual content of volatile components of less than 500 ppm. Subsequently, additional molten polymers and/or additives are added to this molten mass at the lowest possible temperature and both components are mixed.

Abstract: A degassing device on a worm extruder having a worm housing accomodating the worm or worms and provided with at least one degassing passage opening into the worm chamber of the housing is provided with a return delivery device for material which has penetrated from the worm chamber into the degassing passage. The free surface (evaporation area) of the extruder material within the degassing passage amounts to more than about 40% of the degassing passage cross-section, and the smallest gas passage cross-section of the return delivery device amounts to at least about 0.1 times, the degassing passage cross-section. Especially in the case of pasty material this reliably prevents a blockage of the degassing passage by the material processed in the worm extruder.

Abstract: A process and apparatus for degassing high-boiling liquids, especially polymer melts and solutions, to remove low-boiling liquids and gases as impurities by feeding the polymer melt or similar high-boiling liquid under expansion into the feed chamber of a gear wheel pump to flow downwardly and only partially fill this feed chamber, preferably so as to form a thin layer or pool of the melt atop the upper crown surfaces of the gear wheels. The impurities are withdrawn separately through a suction outlet and the liquid level of the melt is preset and maintained by suitable regulating apparatus adapted to control the speed of the gear wheels and/or the speed at which melt is delivered into the pump feed chamber.

Abstract: An improved process and apparatus for producing a uniform organic-filler-blended resin composition from a mixed material of a thermoplastic resin and a coarse organic filler raw material such as waste paper by the use of a specified extruder, without the necessity of fine-grinding of the organic filler raw material prior to feeding it into the extruder are provided, which process and apparatus are characterized by providing many projections and grooves surrounding them on the surface of an intermediate part of the screw in the extruder and specifying the size of the gap between the outer surface of the screw part and the inner surface of the cylinder opposed thereto.

Abstract: The invention relates to a device and a process for recovering polymer from a melt or solution containing volatile components. The device consists of an evaporating zone passing, via a metering device, which can function also as a pressure-reducing device, into a devolatilizing extruder. The metering and pressure-reducing device makes it possible also to process highly viscous melts of high-molecular polymers and to fill the extruder screws incompletely so that substantial devolatilization is realized in the extruder.

Abstract: A method for manufacturing molded products of polyethylene terephthalate by injection molding a material containing polyethylene terephthalate as the principal component characterized by using virgin and/or waste polyethylene terephthalate of average molecular weight of more than 10000 to which polymer such as nylon and/or inorganic fillers can be added as required, and molding said material under the following molding conditions by a general type or vent type molding machine:(a) Control of a temperature of a cylinder of the molding machine in the range of melting temperature of resin plus/minus 35.degree. C., and(b) Control of the staying hour of resin in the cylinder to be within 15 minutes.

Abstract: A method of extruding thermoplastic resin by use of an extruder, wherein the thermoplastic resin is continuously passed through a compression moderating type resin feeding-melting section, a resin flow disturbing section and a resin stress relaxing section, and extruded through a die. In an apparatus for working this method, a helical screw of the extruder is provided with the resin feeding-melting section, the resin flow disturbing section and a transfer section for relaxing the resin stress.

Abstract: Apparatus and method are provided in a system for continuously feeding disparate materials into a compounding extruder for the inline sheet extrusion of a highly filled thermoplastic material having at least about 65 percent by weight of filler. The apparatus and method of the present invention are particularly suitable in conjunction with the continuous lamination of the inline sheet extruder product with carpet.

Abstract: Dough is moved by a screw conveyor (28) in the bottom of a hopper (12) through a hopper discharge opening (25) and through a discharge conduit (14). A wedge-shaped shield (58) is mounted in the lower portion of the hopper over the screw conveyor (28) and divides the dough moving down the hopper and guides the dough to opposite side of the screw conveyor and maintains an air passage (92) in the dough over the screw conveyor and in communication with the discharge conduit (14). A partial vacuum is drawn in the air passage (92) to evacuate gas from the dough.

Abstract: Filled silicone rubber bases can be prepared without plasticizer by passing all of the filler together with from 30 to 100 percent of the total weight of the polyorganosiloxane ingredient of the base through the first kneading section of a compounding extruder and adding my remaining polyorganosiloxane before passing the composition through a second kneading section of the compounding extruder. The two kneading sections are maintained at temperatures of from 200.degree. to 300.degree. C.

Abstract: A device is described which eliminates the pre-drying of particulate plastic prior to processing by an extrusion or injection molding machine. A tubular guide member directs particulate plastic under gravity into the feed inlet of the machine. During delivery, the temperature of the particulate plastic is raised with heated air flows to between about 150.degree.-200.degree. F. Suction is applied to the feed inlet of the machine to remove volatiles (primarily water) released when the temperature of the particulate plastic is increased by contact with the heated barrel and screwdriver of a machine. Temperature and suction controls permit selection of operating temperature and suction levels that ensure removal of volatiles prior to any extensive plasticization and transfer along the barrel which would otherwise preclude proper removal of volatiles.

Abstract: A method and apparatus for removing hot volatiles and moisture from particulate plastic material being fed for injection or extrusion molding by a plasticizing screw which rotates in a heated barrel. Flow control means, such as a conveying screw or rotary valve, drop the particulate material downward through a vertical feed passage extending to an opening in the barrel. At the same time, suction is applied to remove hot volatiles which are released through the opening in the barrel as the particulate plastic material is gradually melted as it is compressed by the screw. The rate of feed of the particulate material is restricted so that the barrel of the plasticizing screw is only partially filled near the opening, thereby improving the withdrawal of the gases from the barrel. The incoming particulate material is preheated by a continuous flow of hot air through it as it passes through a tubular guide member.

Abstract: In a process of making sheet material comprising a substrate web of synthetic thermoplastic material and an adhesive layer consisting of a non-crosslinkable elastomer the elastomeric material is heated above its devolatilization temperature by a feed screw of a screw extruder and is devolatilized through venting means (vent opening and vacuum pump 21) and is subsequently pressurized by a booster 7 to a pressure which is sufficient to overcome the backpressure applied by the succeeding blow head.

Abstract: An improved process for incorporating glass fibers into a thermoplastic synthetic resin wherein the glass fibers are continuously mixed with a molten thermoplastic synthetic resin and the resulting mixture is shaped into a desired article, involves preheating the glass fibers to a temperature not more than the melting point of the synthetic resin, feeding the preheated glass fibers and the molten synthetic resin separately to a premixing chamber, intermixing the resin and fibers within the chamber and thereafter introducing the resultant premix continously and directly into a two-stage degasifying screw-type extruder for effecting further homogenization of the premix and for extruding the desired article. The two-stage degasifying screw-type extruder used for carrying out this process is provided with a screw having a constant screw pitch in the two stages and in each stage with a low pressure zone and a high pressure zone in succession.

Abstract: This invention relates to a method and apparatus for removing hot volatiles and moisture from particulate plastic material being fed for injection or extrusion molding by a plasticizing screw which rotates in a heated barrel. Flow control means, such as a conveying screw or rotary valve, drop the particulate material downward through a vertical feed passage extending to an opening in the barrel. At the same time, suction is applied to remove hot volatiles which are released through the opening in the barrel as the particulate plastic material is gradually melted as it is compressed by the screw. The rate of feed of the particulate material is restricted so that the barrel of the plasticizing screw is only partially filled near the opening, thereby improving the withdrawal of the gases from the barrel. The incoming particulate material is preheated by a continuous flow of hot air through it as it passes through a tubular guide member.

Abstract: A process for removing volatile constituents from polymer melts or pastes, wherein the polymer or paste containing the volatile constituents is passed, with continuous formation of fresh surfaces, through one or more zones in which the volatile constituents evaporate, and the volatile constituents are removed from the zone or zones in which they evaporate through, in each case, a plurality of porous orifices, and an apparatus for carrying out said process.

Abstract: A screw- or worm-type degassing extrusion device wherein a pin region is provided to increase throughput of the mixture to be extruded, such increased throughput being maintained and utilized to provide an adequate pressure for, for example, a tool by locating the pin region immediately upstream of the degassing region and by increasing the diameter of the cylinder or barrel of the extrusion device in the degassing and discharge regions compared with its diameter in the pin region.

Abstract: The disclosure relates to a ram extruder including an extruder barrel having an extrusion die at one end and a hydraulic ram at the other end having a piston which is advanced along the barrel by the ram to displace material in the barrel through the extrusion die. To facilitate loading of the barrel a loading port is provided in the side of the barrel adjacent said other end of the barrel through which the barrel may be charged after retraction of the piston following an extrusion operation and a port closure device is provided to close the port after extrusion and evacuate air from the barrel prior to advancing the piston past the port to minimize the air contained in the barrel prior to the extrusion operation.

Abstract: A vent-type plastication molding machine has a material supply rate control system. The reciprocal sliding motion speed of the screw in an axial direction of the heating cylinder is detected by a detector comprising a rack fixed to the reciprocally sliding portion of the machine, a pinion engaging with said rack and rotatably mounted on the stationary portion of the machine, and an electric generator connected with said pinion.

Abstract: In the case of an apparatus for dewatering and plastifying water-wet mixts of materials for manufacturing explosives, as for example mixtures for producing propellent charges, using a screw extruder with one or more screws having kneading and conveying elements and a housing, possibly made up of axial sections, with a filling port for the said mixture as wetted with water, certain steps are taken for stopping the formation of slurries at the back end or part of the screw extruder, that is to say at the filling port there is an outwardly widening drain port with a drain duct joined thereto in which there is a conveyor for clearing the expressed water and the solids therein and moving them to the back end of the screw extruder.

Abstract: An extruder including a devolatilizing section having helical channels formed in the barrel and having a cylindrical rotor closing the inner sides of the channels. Material is fed onto the rotor surface which rotates and forms the material into one or more rolling banks engaging only the upstream flank of the channels and the rotor surface. Helical vent slots pass through the barrel into each channel at the downstream flanks not occupied by the rolling bank.

Abstract: A two-stage, screw-fed vertical mechanical separator for separating a low viscosity material from a high viscosity material, wherein the bulk of the low viscosity material is removed in the first stage and the high viscosity material is heated as a result of mechanical working through a restriction into a second stage and subjected to a vacuum to flash off residual low viscosity material.

Abstract: A continuous process for carrying out the process for preparing substantially dust-free thermoset plastic particles from soft plastic mixtures of reactive thermoset plastic-forming materials and volatile components. These soft mixtures which quickly harden after drying are extruded under low pressure and are granulated by cutting while soft. To eliminate excessive amounts of dust the invention uses a premixer and a worm conveyor in a special housing and the conveyor flights are at a low angle of inclination to the horizontal to extrude the soft mixture at low pressure. The soft material at the outlet of the special material is pushed out of the nozzle under a worm rotation which is less than 25 r.p.m. and a pressure is of the order of one pound after which the material is conveyed pneumatically to a cooling station to harden and after cooling is cut into uniform size particles by knives without the formation of dust.

Abstract: A device for monitoring the filling level of the degassing space in an extruder used for processing thermoplastic materials comprises a level detection orifice located in the degassing dome or jacket of the extruder which opening is connected to a conduit. The conduit leads through a regulator device to a gas source. Connected to the conduit, between the regulator device and the orifice, is a pressure sensor such as a pressure difference switch. If the level of molten material in the dome rises above a preselected level, it blocks the opening and produces a back-pressure in the conduit. The switch is automatically actuated by this back-pressure and produces a signal. Appropriate action can then be taken to prevent the further rise of the molten material in the dome and to prevent blockage of the degassing device.

Abstract: An apparatus for separating entrained matter from a flowing fluid carrying the entrained matter includes a passage diverging at an angle of from 3 to about 20 degrees in the direction of flow of the fluid and at least one helical flight having the same twist direction throughout located with the passage and tapered to conform thereto. A straight cylindrical pipe is attached to the outlet end of the passage; the pipe contains a straight baffle interlocking to aboout 90 degrees with the helical flight. Opposed edges of the flight may be spaced from or in contact with the wall of the diverging passage.

Abstract: An apparatus and method for extracting water from rubber is provided. The rubber is screw conveyed in a twin screw extruder and alternately compressed between the forward side of the screw conveying threads, the inner extruder chamber wall and the wedge-shaped screw shaft. Water is squeezed out of the compressed rubber particles and drained off. The extruder chamber wall preferably has longitudinal grooves to impede the revolving movement of the rubber particles and to further squeeze the water from the rubber particles.

Abstract: Poly(ethylene terephthalate) resin and blends of poly(ethylene terephthalate) resin with other polymers are extruded while being coupled with an organic diisocyanate under conditions where carbon dioxide gas is vented smoothly, as it is formed. The extruder has a number of zones designed to perform specific functions. The temperature in the kneading zone and in the venting zone must be maintained at about 280.degree.-320.degree. C. to bring about rapid reaction and to permit efficient gas evolution and removal without thermally degrading the polymeric material. The extruded article is free of trapped gas bubbles and other imperfections. This process is particularly suitable for making PET billets, which then are stretched to form strapping useful in packaging applications.

Abstract: This relates to the increasing of the intrinsic viscosity of resins, particularly PET, by effecting a solid state polymerization of the resin. More particularly, the solid stating is effected in conjunction with an injection or extrusion unit wherein after having the IV of the resin increased, the heated resin may be fed dry into an injection unit thereby utilizing the heat of the heated resin to reduce heating cost. The solid state polymerization is effected by heating the resin in the presence of either a vacuum or an inert gas such as nitrogen.

Abstract: In a melting and conveying device for a plastic injection molding machine, having a melting cylinder with a cylindrical bore therein and a worm member in said cylindrical bore, a degasser, comprising, a vent pin extending into the melting cylinder in a degassing zone of the cylinder bore. The vent pin defines a widened charging pocket which communicates with the cylindrical bore and has a vent opening therethrough communicating the pocket to the atmosphere. A pair of heating elements extend into suitably provided openings in the vent pin to selectively heat the vent opening and pocket independently of any heating elements of the plastic injection molding machine to prevent clogging of the pocket and vent opening by solidified plastic material.

Abstract: In venting means for a screw extruder, particularly for thermo-plastics material, which venting means comprises a substantially vertical venting shaft communicating with the bore of a cylinder of the extruder and coupled to a low pressure source by a pipe, a pivotable flap which is moved from its normal position shown, when acted upon by plastics melt being extruded and rising in the shaft due to malfunction of the extruder, to cover the end of the pipe and prevent the melt passing into the pipe.

Abstract: Method of removing radiant, pulverulent synthetic wastes which are mixed dry with a thermoplastic mass in a kneader and then delivered from a discharge opening of the kneader into a container capable of providing a final storage therefor, while gases and/or vapors are withdrawn from degassing domes of the kneader, which includes delivering fluidic dried wastes by mechanical movement through a metering tube into a degassing dome in the kneader disposed next to the discharge opening, and admitting scavenging gas into the metering tube at least temporarily in direction toward the kneader; and device for carrying out the foregoing method.

Abstract: A screw extruder for processing thermoplastic materials wherein a vacuum is applied to the feed opening for the material and/or to a filling section of the cylinder for the purpose of reverse degasification, said extruder having a simultaneously rotating pressure piece between a screw and a back pressure bearing and having a stationary end piece disposed on the screw side in front of the rotating pressure piece and sealing means comprising at least two axially spaced radial sealing rings and a vacuum source to apply vacuum to an annular interspace formed between the sealing rings.

Abstract: This invention provides process and apparatus for the injection molding of epoxy resin molding compositions. The constituent materials of the epoxy resin feed mixture are separated into at least two groups in at least two separate chambers. Each of the chambers is subjected to a vacuum of from about 50 to 100 Torr in order to degassify the feed material and thereby avoid the formation of voids in the final molded product. The degassified molding materials are then fed under pressure to a mixing tube which may be heated. The mixing tube is connected by means of a valve having a discharge orifice alignable with the entry passage of a mold. The mixing tube, valve and orifice are movable toward the mold so that the orifice engages the mold and is maintained in engagement therewith at a greater pressure than the pressure exerted on the molding composition fed to the mixing tube and mold.

Abstract: Apparatus for introducing solid fuels into a pressure gasification reactor comprising at least one conveyor worm turnable in a housing for conveying finely divided fuel, optionally mixed with a binder, and compacting the fuel into a gas-tight plug which is discharged through a discharge opening leading to the pressure gasification reactor. The discharge opening is provided with a closure member and the housing has an outlet opening also provided with a closure member near the discharge opening. The outlet opening is open to the ambient atmosphere. The closure members of the discharge opening and the outlet opening are alternatively actuatable such that when one is open the other is closed.

Abstract: A method and device for filling containers with evaporated radioactive waste concentrates that are mixed with bitumen and from which the water has been expelled by creation of temperatures above the boiling point of water, in which the temperature of the waste mixture is substantially reduced below the water expelling temperature immediately before loading the mixture into the containers.

Abstract: An exhaust gas treating device for injection molding machines, in which a vent port of a vented injection machine is connected to a vacuum and an exhaust gas treating mechanism for treating the gas discharged from the vent port characterized in that a mist separator, the vacuum pump, an air-water separator and a deodorizing unit are disposed in the above-mentioned order from the vent port side and in communication with the vent port.

Abstract: Thermoplastic granules mixed with a blowing agent are processed in a barrel unit which encloses a rotating screw which mixes, works and plasticizes the mixture so that at the leading end of the barrel it is in a molten condition suitable for extrusion or injection molding. The screw has two compression stages with an intermediate decompression stage therebetween. At a location corresponding to the decompression stage of the screw the barrel has a vent therein which permits the escape of moisture vapors and other unwanted volatiles in the mixture. At the vent zone the forward faces of the screw flights are undercut to minimize the discharge of mixture through the vent.

Abstract: A waste gas discharging device for use in an injection molding machine including a vacuum pump connected by way of a waste gas discharging unit to a vent hole in an injection molding machine, a branch path leading to a blower and connected between the vent hole and the waste gas discharging unit, the branch path being open and closed by a firstchange-over valve, and a second change-over valve disposed between the vacuum pump and the waste gas discharging unit, whereby waste gas from the waste gas discharging unit is discharged to atmosphere, without passing through the vacuum pump.

Abstract: An improved method for forming thermoplastic articles from high nitrile polymers by injection molding which method comprises initially charging the high nitrile polymer to a vacuum hopper system wherein a vacuum is applied and from which it is fed to a reciprocating screw injection molding machine for formation of said articles.

Abstract: A multi-stage extruder apparatus comprising at least two extruder units operatively joined together in series for the progressive sequential working of plastic molding material moving continuously therethrough. The apparatus comprises an improved extrusion screw for a succeeding extruder unit of the multi-stage apparatus which prevents adverse effects attributable to an imbalance of the rate or volume of molding material moving continuously through the multi-stage apparatus.