Lesson 1Haul-off and downstream: belt pullers, caterpillar haul-off, speed synchronisation with extruderReviews haul-off and downstream pulling equipment, including belt and caterpillar units. Explains traction control, nip pressure, and speed synchronisation with the extruder to maintain product dimensions and surface quality.
Belt pullers vs caterpillar haul-offSpeed synchronization with extruderNip pressure and slip preventionEffect on wall thickness and ovalityIntegration with downstream cuttersLesson 2Cooling and sizing equipment: water cooling baths, spray rings, cooling tanks, calibrators, vacuum sizing systemsExamines cooling and sizing equipment used after the die, such as water baths, spray cooling, and vacuum calibrators. Discusses heat removal rates, dimensional control, internal stresses, and the impact of cooling profiles on warpage.
Water baths and spray ring designCooling tanks and residence timeCalibrators for profiles and sheetsVacuum sizing for pipes and profilesCooling rate, stress, and warpageLesson 3Screw geometry and selection: screw diameter ranges, L/D ratio, flights, compression and metering zonesDetails screw geometry elements and their influence on melting, mixing, and pressure generation. Covers diameter, L/D ratio, flight design, compression and metering zones, and guidelines for selecting screws for different polymers and outputs.
Screw diameter and L/D ratio effectsFeed, transition, and metering zonesFlight depth, pitch, and channel volumeBarrier and mixing section optionsScrew selection for materials and outputLesson 4Instrumentation and gauges: melt pressure transducers, die pressure, barrel temperature sensors, flow meters, infrared profile measurementCovers key extrusion instrumentation, including melt and die pressure, barrel temperature sensing, and flow measurement. Emphasises sensor placement, calibration, data interpretation, and how signals feed alarms, interlocks, and closed-loop control.
Melt and die pressure transducersBarrel temperature sensors and placementFlow meters and mass flow monitoringInfrared profile and surface temperatureCalibration, drift, and signal filteringLesson 5Hopper and material handling: dryers, feeders, gravimetric vs volumetric dosing, contamination controlFocuses on hopper design and material handling, including drying, conveying, and dosing. Compares gravimetric and volumetric systems, highlights moisture and contamination control, and reviews best practices for avoiding bridging and segregation.
Hopper design, liners, and bridgingDryers and moisture specification limitsPneumatic and mechanical conveyingGravimetric vs volumetric dosingContamination and metal detectionLesson 6Additive and colour feeding systems: side feeders, loss-in-weight feeders, masterbatch feeders, pigment dispersion basicsExplores feeding systems for additives and colourants, comparing volumetric and gravimetric designs. Addresses side feeding to twin-screws, masterbatch dosing, pigment dispersion quality, and strategies to avoid segregation and colour streaks.
Volumetric vs loss-in-weight feedersSide feeders for fillers and regrindMasterbatch feeders and color dosingPigment dispersion and streak controlRefill systems and material segregationLesson 7Types of extruders: single-screw vs twin-screw — principles, advantages, typical applicationsCompares single-screw and twin-screw extruders, explaining operating principles, melting and mixing behaviour, and how design choices influence throughput, energy use, and suitability for compounding, recycling, and profile or film extrusion.
Single-screw operating principle and meltingTwin-screw co-rotating vs counter-rotatingDistributive and dispersive mixing behaviorTypical applications and material suitabilityEnergy efficiency and throughput comparisonLesson 8Cutting and finishing: flying saws, cold cutters, trimming units for profilesDescribes cutting and finishing units for extruded products, including flying saws and cold cutters. Explains synchronisation with line speed, burr and dust control, dimensional accuracy, and trimming of profiles to meet final specifications.
Flying saws for continuous profilesCold cutters for pipes and tubesCut length control and tolerancesBurr, dust, and chip managementEnd finishing and chamfer optionsLesson 9Extruder main components: barrel zones, feed throat, screw, gearbox, heaters, thermocouples, melt pumpIdentifies the main mechanical and thermal components of an extruder. Explains barrel zones, feed throat, screw, gearbox, heaters, thermocouples, and melt pump, and how their design and maintenance affect stability and output.
Barrel zones and cooling circuitsFeed throat design and ventingGearbox, motor, and torque limitsHeaters, thermocouples, and controlMelt pump function and pressure buildLesson 10Die and calibration tooling: die types for pipes and profiles, mandrels, vacuum sizing, land length and swell controlCovers die and calibration tooling for pipes, profiles, and sheets. Discusses flow distribution, mandrels, land length, swell control, and vacuum sizing, linking tooling design to dimensional accuracy and surface finish.
Pipe, profile, and sheet die typesFlow distribution and manifoldsMandrels, pins, and spider supportsDie land length and swell controlVacuum sizing plates and sleeves
