Plastics extruders

CHODOS CHODOV s.r.o. is a historical producer of extruders, designed for processing of thermoplast processing by extrusion method in endless lengths in form of bands, hoses, bars, profiles etc. They may process LDPE, LLDPE, HDPE, PP, PS, PVC. The machines may be included in a number of lines including the re-granulation ones.

The extruder is an equipment being continuously supplied from the feeding hopper with solid thermoplast in form of pellets, powder, possibly crushed material. The thermoplast is removed at the filling opening by a rotating screw, which is located in the working cylinder, and transferred to the head located at the output from the extruder, giving the extruded thermoplast the required shape. When passing through the heated chamber, the melt flow is going through several segments of the screw. The screw makes a rotary movement, resulting in feed of thermoplast in the working cylinder and at the same time under cooperation of heat and pressure, it comes to a gradual change in liquid phase.

Basic series of extruders CHODOS

Type	031 102	031 107	031 103	031 104	031 106	031 105	031 108	031 109
Screw diameter [mm]	20	35	45	63	63	90	90	120
Screw length [L/D]	20	25	30	26	30	26	30	26

EXTRUDER PLEX 90 TYPE 031 105 M021

The first one from the new series of extruders is extruder PLEX 90, which was produced in 2016. We offer all extruders with or without evacuation.

Machine equipment – periphery based on customer´s requirements:

• pellet suction device
• spiral conveyor
• dosing / dyeing unit
• screw conveyor for even feeding of working cylinder
• extruding heads upon customer´s wish
• string head for STRING RE-GRANULATION LINE
• PELLETIZER – STRING CUTTER
• cooling troughs

MACHINE DESCRIPTION / PURPOSE

• The extruder is designed for processing of polyolephins and heat-shaped plastics by extrusion method.
• The screw makes a rotary movement, resulting in feed of thermoplast in the working cylinder and at the same time under cooperation of heat and pressure, it comes to a gradual change in liquid phase.
• The first section of the working cylinder (section under feeding hopper) is adjusted for the possibility of water cooling. The cooling intensity may be adjusted by a valve, which may be used as a closing valve after a longer shutdown of the machine.
• The output part of the working cylinder is ended with a collar to attach the extruding head and is equipped with a pressure safety lock.
• The working cylinder is tempered by totally five tempering zones, enabling three-position temperature regulation.
• The working cylinder incl. gearbox and the main motor are positioned on the frame.
• The gearbox is a two-level type with spur gearing. The gearbox lubrication is done by oil spray by toothed wheels.
• The screw, free of thermoplastic material, may be pushed out or pulled out of the working cylinder.

TERMINOLOGY OF THE INDIVIDUAL MACHINE PARTS 

• The extruder is an equipment that is continuously fed by solid thermoplast, possibly crashed material from the feeding hopper. The thermoplast is removed at the filling opening by a rotating screw, which is located in the working cylinder, and transferred to the head located at the output from the extruder, giving the extruded thermoplast the required shape and cleaning the material.
• The working cylinder consists of a hollow cylinder, equipped with flanges on both ends. In order to temper the thermoplast to the required processing temperature, the working cylinder is equipped with tempering blocks.
• Tempering block – a compact unit consisting of own ceramic resistance heating bodies and a terminal box.
• Control circuit – ensures collection, processing and transfer of information necessary for machine operation.
• Power circuit – ensures electric power of machine operation.
• Main motor – is located in front of gearbox and by being connected via a coupling, it ensures a rotary movement of the screw.
• Screw – an equipment located in the working cylinder; it ensures the removal of crushed material from the feeding hopper of the extruder and in consequence of temperature and pressure, it ensures its gradual change into melt. By its structure, it enables the release of steam and gases contained in the melt. It has a homogenization function. The screw is ended by a cone point.
• The safety cup has a safety function. It prevents the processing pressure from exceeding the unacceptable level in the cylinder.
• Melt pressure sensor – an equipment directly reading the melt pressure in front of screw peak – safety function – it blocks the extruder in case the processing pressure exceeds the set value. The meld pressure sensor may be assembled into the safety cup opening. We don´t supply the sensor as a standard.
• Feeding hopper – serves as a material storage tank.  It is equipped with a sight glass. There is a dye doser attached to the flange, connecting the feeding hopper and the working cylinder. The doser is located above the gearbox.

MACHINE PARAMETERS

            - screw diameter                                                     90 mm

            - screw length / diameter                                        26 L/D

            - main motor performance                                      51 kW

            - max. speed of screw                                            95/min

            - max. pressure on screw peak                              50 MPa

            - heating element input: of working cylinder           4 x 6000 W + 1 x 5000 W

            - heating element input on collar                            2 x 320 W

            - heating element input on head                             4 x 700 W + 2 x 450 W + 1 x 350 W

            - installed input of extruder                                     131 kVA 

     - number of tempering zones:

                        - working cylinder                                        5

                        - head                                                          4+2+1 /max.17,6A/

            - working cylinder and screw                                  active surface nitrided

            - max. operating temperature                                  300° C

            - feeding hopper volume                                         130 dm³

            - central height of screw from floor                         1000 mm

            - machine height with feeding hopper                     2000 mm

            - machine length without head                                3290 mm

            - machine width                                                       600 mm

            - machine weight (without equipment)                    approx. 2850 kg

            - amount of processed material                               max. 145 kg/h

            - gearbox assembly                                                 covering IP 54

                        height                                                           1850 mm

                        width                                                            1210 mm

                        depth                                                            500 mm

                        weight                                                           430 kg

MACHINE DESCRIPTION / PURPOSE

• The pelletizer is designed for granulation of strings from polyolephins and heat-shaped plastics produced by extrusion method.
• The pelletizer drive is secured by a motor with gearbox and a frequency convertor.
• The frame consists of a welded structure with attached feet equipped with silent blocks.
• The internal part of the frame serves to positioning of drive on an independent frame with the possibility to tighten V-belts.
• In the upper part of the frame, there is an auxiliary frame of rotor is attached.
• The height of cutting knife may be adjusted. For multiple usage, the knife may be rotated, depending on its wear.
• The construction of knife attachment enables to take up the clearance between the cutter and knife.
• The pressure may be adjusted by positioning of weight on the frame arm of pressure roller.
• The pellet discharging hopper is equipped with an opening for easy cleaning.
• The cutter drive shaft as well as the cutter may be pulled out from one side after disassembling some parts
• The covers ensure safety during the pelletizer operation.
• The pelletizer is designed for work on a production line. It must not work independently

 

• DRIVE

• FRONT GEAR MOTOR RX87 DRN160M4/TF/V
• output torque 220 Nm (there is a slight reduction in maximum speed)
• output revolutions ranging from 90 to 1750 rev/min
• motor power 11 kW
• weight 160 kg
• easy handling thanks to a small weight and small dimensions

 

• CUTTER

• documentation of CHODOS draw. No. DA007ML
• material 19436; X210Cr12
• surface of teeth hardened

• FRAME

• welded construction
• attached feet are equipped with silent blocks
• the internal part of the frame serves to positioning of drive on an independent frame with the possibility to tighten V-belts
• the cutter frame attached from upwards
• adjustable height of knife, possibility to rotate with the knife for multiple usage
• clearance taken up between cutter and knife
• pressure may be adjusted by positioning of weight on the frame arm of pressure roller
• the pellet discharging hopper is equipped with an opening for easy cleaning
• the covers ensure safety during the pelletizer operation
• the cutter drive shaft as well as the cutter may be pulled out from one side after disassembling some parts

 

• WIRING

• wiring box
• FREQUENCY CONVERTOR MOVITRAC MCLTPB0185-5A3-4-10
• speed POTENCIOMETER EP 101 10K OHM
• safety relays, emergency switch, signaling and control push buttons
• main circuit breaker, fuses, terminals

 BASIC PARAMETERS OF PELLETIZER:

• height 1544 mm
• width (incl. gearbox and drive)            1497 mm
• length (without wall connector) 1459 mm
• axis height of string inlet hole            1237 mm
• machine weight 670 kg
• nominal drive performance 11 kW
• installed capacity 19 kVA
• string drawing speed 5,5-105 m/min
• amount of processed material            according to performance of extruder