Exhaust differential double screw extruder
Technical field
Exhaust differential double screw extruder of the present invention, be widely used in industries such as oil, chemical industry, rubber, plastics, food, pharmacy, explosive and propellants, this extruder has good mixing, plasticizing, conveying and devolatilization ability, is applicable to mixing, granulation, reaction processing and the extrusion molding of multiple pellet, powder even piece material such as plastics, rubber, food and explosive.
Background technology
In industry such as oil, chemical industry, rubber, plastics, pharmacy, food, explosive and propellant, often relate to the high viscosity fluid mix, mixing effects such as shearing and plasticizing, extruder and kneader are the important equipments of realizing these effects.Double screw extruder aspect melting effect and output can be significantly better than single screw rod.For deviating from moisture and other volatile components in pellet, powder even the piece material, exhaust outlet often is set realizes devolatilization, become the exhaust double screw extruder, but melting effect is limited.
A kind of differential twin-screw kneader is provided among the patent CN201079735Y, had both had traditional kneader device to mixing, the shearing of high viscosity fluid and plastify mixing effect, had the characteristics that counter rotation twin screw extruder is extruded continuously again.In the differential twin-screw kneader course of work, two screw rods are meshing with each other.Exist the region of engagement between two screw rods,, have speed difference between spiral shell rib and screw channel, obviously strengthened mixed effect at the place, region of engagement.But the screw rod in this patent helicitic texture vertically is identical, can not adapt to the needed different helicitic textures of material different processing stages; This patent regulation male rotor number of starts is 1, and form is too single; Exhaust section is not set, and the devolatilization function is poor; And this patent is a kind of continuous kneader, can not well be applicable to the extrusion molding, granulation, mixing etc. of material.
If with the feature set of differential twin-screw kneader and exhaust double screw extruder, it is then with the obvious advantage promptly to form exhaust differential double screw extruder, has more power, thereby obviously improves exhaust, plasticate and energy-saving effect.The traditional relatively kneader of this extruder is easy and simple to handle, has good development prospect.
Summary of the invention
Exhaust differential double screw extruder of the present invention, mainly form by feeding device, machine barrel, screw rod, head, heater, exhaust apparatus, motor, transmission device, the screw rod that two engagements are arranged in inner chamber " ∞ " the type machine barrel, one is male rotor, one is female rotor, general spiral shell rib head number is many is called female rotor, and spiral shell rib head number is few is called male rotor.At least have a screw-threaded engagement district during screw combinations, the female rotor spiral shell rib head number in this district is the integral multiple of male rotor, and the rotary speed of negative and positive rotor and spiral shell rib head number are inverse ratio, can realize the differential rotation.In the screw-threaded engagement district of differential rotation, rotor section molded lines is connected in sequence by the plurality of sections curve, and negative and positive rotor end-face molded lines is corresponding mutually, and the conjugation engagement forms good engagement during differential motion, guarantee not interfere.
A female rotor can be placed on diverse location as required in two screw rods, and two screw rods can be to be arranged above and below, arrange about also can being, and can also be that the inclination mode is arranged.
In the screw-threaded engagement district of differential rotation, adjacent male helical rotors pair can be conjugation in theory, and positive conveyance ability and pressure capability are very strong.At region of engagement place, because of the very big speed difference of the different formation of screw speed, possess like this and shear and multiple effect such as stretching between the screw channel of the spiral shell rib of female rotor and screw channel and corresponding male rotor and the spiral shell rib, therefore obviously enhancing mixing and plasticizing effect.And the negative and positive rotor is meshing with each other in the process, peels off the material that is attached on the screw rod mutually, has the automatically cleaning ability.
In order better to adapt to the processing request of material, on the different sections of feeding section, melt zone, exhaust section and the metering section of screw rod, can be set to different lead and end face molded lines even change thread segment or other forms of screw rod spiral shell rib head number.The exhaust section machine barrel of extruder is provided with exhaust outlet, and the exhaust outlet device of air that runs in increases the devolatilization that exhaust outlet helps moisture and other gases, improves quality of item.Guarantee when two screw rods are installed to have at least outside the screw-threaded engagement district of a differential rotation, different sections can be engagement also can be out of mesh so that realize strengthening mixing, exhaust effect or other functions.For example, for the mixing ability of further enhancing equipment and realize stable extruding, can increase screw pin section or toothed disc etc., but not interfere must guarantee the negative and positive rotor motion time at certain section.
Description of drawings
Fig. 1 is the structural representation of exhaust differential double screw extruder
The 1-head, 2-machine barrel, 3-heating-cooling device, 4-exhaust outlet, 5-screw rod, 6-feeding device, 7-mount pad, 8-shaft coupling, 9-reduction box, 10-motor, 11-frame.
Fig. 2 is the mesh schematic representation of differential type twin-screw
Fig. 3 is for male rotor spiral shell rib head number is 1, female rotor spiral shell rib head number is 4 o'clock mesh schematic representation
Fig. 4 is 2 for male rotor spiral shell rib head number, and female rotor spiral shell rib head number is 3 o'clock a mesh schematic representation
Screw rod sectional drawing when Fig. 5 adopts screw pin for the screw mixing section with pin installing hole
Front view when Fig. 6 adopts the mesh plate element for the screw mixing section
Side view when Fig. 7 adopts the mesh plate element for the screw mixing section
Specific embodiments
Case study on implementation one
Design exhaust differential double screw extruder, screw engages such as Fig. 2 according to Fig. 1.Two screw rods 5 adopt spread patterns such as Fig. 3 in the extruder.Wherein, in the screw-threaded engagement district, male rotor spiral shell rib head number is 1, and female rotor spiral shell rib head number is 4.Pot motor is given the negative and positive rotor by reduction box 9, shaft coupling 8 with torque distribution, and the ratio of its speed is that 1/4, two male rotor rotates in the same way, and female rotor and male rotor are incorgruous rotation.Screw rod 5 assemblings are placed in the barrel 2 that is fixed in mount pad 7, have exhaust outlet 4 on the barrel 2, regulate temperature by outer dress heating-cooling device 3, and barrel 2, reduction box 9 and motor are directly installed on the frame 11.
Add material to be processed from charge door 6, material becomes molten condition by pellet or powder after Solid Conveying and Melting, compression fusion.During through exhaust outlet 4, moisture and volatilization gas in the material are discharged machine barrel via exhaust apparatus.Near head 1 mixing section is set on the screw rod, adopts the screw form with holes of settling pin among Fig. 5.Pin plays and cuts apart materials flow on the screw rod, increases the interface, by repeatedly shunting, converge, and reorientation and realize distributing and mix.Material is extruded by head 1 after passing through mixing and exhaust.
Case study on implementation two
Be similar to case study on implementation one and form exhaust differential double screw extruder.It is 2 that difference is in male rotor spiral shell rib head number, and female rotor spiral shell rib head number is 3 (Fig. 4 is seen in the differential engagement of screw rod), distributes through the speed of reduction box, and the ratio of negative and positive spinner velocity is 2/3; Screw rod adopts Fig. 6 and mesh plate form shown in Figure 7 at the mixing section near head 1, helps distributing mixing, and produces lower processing temperature.