1. Screw: 38CrMoAlA high quality nitriding steel, quenched and nitrogen treatment; The spiral surface hardness >HRC62, hard layer depth 0.55-0.7mm; Helical structure in the extrusion and feeding phase with Isometric deep structure; In the plastication stage with main/subsidiary threads structure; This spiral form has the advantage of high strength, high feeding capacity, excellent plastication effect, low temperature of extruding product, shear mixing sufficiently, stable extrusion pressure, good adaptability for all kinds of rubber materials. There is cavity in the middle of screw for heating and cooling system. Make 1 hour water pressure test of 10kg/cm2 for screw cavity.
2. Barrel: Outer barrel is made of high quality carbon steel, An axial channel is drilled in a circle for heating and cooling; Inner bushing adopts 38CrMoAlA high quality nitriding steel, quenched and nitrogen treatment, surface hardness HRC66-70, hard layer depth 0.55-0.7mm; Bushing is installed in the feeding barrel and it is changeable; Bushing outer diameter of the ring is formed with an annular groove for heating and cooling.
3. Feeding device: Consist of feed rolls, roll covers, bearing blocks, gear pairs, bearings, scraping knives and so on. Special advanced design structure can effectively prevent the material into the feed roller support bearings, to ensure the proper running of the feeding apparatus and no leakage of materials. Feed roller surface and anti-rubber groove are quenching treatment, with surface hardness HRC62-70 and hardness layer depth 0.5-1mm. Gear pairs have a separate lubrication system and adopt 20CrMoTi with nitriding treatment & hard layer thickness 1.5mm. Feeding roll gears are high strength and wear-resistance. Feeding device is mounted at the side of the machine body.
4. Feeding zone barrel: Involves body, front bushing and rear bushing. The bushing is made of 38CrMoAlA high quality nitriding steel, quenched and nitrogen treatment, surface hardness HRC66-70, hard layer depth 0.55-0.7mm. Body material adopts ZG270-500, forged with cavity for heating and cooling system.
5. Reducer: Equipped with extruding machine special use level 2 reducer, hardened gear, low noise <85db. Gear pairs are immersed in the lubricating oil to ensure adequate lubrication of the gear pair. Gear shafts and gears adopt two different high-quality high-strength low-carbon alloy steel, gear tooth surface treated by carburizing and grinding, gear engagement precision Class 6. Reducer adopts separator forced lubrication system with oil scaling indicator and oil exhausting exit. It has air exhaust exit on the top of reducer.
6. Driving motor: DC motor & converter, the steady-state precision less than 0.1%, with constant torque characteristics, equipped with motor speed measurement device and thermal resistor.
7. Temperature controlling system adopts direct cooling automatically to control the temperature of extrusion head, barrel and screw separately, totaling 4 units. Extruder is equipped with 4 units temperature controller (heating power: 12kw/unit). It is electric heating and water cooling. Circulating device uses WILO to have stable process and optimize the extruding performance, equipped with temperature monitoring and automatic adjustment system. The temperature accuracy is ±2ºC and temperature can be set automatically.
a. Every unit is controlled separately.
b. Soften water should be used with inputting water pressure 2-3KG/CM2
c. Electric pipe heating.
d. Adopts RKC temperature controller and intelligent PID adjuster.
e. Temperature control accuracy±2ºC, Temp.
f. Automatic protection function includes automatic water replenishment, hot water circulation pump can not start and heater will not heat at dry state or no water state, over-temperature alarm and automatic power-off, auto-exhaustion and so on.
8. Extrusion head: Consist of upper head body, bottom head body, die plate, damping plate, end cover, adjusting bolt and so on. The extrusion head body: #45 forging, along the axial processing of the channel, for the head body of heating and cooling, special flow channel design can ensure uniform pressure inside the extrusion head, the same speed and easy to adjust. The flow passage plate adopts the embedded structure, and can be changed according to the specification of the product. Extrusion head body are fastened by bolt.
9. Electric control system:
a. DC speed adjuster adopts Eurotherm brand, with digital display and stable performance.
b. Main breaker and electric parts use CHINT, Chinese famous brand.
c. Have the function of over-current, overload, phase loss, under-voltage, zero speed starting protection.
d. Main controlling cabinet has cooling fan.
e. Panel display function: Main motor current, voltage; Screw speed; Power, voltage.
f. Operation function: Main motor start, stop and its instruction; Motor speed adjuster; Trouble alarming; Emergency stop.