Abstract: A mixing device is placed in a stream of material flowing in a longitudinal direction for mixing constituents in the stream, the mixing device including a plurality of mixing elements spaced apart from one another and projecting transversely into the oncoming stream of material. The mixing elements are spaced laterally from one another and each mixing element has a cup-shaped upstream face for confronting the oncoming stream of material while allowing the stream of material to flow in the longitudinal direction, between the laterally spaced apart mixing elements, to effect enhanced mixing with lower shear.

Abstract: An axially elongated extruder screw includes a screw body having an axially extending extruding portion defined by a feed section at an inlet end of the screw, a metering section at an outlet end of the screw and a barrier section between the feed and metering sections. A first helical primary flight extends continuously about and is coaxial with the screw body substantially along the entire length of the extruder screw. A second helical primary flight extends continuously at least part-way along the feed section to the outlet end of the extruder screw. The barrier section of the extruder screw defines first and second barrier flights positioned between the primary flights and cooperating therewith to form first and second melt and solids channels that extend along the barrier section of the extruder screw.

Abstract: An apparatus and process for chopping and mixing a polymeric material having an elongated hollow barrel element with a material inlet end and a material outlet end and housing a rotatable extruder screw. The rotatable extruder screw includes at least one flightless screw section and at least one stationary tube element made from a bearing material and forming a plurality of serrations at at least one end, the stationary tube element being disposed around the flightless screw section within the elongated hollow barrel element and fixed against rotation with respect to the elongated hollow barrel element. The flightless screw section forms at least one material melt recess in a region corresponding to the serrations of the stationary tube element. Extruded products requiring, and characterized by, low shear, uniform dispersive mixing are made in one process step in a single screw extruder employing this invention.

Abstract: A mixer for plasticable resins has a fixedly positioned heated barrel with a power driven screw mounted axially in the barrel bore, a driven rotor is axially aligned with and extending in a downstream direction from the downstream end of power driven screw. A series of elongated rotor flow transfer cavities are in the outer surface of the rotor. The rotor flow transfer cavities extending inwardly and are arranged in a plurality of axially aligned rows and a plurality of annular rows concentric to the axis of the rotor. A floating sleeve is coaxially positioned over the power driven rotor and interposed between the rotor and the barrel so as to be capable of independent rotation relative to both the power driven rotor and the barrel.

Abstract: An apparatus for shearing and straining polymeric process material, such a scrap tires includes a rotor and barrel. Large material pieces are feed into a hopper and the material is warmed, pressurized and transported to a rotor--barrel transfer section to initially chop the material to reduce its size. The material then passes to a rotor barrier or refining section where the material must pass over wide top barriers that extend across extrusion grooves. The barriers included multiple ridges and the barrier to bore clearance is progressively reduced as the material passes downstream. Ramp like grooves, where rejected material can be worked further, precede the barrier ridges. A rotor to barrel transfer section, having a conical barrel that can be longitudinally shifted, follows the wide top barriers, so the size to the discharged material can be regulated.

Abstract: An extruder for extruding an associated material includes an extruder housing that has a feed section, a center section that includes a throttle section, and an outlet section with an extruder screw disposed in the extruder housing. The extruder also includes a throttle at the throttle section. The throttle has a plurality of pins that extend radially into the housing. The pins are adjusted by a cam extending around the extruder housing. The cam has an inner wall that has a plurality of cam surfaces engageable by pins. The radius of each of the cam surfaces gradually decreases from a maximum radius to a minimum radius distance. The pins have springs that urge the pins radially outward to contact the inner wall of the cam. The cam is rotated by a piston and cylinder assembly. The extruder further includes sensors for temperature, gauge, weight, and other properties of the material.

Abstract: A mixer for delaminating, deagglomerating, mixing, and extruding a mixture of powder and liquid, which contains a mixing chamber, a variable speed rotating shaft disposed within the chamber, a multiplicity of stators extending from the interior wall of the chamber towards the shaft, and a multiplicity of differently configured auger blades connected to the shaft. The device contains a first, second, and third set of auger blades, each of which is connected to the shaft. The first set of augur blades has a pitch which is at least twice as great as the pitch of each of the second and third set of augur blades, and it also has a smaller face area.

Abstract: The present invention comprises an extrusion arrangement for the controlled compounding and mixing of a plurality of time, pressure and condition sensitive substances in a single screw plastic extrusion machine, having a main support shaft connected to the downstream end of a single screw plastic extrusion machine, the support shaft enclosed within a barrel shaped housing, at least one stator and one rotor being disposed about the support shaft within the barrel shaped housing, and at least one satellite extrusion feeder arranged to supply an additive to the barrel shaped enclosure through an introduction port, the introduction port arranged at a location radially adjacent a rotor on its support shaft.

Abstract: A kneader with a vent function, including a kneading extruder, which permits the continuous viscous flow of material to be kneaded even at a high speed rotation to prevent the generation of cuttings and exhibiting sufficient venting capability. The kneader includes a barrel having kneading chambers defined therein, a rotor rotatably inserted into the kneading chambers, and having a feed portion on an outer peripheral surface thereof. A vent port is in communication with the kneading chamber of the barrel at a position around the feed portion. The feed portion in a vent zone includes a screw tip having a material feed surface with an outwardly curved surface in section.

Abstract: An extruder apparatus for use in straining refining, separating and extruding thermo-plastic and rubber like process material includes a rotor positioned in barrel with a barrier section located between two barrel sections. The portion of the rotor in the barrier section has a smooth surface and the smooth surface and the barrier section are conical. The barrier section includes receiving and sending grooves separated by barriers. All material passing through the barrier section passes between the barriers and the smooth rotor section. Longitudinal movement of the smooth rotor section changes the clearance between the barriers and the rotor to restrict flow between a maximum flow and a closed position. The clearance can be adjusted so that different materials can be extruded in the same apparatus and adiabatic flow can be achieved. Discharge ports at the downstream end of the receiving grooves port rejected material to atmosphere.

Abstract: A retruder having a housing with a pair of counter-rotating worm gears axially mounted within said housing for counter-rotation to process a medium. The housing has an inlet and also an outlet through which the processed medium is discharged which is transverse to (radially of) the housing axis. An insert in the housing is selectively slidably movable along the housing axis to overlie the outlet to adjust its size.

Abstract: This invention relates to extruders of the type which employ single screws that use chaotic mixing to generate substantially better distributive mixing. Such structures of this type, generally, stretch and fold material lines repeatedly such that interfacial areas between material elements increase exponentially and heat/mass transfers are greatly enhanced.

Abstract: A screw-type extruder in which the wall of the cylinder receiving the screw has an annular recess which is disposed in a radial region of a core bead of the screw and pins extend through this recess and are diagonally inclined to the radial plane thereof close to the circumference of the bead.

Abstract: An apparatus is disclosed for processing extrudable materials in such a way as to apply a controlled and predetermined degree of shear force to the materials. Typically, an extruder apparatus includes a housing having first and second screws mounted therein for rotation on a common axis, the arrangement being such that longitudinal thrust forces exerted by the first screw are at least partially compensated by corresponding forces generated by the second screw, inlet means for introducing material to be processed into the housing and a shear generating device located between said screws, said device including a restriction through which material is forced from said housing to exit from said housing. The restriction is preferably an annular gap formed by a sleeve fixed relatively to the housing and a shaft portion which extends into the sleeve.

Abstract: A kneading apparatus includes a plurality of rotatable discs mounted on a screw shaft disposed on a hollow cylinder and a plurality of fixed doughnut members mounted on an inner wall of the hollow cylinder. The rotatable discs and fixed doughnut members are arranged alternately in an extending direction of the screw shaft. Projected portions and recessed portions extending radially and alternately arranged in a circumferential direction are formed on opposing side faces of the rotatable disc and fixed doughnut members in such a manner that the depths thereof are increased in proportion to the distance from a center of the screw shaft. Accordingly, the kneading apparatus is allowed to have a small construction and yet capable of efficiently kneading the material. In addition, material is prevented from remaining locally in the apparatus, and thereby a proper shear force is applied to the entire material.

Abstract: An extrusion apparatus or extruder for mixing and extruding of thermo-plastic and rubber like process materials has a rotor member rotatable within the bore of a barrel member. Interposed between the feed end and the discharge end, the rotor and barrel members are provided with one or more mixing stages, consisting of process material transfers, rotor to barrel, barrel to enlarged rotor, enlarged rotor to enlarged barrel, enlarged barrel to enlarged rotor, enlarged rotor to barrel and barrel to rotor. Each process material transfer has the rotor or barrel member provided with multiple grooves which communicate with co-acting receiving rotor or barrel member multiple grooves. Each revolution of the rotor transfers process material from each sending groove to all of the co-acting receiving grooves, an action which reduces the thickness of the transferred material in the ratio of one to ten.

Abstract: A screw extruder having a barrel with a longitudinal bore for receiving a rotatable screw, a transverse bore disposed in the barrel tangential to the longitudinal bore for receiving and supporting a pin wherein the pin extends partially into the longitudinal bore. The tangential arrangement of the pin substantially decreases the susceptability of the pin to bending or breaking. The pin may also be adjustably positioned in the transverse bore and further may be subject to thermal heating and cooling.

Abstract: A Transfermix cold feed extruder having a plasticizing section that includes a plurality of screw flights therein in a transfer zone that is formed over a common length of the screw and barrel of the extruder. In the transfer zone, a helical groove in the screw varies in cross section from a full area to a zero area, and a helical groove of opposite hand in the barrel correspondingly varies in cross section from a zero area to a full area. The extruder is provided with a set of flow deflectors in a cut in the screw positioned immediately upstream of the plasticizing section. By the coaction of the flow deflectors with the plurality of screw flights, an increase of throughput for difficult-to-extrude compounds, with an improvement in the quality of the extrudate, is obtained in a surprising manner.

Abstract: The invention provides an apparatus for mixing and kneading materials comprising a housing defining a mixing and kneading chamber, a jacket member enclosing the mixing and kneading chamber and a mixing and kneading member located in the interior of the mixing and kneading chamber. The mixing and kneading member is driven to a rotating and/or oscillating motion. For supporting the mixing and kneading operation, projection members are provided protruding from the jacket member into the interior of the mixing and kneading chamber. In order to simplify the design of the apparatus and, particularly, to improve the heating and cooling of the mixing and kneading chamber, at least some of the projection members are connected directly to the jacket member, or at least some of the projection members are integrally formed with the jacket member thus constituting a common jacket member/projection member unit.

Abstract: A process and an apparatus for optimal operation of a high-speed extruder in which a pin-lined barrel section and a Transfermix section, both known per se but separately used, are utilized together in an extruder. The combination of these mixing systems allows in a surprising way an increase in the material throughput of 60% to 100%, with the mixing quality remaining the same and the drive torque being halved. The static extrudate pressure can be further increased by arranging an adjustable restriction device downstream of the extruder screw, thereby permitting a further increase in the output rate.

Abstract: Screw extruder for working plastic compositions, especially polymers and rubber mixtures having a cylinder in which a motor-driven screw is disposed. The cylinder being provided with pins which are disposed in planes perpendicular to the cylinder axis and can be pushed radially through openings in the cylinder wall, and the screw being provided in the pin planes with gaps in the screw spirals. The object of the invention is to create a practically achievable and economical possibility for the shifting and depth adjustment of pins in screw extruders. A plurality of pins, lying in an axis parallel row, are fastened to a beam at the extremities projecting from the extruder cylinder.

Abstract: A pin transfer extruder is provided, wherein the pin-barrel and transfer mixing sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. Throttle pins, which are disposed in the transfer mixing section in the region of the greatest housing thread volume, permit universal use of the extruder in respect of the extruded material. The combination of both mixing systems permits the throughput of material to be increased in a surprising manner by 60% to 100%, while a constant mixing quality is maintained and the driving torque is halved. The number of the housing and screw flights remains independent of the cross-sectional area of the housing and screw threads because the number of housing and screw threads is constant.

Abstract: A pin transfer extruder is provided, wherein the pin-barrel and transfer mixing sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. Throttle pins, which are disposed in the transfer mixing section in the region of the greatest housing thread volume, permit universal use of the extruder in respect of the extruded material. The combination of both mixing systems permits the throughput of material to be increased in a surprising manner by 60% to 100%, while a constant mixing quality is maintained and the driving torque is halved.

Abstract: A resin extruder in which the degree-of-kneading of the resin can be effectively controlled. The invention can be applied to both a single-screw extruder and a twin-screw extruder. In either case, blocking walls are formed around a cylindrical portion of the screw or screws just upstream of the kneading section. A valve structure is provided in the walls to control the kneading of resin at the kneading section.

Abstract: A single-screw degassing extruder for thermoplastic plastics materials and rubber is provided, wherein the pin-barrel and transfer sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. Throttle pins, which are disposed in the transfer section in the region of the greatest housing thread volume, permit universal use of the extruder in respect of the extruded material or combinations of extruded material and stripping agent, since the mixing efficiency of the extruder and the pressure of the extruded material upstream of a degassing opening in the extruder are thereby advantageously controllable.

Abstract: A high-performance extruder is provided, wherein the pin-barrel and transfer mix mixing sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. The combination of both mixing systems permits the throughput of material to be increased in a surprising manner by 60% to 100%, while a constant mixing quality is maintained and the driving torque is halved.

Abstract: A centrifugal bowl is intermittently cleaned of concentrate by a scoop which projects into the bowl and is indexed in a direction axially of the bowl and moved radially of the bowl to enter each in turn of a plurality of annular grooves formed on the bowl surface. The fluidized material in the groove enters the scoop and is extracted from the scoop by suction.

Abstract: For the improvement of the reaction and mixing effects of extruders, expanders and similar devices, as well as for the increase of the energy yield, the so-called scraper fingers (1) employed in such devices are provided with flats or recesses (4'). In addition, the scraper fingers (1) are disposed rotatably around an angle, so that the surface facing the advanced product in the screw space (12) can be varied. The twisting is adjustable from the outside of the jacket of the apparatus. The fingers (1) have at least one center bore (6), from which there issue side bores (8) in optional directions. In addition to a flat or recess (4'), the fingers (1, 4) can also have twisting (4') within themselves.

Abstract: An extruder for the extrusion of a material composed of a mixture of substances in which an extruder screw is rotatably mounted in a feed channel of a housing for advancing the material to an outlet, of the channel whereat a screw tip is coaxially mounted on the extruder screw and is disposed with clearance in a distributor channel extending in prolongation of the feed channel to receive the material from the extruder screw and feed the material to a discharge outlet of the distributor channel. The screw tip has a discharge surface at an end thereof remote from the extruder screw, which includes a plurality of surface portions ascending generally helically in the direction of flow of the material. The surface portions can be flat or form a continuous discharge surface.

Abstract: In a copending application Ser. No. 298,065 filed Aug. 31, 1981 modular mixing apparatus has been disclosed combined with a barrel and main power driven extruder screw and the mixing apparatus is necessarily required to be at the same speed as the main power driven extruder screw and operates through a common barrel member.In the present invention improved modular mixing apparatus has been constructed and arranged to operate with independent drive means for rotation in a separate stationary sleeve member and extruded material leaving the main extruder screw and barrel is introduced into the mixing module. The mixing apparatus may, in this form, be driven at variable speeds which are independent of the speed of the main extruder screw.The improved modular mixing apparatus of this invention also includes a newly devised shearing lug module.

Abstract: A pin-barrel extrusion device having a barrel temperature control means between the outer and inner hollow cylinders of the barrel and an apparatus for adjusting the radial depth of penetration of the pins into the inner hollow cylinder is disclosed in which problems due to different rates of thermal expansion of the cylinders in the axial direction are obviated or at least minimized. This is achieved by locating the pins in guide sleeves, which sleeves are detachably mounted in a bore formed in the inner cylinder and pass through aligned bores in the outer cylinder. The outer cylinder bores have a diameter larger than that of the sleeves so that an annular gap is defined between the bores and the cylinder. This provides room for movement of the sleeve if the inner cylinder on which it is mounted expands at a different rate to that of the outer cylinder.

Abstract: This disclosure relates to an extruder including a casing which forms a cylindrical bore and a peripheral passage for a heating or cooling medium around the bore. A screw is mounted in the bore and axially fixed to the casing, but adapted to be rotated in the bore. The screw has a thread forming a spiral passage for rubber materials in the bore. A number of projections extend from the casing and into the spiral passage, and the thread is formed with notches for the projections to pass through as the screw rotates. A cylindrical sleeve is mounted within the casing and supports the projections. The casing and the sleeve are divided or split into at least two parts, and lock means is provided on the casing to lock the parts together during operation.

Abstract: A helically moving fluid body leaving an extruder screw and brought into contact with rotating shearing means, undergoes laminar displacement, is then guided through a stationary sleeve along undulating linear paths of travel of relatively short axial length, and thereafter undergoes further laminar displacement and discharges into a die.During movement of the fluid mixture along the undulating linear paths of travel subdivision and blending of substantially all of the material in the fluid body, which is not in a fluid state, takes place. Thereupon the blended mixture is advanced to a die member at a desired fluidity and temperature in response to die requirements. Heating of the barrel is significantly reduced and energy conservation of an appreciable nature is achieved.In carrying out mixing as noted above there is employed a modular mixing apparatus constructed with multiple processing means suitable for shearing, kneading, flow diverting, dispersing, blending and the like.

Abstract: A single-screw extruder for producing thermoplastic and elastomeric products includes a hollow cylindrical barrel, which is provided with radially inwardly protruding mixing elements, which are adapted to move through recesses formed in one or more helical lands of a screw, which is rotatably mounted in the barrel. To facilitate the assembly of the screw extruder and to permit repair thereof without a need to replace the entire housing, the mixing elements (9) are provided on split rings (9), which are held axially spaced apart by interposed spacing rings, or which are clamped in position in grooves formed in adjacent annular sections of the barrel.

Abstract: A pin-barrel extruder of the type used for processing rubber or thermoplastics materials, for extracting liquids from liquid-solid mixtures and for pulping wood substances includes adjustment means which permit the depth of penetration of the pins, which project into the hollow barrel of an extruder, to be adjusted in a continuous manner. To achieve this, the pins are threadly located in throughbores provided in the barrel so that their radially outer ends project externally of the barrel. On the externally projecting end of each pin, a chain wheel or sprocket is provided which is driven by a chain drive. Actuation of the drive thus alters the depth of penetration of the pins in the barrel.

Abstract: A pin-barrel extruder suitable for processing rubber and thermoplastic plastics materials having pin adjustment means is disclosed. The extruder comprises a barrel having a screw rotating therein. Pins project radially inwardly into the hollow interior of the barrel. These pins are distributed both uniformly around the periphery of the barrel and in axial alignment with one another. Axially aligned pins are made adjustable, with regard to their depth of penetration into the barrel by being connected to a bar or rail. This bar or rail is disposed radially outwardly of the barrel but extends parallel to the axis thereof. Actuating means are provided for displacing the bar or rail, and hence the pins, relative to the barrel.

Abstract: A screw extruder for mixing, homogenizing, and degassing highly viscous rubber mixtures and similarly acting thermoplastics. The extruder has mixing pins associated with the housing in the mixing and homogenizing zone, and degassing pins associated with the housing in the degassing zone. The degassing pins have passages or channels through which gases and vapors are withdrawn. The retaining or damming structure at the entrance to the degassing zone can also be formed of pins associated with the housing. The conveyed material is mechanically and thermally satisfactorily made uniform by the inventive pin arrangement without material shearing forces, and can also be effectively and favorably degassed. High flow-through rates of the material can be achieved with high product quality.

Abstract: In an extruder, for extruding thermoplastic synthetic material or rubber or for use for pressing water out of a material, a screw rotates in a cylindrical chamber and helical conveying lands provided on the screw are interrupted at positions at which pins project into the chamber thereby forming grooves to receive the pins. To sense breakage of a pin, for example caused by metal particles in the extrudate, signal-generating means are provided in a blind bore in each pin, receipt of a signal from the signal generating means causing the screw to be stopped from rotating thereby to prevent further damage.

Abstract: An extruder which serves for kneading and extruding rubber and synthetic material mixtures. The extruder is equipped with a rotatably mounted screw, and pin bodies which project into the interior of the housing. These pin bodies can be damaged, and in particular can be bent or even broken. In order to quickly determine these failures, and possibly to even determine deformed pin bodies, the latter are incorporated into an electrical monitoring circuit. The pin bodies are provided with electrical inserts which influence the monitoring circuit when deformations or breakage of the pin bodies occur, in order in this way to transmit a signal or even electrically switch off the extruder. In place of the electrical inserts, photo conductors can be used, the optical conductivity of which can be utilized for determining the aforementioned damages.

Abstract: An extruder, including a rotor and a barrel, having mixing or working zones therein in which the material being mixed or worked is transferred layer by layer from upstream grooves in the rotor to input grooves in the barrel, and from output grooves in the barrel, which grooves are interleaved with the input grooves, layer by layer back to downstream grooves in the rotor. The input and output grooves of the barrel are intercommunicated by means of corresponding channels each of which has a selectively radially movable throttling member positioned therein for varying the cross-sectional opening of the channel in which it is positioned and, thus, the amount of shearing action and work performed on the material passing through such channel.

Abstract: A helically moving fluid body leaving an extruder screw and brought into contact with rotating shearing means, undergoes laminar displacement, is then guided through a stationary sleeve along undulating linear paths of travel of relatively short axial length, and thereafter undergoes further laminar displacement and discharges into a die.During movement of the fluid mixture along the undulating linear paths of travel subdivision and blending of substantially all of the material in the fluid body, which is not in a fluid state, takes place. Thereupon the blended mixture is advanced to a die member at a desired fluidity and temperature in response to die requirements. Heating of the barrel is significantly reduced and energy conservation of an appreciable nature is achieved.In carrying out mixing as noted above there is employed a modular mixing apparatus constructed with multiple processing means suitable for shearing, kneading, flow diverting, dispersing, blending and the like.

Abstract: Apparatus for treating powdery rubber mixtures to form processed intermediate products comprises volumetric metering means; a filling extruder; a mixing and plasticizing portion located at the downstream end of the filling extruder and having a central toothed spindle, toothed planetary spindles and an internally toothed housing; and forming out means shown as an extruder cascade connected to the mixing and plasticizing portion and extruding material through a perforated plate with cutting blades. The mixing and plasticizing portion is of only short length and can effect intensive working but does so for only a short period of time on the material passing therethrough so that the material is not damaged by being over-heated.

Abstract: A continuous kneader comprising a rotary screw shaft and rotatable within a cylinder for transporting a fluid axially thereof, rotary disks mounted on the shaft and each formed on each side surface thereof with radial projections and recesses arranged alternately, and fixed disks provided on the cylinder and arranged on the opposite sides of each rotary disk coaxially therewith as opposed thereto. Each of the fixed disks is formed on each side surface thereof with radial projections and recesses arranged alternately. The boundary between and defining each projection and the recess adjacent thereto on at least one of the rotary disk and the fixed disk is inclined from the radial direction so that the material supplied from a space between the shaft and the inner surface of the cylinder to the space between the rotary disk and the fixed disk is passed over the rotary disk outer periphery toward the axis of the shaft into the space between the rotary disk and the fixed disk immediately adjacent thereto.

Abstract: A single-screw extruder and process for mixing viscous materials, for example, rubber mixtures and thermoplastic materials. The process and apparatus includes inserting a plurality of obstacles in the flow path of the material stream in the interior of the extruder cylinder. The obstacles are in the form of a number of series of studs protruding into the cylinder and accommodated by respective gaps or openings in the threads of the screw. The depth of penetration as well as the number of studs can be varied and adjusted by automatic means. The penetrating portion of the studs can be of different shapes according to the requirements for a thorough and turbulent deflection and mixing of the material stream.

Abstract: The plastics processing machine employs a mixer which has a static mixing device formed of at least one insertion member composed of guide elements in layers which form flow channels. The hydraulic diameter d.sub.h is made no more than eight millimeters (8 mm) in order to obtain a high mixing quality. The hydraulic diameter may vary along the mixer, for example by decreasing from the inlet end to the outlet end.

Abstract: A plasticizing device for an injection molding machine for plastics comprises a screw housing having a cylindrical plastic material chamber at one end having a discharge opening. A cylindrical screw is rotatably and axially displaceably mounted in the housing and has a screw head portion adjacent the discharge with an intermediate body portion of reduced diameter adjacent the head portion and a uniform diameter portion on the opposite side of the intermediate portion from the head portion. The uniform diameter portion carries a spiral screw thread which projects radially outwardly from the surface of the screw. A seal ring having an outer periphery engaged with the interior of said screw housing and having an interior diameter greater than and spaced radially outwardly from the intermediate portion of the screw defines a plasticizing material passage with the intermediate portion which connects through a passage defined between a seal washer on the screw which cooperates with the seal ring.

Abstract: An apparatus is provided for the mixing and extruding of thermo-plastic and thermo-setting materials in which a rotor member is rotatable within a barrel member. The members are provided with interacting rotor and barrel helical grooves in the mixing stage of the apparatus which includes a rotor to barrel stock transfer zone and a barrel to rotor stock transfer zone. The grooves of the rotor and barrel members, in the rotor to barrel zone, being sized, with the extrusion capacity of the helical groove in the rotor member decreasing and with the helical groove in the barrel member providing the extrusion capacity for the material. With such a construction relative rotational movement between the barrel and rotor members forces material or stock from the groove in the rotor member into the groove of the barrel member at an approximate uniform rate along the length of the rotor to barrel zone.

Abstract: An improved screw feeder such as may be used for conveying ligno-cellulosic materials such as wood chips, shavings, sawdust and the like to pulping apparatus includes a plurality of stopper bars positioned symmetrically about the inner periphery of the screw feeder throat inlet. The stopper bars are narrow, elongate wedge-shaped and extend from the greater diameter flare bore of the conical throat to the lesser diameter taper bore. The stopper bars prevent material from rotating with the screw rather than advancing longitudinally through the throat and thus decrease plugging and clogging problems so that a higher pulping capacity due to improved feed is obtained.

Abstract: A process for admixing additives to plastics and simultaneously removing volatile constituents in a horizontal devolatilizing extruder. Taken in sequence in the direction of flow, the additives are first introduced into the devolatilizing extruder from above, and the plastic melt, solution or dispersion is then introduced from below, while the bulk of the volatile constituents are withdrawn from the devolatilizing extruder at an orifice located vertically above the point at which the plastic is fed in. The process permits the removal of volatile constituents with simultaneous admixture of additives during aftertreatment of plastics, in a single step and at very high throughputs.