INJECTION MOULDING OF PLASTICS INJECTION MOULDING

Transcription

1 INJECTION MOULDING OF PLASTICS INJECTION MOULDING The Material Hopper The Barrel/Cylinder heating system The Barrel/Cylinder and Screw Adhesion Abrasion Corrosion Datamination The Screw Drive System The Stationery Platen The Mould The Moving Planten and Tie Rods The Clamping Unit To Close and open the mould To eject the parts To keep the mould closed during the injection cycle Check these item for trouble moulds General check list for new moulds Machine Mould Design General Mould Analysis Software Co-ordinate Measuring Machines Benefit to Processors Granulator Check List Metal Separators Geneal Performance Data SETTING UP MOULD AND MACHINE Moulding Set up Time Check list for Start up Processing Some Initial Consideration Number of Shots/Cycle Time Plasticizing Capacity/Rate Clamp Tonnage Mouldability Features Part Removal The Sprue Runner System Cold Slug Well Gate Location Gate Size Cores Vents Undercuts Melt Rheology Purging

2 Set Clamp Cycle Clamp Data Pressure, Feed, Speeds Timers in Sec. Temp, Cylinder, Nozzle & Nozzle Valve First Shot Mould Mounting Data Mould Placement Removal Water Data Temp Cavity Position Temp. Core Position Mics. Columns as needed Estimating Cooling time during injection moulding Setting up a Moulding shop Accessories for the injection unit Hygroscopic Plastics Operations and Controls in Injection Moulding EFFECT OF PROCESSING ON MECHANICAL PROPERTIES Molecular Orientation Residual Stresses Melt Elasticity Melt Fracture Weld Lines Accurate Dimensions Cooling Rate Weigh Feeding and Blending Feeders Weigh Blenders Controls Processes Control Method in Injection Moulding Factors that Affect Reproductive Behaviour of Injection Moulding Machne In Line Injection Compression Equipment MOULD FLOW What is Mouldflow How Mouldflow can help Part Designers, Mould Maker & Processor How mouldflow can help Mould Designer How Mouldflow can help a Processor How to improve Quality & Productivity using Mouldflow Hydraulic System Noise Suppression The main causes of noise are Some suggestions for Noise Reduction Injection Moulding Section Estimating Cooling Time How Cooling Affects the Cycle Time How Wall thickness impacts Cooling Time Cooling Channel Diameter and Placement

3 How Turbulent is Enough Energy Consumption in Injection Moulding Injection Moulding Control System Mechanical Properties Dimensional Accuracy Surface Quality Basic Methods for control are Temperature Controls Pressure Measurement Disturbing Factor that affect smooth operation are Clamping Injection Micro Process Controls in Moulding Standard Functions Monitoring Functions Control Functions Note COMPUTER CONTROLLED AUTOMATIC INJECTION MOULDING MACHINE Clamping Side Injection Side Machine Maintenance Make Sure the Oil is Clean Examine Control Cabinet Fitters Check Water Quality Pay Attention to Toggle Link Lubrication Monitor Machine levelling Beware to How you square Inspect Heater Bands Watch safeties Stop Look, Listen Mould Placement Purging Mould Removal from Press Moulding Machine Mould Steels Plastic Mould Steels requirements New Mould Materials (Alloys and Powder Metals) Two component Injection Moulding (Sandwich Moulding) Back Pressure Injection Technique MAINTENANCE OF INJECTION MOULDING MACHINE Daily Maintenance Daily Maintenance Monthly maintenance Inspection at Three month intervals Inspection at six month intervals Annual inspection Daily Maintenance Attention

4 Piping installation Controls of Hydraulic and Lubricating Oils Trouble Shooting of Hydraulic Circuit Problems and Possible causes Noisy Pumps Low or erractic pressure No Pressure Actuator fails to move Slow to erratic operating Erratic Feed Rates Overheating of System Excessive slippage or internal leakage Machine Maintenance in General Pressure gauges and pyrometers Hydraulic Oil Fitters Coolers (heat exchangers) Oil leaks Troubleshooting of a hydraulic circuit Brief mould Design Check List Press Moulding Tool A checklist Mould Visa-Vis Machine Check these items for trouble free moulds Mould making using computer integrated manufacturing (CIM) CAD for Part Designing Maintenance and Care of Moulds Serving Repairs Most Common CAE AND CAD TECHNOLOGY IN MOULDS MAKING What is CAE Flow Analysis Cooling Analysis Structural Analysis Usage of CAE User Specified Values Is it not an expensive showpiece? Computer Aided Design and Computer Aided Manufacturing 2D System 3D Interactive graphics system Solid Modellers CAM Computer Aided Manufacturing How Does the Mould design software Expedite the work How does CAM Software Work Assembly and Testing of Mould INJECTION MOULDING PROCESS

5 Machine Ratings Influence of Mateial Properties on the Moulding Nozzle Runners and Gates Mould Product Design for Injection Moulding Coloured Moulding Moulding Problems Finishing and Regrinding Purging Process Control Computer Integrated Injection Moulding Microprocessor Control Systems Computerised process Simulation of 1M SPECIALISED INJECTION MOULDING PROCESS Co-Injection Moulding Two Colour Moulding Gas Injection Moulding (GIM) Advantages and Disadvantages Basic Processes and Procedures Disadvantages Processes Procedures Moulding Aspects Shrinkage Multi Live Moulding Counterflow Moulding Oscillatory Moulding for Optical Disks Reaction Injection Moulding Mould Process Controls Liquid Injection Moulding Structural Foam Moulding (SFM) Performance Plastic Materials Characteristics of foam Design Analysis Blowing Agents Methods of Processing structural Foam (SF) with Chemical Blowing Agents (CBA) Low pressure foam High pressure foam Processing SF with Gas blowing Agent Tooling Startup for Moulding Tandom Processing Systems Tandem Moulding Machines Operational sequence Coining Injection Blow Moulding (IBM) Injection Moulding with Rotation

6 DIP Injection Blow Moulding Materials Metal Injection Moulding (MIM) Ceramic Injection Moulding Fusible and Soluble Core Moulding Vacuum Moulding TROUBLESHOOTING IN INJECTION MOULDING Problem of Short Shots Problem of Flashing Problems of Bubbles and Voids Problem of Brittleness of Component Problem of Discoloration Problem of silver streaks Problem of Nozzle Drooling and Foaming Problem of Scorching Problem of Sprue Sticking Problem of Surface Lamination Problem of Parts Sticking of the Muld Problem of Surface Waviness (Pits, Orange peel, Wrinkles) Problem of Warping Problem of Weld Lines Problem of Dimensional Variation Problem of Jetting Problem of Gate Smear Technological Solutions for Total Quality in Injection Moulding of Plastics Machine Mould Material Man Quality Related Problems Problems of Moulding Perfect Mouldability INJECTION MOULDING OF THERMOSETS Process Operations Process and Design Considerations Materials Process Effects on Design Injection compression Moulding Part Design Consideration Cold Runner Moulding Injection Moulding Reinforced Polyesters Injection Moulding Presses Temperature Control INJECTION MOULDING MACHINE

7 Co-Injection Moulding Process Equipment Reaction Injection Moulding (RIM) Low Pressures Low Temperature Liquid Intermediates Equipments Material Conditioning System Matering System Mixing head Mould Carrier Tooling DESIGN FOR INJECTION MOULDS Mould Design Features Two Plate Mould Three plate Mould Hot Runner Moulds Insulated Runner Moulds Runners Gates Venting Parting Line Ejection Ejector Mechanisms Ejector Sleeve Stripper Ring Stripper Plates Vent Pins Cam Actions Early Ejector Hetum Unit Mould Cooling Standard Equipment Standard Mould Bases Standard Cavity Inserts DESIGNING MOULDS FOR THERMOSET PROCESSING Method of Moulding Transfer Moulds Injection Moulding of Thermosets Injection Compression Moulding of Thermosets Runner and Gate Design Vents General Mould Design Considerations

8 INJECTION MOULDED PLASTIC COMPONENTS Manufacturing Process Plasticizing Process Flow Sheet Plant Economics of Injection Moulded Plastic Components Rated Plant Capacity Land and building Plant and Machinery Fixed Capital Raw Materials Total working capital/month Total Capital Investment Turn Over/Annum profit Sales Ratio Rate of Return Break Even Point PLASTIC MOULDED TOYS Process of Manufacture Injection Moulding Process in Detail Plasticizing Injection After filling Process flow sheet Plant Economics of Plastic Mould Toys Rated Plant Capacity Land and building Plant and Machinery Fixed Capital Raw Materials Total working capital/month Total Capital Investment Turn Over/Annum profit Sales Ratio Rate of Return Break Even Point PLASTIC INJECTION MOULDING PRODUCTS Process of Manufactures Plant Economics of Plastic Injection Moulding Rated Plant Capacity Land and building Plant and Machinery Fixed Capital Raw Materials Total working capital/month

9 Total Capital Investment Turn Over/Annum profit Sales Ratio Rate of Return Break Even Point PLASTIC INJECTION MOULDING ITEMS (LIKE BUCKET, PLASTIC CHAIRS, BATHING TUB) Manufacturing Process Plasticizing process Flow Sheet Plant Economics of Plastic Injection Moulding Rated Plant Capacity Land and building Plant and Machinery Fixed Capital Raw Materials Total working capital/month Total Capital Investment Turn Over/Annum profit Sales Ratio Rate of Return Break Even Point