vii Contents 1 Principles of Mold Design Types of Injection Molds Types of Runners and Gates 1.2.1 Solidifying Systems 1.2.2 Hot Runner Systems 1.2.3 Cold Runner Systems 1.2.3.1 Molds for Processing Elastomers 1.2.3.2 Molds for Processing Thermosets 1.3 Temperature Control in Injection Molds 1.4 Types of Ejectors 1.5 Types of Undercuts 1.6 Special Designs 1.6.1 Molds with Fusible Cores 1.6.2 Prototype Molds of Aluminum 1.6.3 Prototype Molds Made of Plastics 1.7 Status of Standardization for Injection Molds 1.7.1 Standardized Mold Components (as of Mid-2005) 1.7.2 Standardized Electrical Connections for Hot Runner Molds 1.7.3 Terminology Standards for Injection Molds 1.7.3.1 DIN IS0 12165 “Tools for Molding-Components of Compression and Injection Molds and Die-Casting Dies” 1.7.3.2 DIN 16769 “Components for Gating Systems Terms” 1.7.4 DIN IS0 16916 “Tools for Molding - Tool Specification Sheet for Injection Molds” 1.8 Standard Mold Components 1.9 Injection Mold for Producing Test Specimens hom Thermoplastic Resins 1.10 Materials Selection 1.10.1 General Requirements for Materials 1.10.2 Tool Steels 1.10.2.1 Case-Hardening Steels 1.10.2.2 Prehardened Steels 1.10.2.3 High-speed Steels 1.10.2.4 Corrosion Resistant Steels 1.10.2.5 Powder-Metallurgical (PM) Steels 1.10.2.6 Cast Ferrous Materials 1.10.3 Non-Ferrous Metals 1.10.3.1 Aluminum Alloys 1.10.3.2 Titanium Alloys 1.10.3.3 Copper Alloys 1.10.4 Anorganic Nonmetallic Materials 1.10.4.1 Ceramic Materials 1.10.5 Surface Treatment Methods 1.10.5.1 Nitriding 1.10.5.2 Carburizing 1.10.5.3 Hard Chrome Plating 1.10.5.4 Hard Nickel Plating 1.10.5.5 Hard Materials Coating 1.11 Materials Properties under Mechanical Stress 1.11.1 Notch Effect under Static Stress 1.11.2 Notch Effect under Dynamic Stress 1.12 Thermal Insulation and Reflector Plates References in Chapter 1.1 1.2 ~ Special Design Features of the Example Molds 2 10 10 11 14 16 18 18 18 18 19 19 20 20 20 20 21 22 22 22 23 23 24 24 24 26 26 27 27 27 27 28 28 29 29 29 30 30 30 30 31 32 32 33 34 35 37 viii Contents Examples 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 3.21 3.22 3.23 3.24 3.25 3.26 3.27 3.28 3.29 3.30 3.31 3.32 3.33 3.34 3.35 3.36 3.37 3.38 3.39 3.40 3.41 3.42 3.43 3.44 3.45 3.46 Single-Cavity Injection Mold for a Polyethylene Cover Two-Cavity Injection Mold for Elbow Connector Made from PA 66 Injection Mold for the Body of a Tape-Cassette Holder Made from High-Impact Polystyrene Five-Cavity Injection Mold for Tablet Tubes Made from Polystyrene Four-Cavity Injection Mold for a Polyamide Joint Element Mold Base with Interchangeable Inserts to Produce Standard Test Specimens Two-Cavity Rotary Core Mold for a Polyacetal Pipe Elbow Hot Runner Injection Mold for Car Front Fender Injection Mold for Magnifying Glass Frame with Handle 16-Cavity Hot-Runner Mold for Cover Caps with Segmented Internal Contours Made from Polypropylene (PP) or Polyethylene (PE) Four-Cavity Injection Mold for a Housing Made from Acrylonitrile-Butadiene-Styrene(ABS) Four-Cavity Injection Mold for a Nozzle Housing Made from Polyamide Single Split Cavity Mold for a Threaded Plug Made from Polyacetal (POM) Demolding a Polyethylene Container with External Undercuts Injection Mold with Reduced Opening Stroke for Milk Crates from Polyethylene Two-Cavity Injection Mold for Recessed Refrigerator Handles Made from Polyamide Injection Mold for a Grass Catcher Made from Polypropylene Injection Mold for Hose Connectors Made from Polyamide 6.6 Two-Cavity Injection Mold for the Coil Form of an Auxiliary Relay Single-Cavity Hot-Runner Mold for Business Card Boxes Made from Polypropylene 8-Cavity Injection Mold for Threaded Rings Made from Polyacetal (POM) Mold for a Pump Housing and Pump Piston Made from Polyacetal Hot-Runner Injection Mold for Two Film Spools Made from High-Impact Polystyrene Injection Mold for an Angle Fitting from Polypropylene Mold for Bushings from Polyamide with Concealed Gating Injection Mold for the Valve Housing of a Water-Mixing Tap Made from Polyacetal Mold for a Lid with Three Threads Made from Polyacetal Two-Cavity Injection Mold for Coupling Sleeves Made from Polyamide Injection Mold for the Housing of a Polypropylene Vegetable Dicer Two-Cavity Injection Mold for a Polypropylene Toy Tennis Racket Two Injection Molds with Two-step Ejection Process for Housing Components from Polycarbonate Injection Mold for a Polypropylene Container with a Threaded Neck Three-Plate Injection Mold with Stripping Device for a Precision Magazine 6-Cavity Metal-Powder Injection Mold (MIM) for Transport Fasteners Mold for a Polyamide V-Belt Pulley x 8-Cavity Hot-Runner Stack Mold for Yoghurt Cups Made from Polypropylene x 2-Cavity Stack Mold for Covers Made from Polypropylene x 5-Cavity Stack Mold for Cases Made from Polypropylene 16-Cavity Hot-Runner Mold for Packaging of Medical Parts made from Polypropylene Hot-Runner Stack Mold for a Water Distribution Block Made from Polypropylene x 8-Cavity Stack Mold for Lozenge Box Made from Polystyrene Two-Cavity Injection Mold for a Tail Light Housing Made from ABS x 2-Cavity Stack Mold with a Hot-Runner System for Runnerless Molding of Polystyrene Container Lids Using Direct Edge Gating x 4-Cavity Hot-Runner Stack Mold for Dessert Cups Made from Polypropylene Hot-Runner Mold for Bumper Fascia Made from Thermoplastic Elastomer Four-Cavity Hot-Runner Mold for Threaded Covers Made from SAN 41 41 43 46 48 50 52 54 58 60 62 64 66 68 70 70 72 75 77 79 81 83 85 87 90 90 91 93 95 97 101 103 107 109 111 113 115 117 119 123 126 131 134 138 142 144 146 Contents 3.47 3.48 3.49 3.50 3.51 3.52 3.53 3.54 3.55 3.56 3.57 3.58 3.59 3.60 3.61 3.62 3.63 3.64 3.65 3.66 3.67 3.68 3.69 3.70 3.71 3.72 Two-Cavity Hot-Runner Mold for Trim Bezels Made from ABS Four-Cavity Hot-Runner Mold for Control Flap Made from Polyacetal Copolymer 64-Cavity Hot-Runner Mold for Seals Made from Thermoplastic Elastomer (TPE) Eight-Cavity Hot-Runner Mold for PP Toothpaste Dispenser 2-Cavity Hot-Runner Mold for Polyethylene Jars Two-Cavity Hot-Runner Mold for Production of Connectors Made from Polycarbonate Four-Cavity Hot-Runner Unscrewing Mold for Cap Nuts Made from Polyacetal (POM) Four-Cavity Hot-Runner Mold with a Special Ejector System for a Retainer Made from Polypropylene Example 55, x 16-Cavity Two-Component Injection Mold for Microswitch Covers Made from Polyamide and Thermoplastic Elastomer 32-Cavity Hot-Runner Mold for Production of Packings Made from Polyethylene 12-Cavity Hot-Runner Mold with Edge Gates for Bushings Made from Polyacetal Copolymer Single Injection Mold for Sleeves Made from Glass-Fiber and Talcum Reinforced PA 66 Two-Component Injection Mold for Drink Can Holders Made from Polypropylene and Ethylene-Propylene Terpolymer Hot-Runner Mold for Polypropylene Clamping Ring with Internal Undercut around the Circumference Injection Mold for Compact Discs Made from Polycarbonate Single-Cavity Injection Compression Mold for a Cover Plate Made from Unsaturated Polyester Resin Two-Cavity Injection Compression Mold for a Housing Component Made from a Thermosetting Resin Injection Compression Mold for a Plate Made from Melamine Resin Five-Cavity Unscrewing Mold for Ball Knobs Made from a Phenolic Resin Four-Cavity Injection Mold for a Thin-Walled Housing Made from a Phenolic Resin Thermoset Injection Mold for a Bearing Cover Made from Phenolic Resin 6-Cavity Hot-Runner Mold for Coffee Cup Covers Made from Polypropylene Two Injection Molds for Overmolding of Polyamide Tubing for Automobile Power Window Operators Single-Cavity Injection Mold for a Housing Base Made from Polycarbonate Connector with Opposing Female Threads Made from Glass-Fiber-Reinforced Polyamide Cylindrical Thermoplastic Container with Reduced-Diameter Opening A Study in Part Release Single-Cavity Injection Mold for a Lighting Fixture Cover Made from Polymethylmethacrylate (PMMA) Injection Mold for a Housing with a Thread Insert Made from Polycarbonate Mold for Long, Thin, Tubular Parts Made from Polystyrene Insulated Runner Mold for Three Specimen Dishes Made from Polystyrene Single-Cavity Injection Mold for a Polypropylene Emergency Button Eight-Cavity Injection Mold for Battery Caps with Undivided External Thread and Sealing Cone Made from Polypropylene Injection Mold for a Curved Pouring Spout Made from Polypropylene Injection Mold for an ABS Goggle Frame 4-Cavity Hot Runner Mold for Front Ring Two-Cavity Two-Component Injection Mold for a PC/ABS Bezel with a PMMA Window Two-Cavity Injection Mold for Runnerless Production of Polycarbonate Optical Lenses Injection Mold with Hydraulic Core Pull for a Cable Socket Four-Cavity Injection Mold for Pipets Made from PMMA Two-Cavity Mold for Water Tap Handles Made from PMMA Two-Cavity Injection Mold for the Automatic Molding of Conveyor Plates onto a Wire Cable 20-Cavity Hot-Runner Mold for Producing Curtain-Ring Rollers Made from Polyacetal Copolymer ~ 3.73 3.74 3.75 3.76 3.77 3.78 3.79 3.80 3.81 3.82 3.83 3.84 3.85 3.86 3.87 3.88 ix 148 150 152 154 156 159 161 163 167 171 173 175 177 180 183 185 187 189 190 191 194 196 200 202 204 206 208 210 212 214 216 218 220 222 224 227 229 23 233 235 237 239 x Contents 3.89 Injection Mold with Attached Hydraulic Core Pull for Automatic Measuring Tubs Made from PC 3.90 48- and 64-Cavity Hot-Runner Molds for Coating Semi-finished Metal Composite with Liquid Crystalline LCP Polymer (Outsert Technology) 3.91 24-Cavity Hot-Runner Injection Mold for Polyacetal Spool Cores 3.92 Two-Cavity Hot-Runner Mold for Loudspeaker Covers Made from Polyacetal 3.93 Injection Mold with Air Ejection for Polypropylene Cups 3.94 Molds for Manufacturing Optical Lenses Made from PC 3.95 Two-Cavity Injection Mold for a Polycarbonate Steam Iron Reservoir Insert 3.96 Injection Mold with Pneumatic Spme Bushing for a Headlight Housing Made from Polypropylene 3.97 Injection Mold for a Mounting Plate (Outsert Technique) 3.98 Twelve-Cavity Hot-Runner Mold for a Polyphthalamide (PPA) Microhousing 3.99 Two-Cavity Injection Mold for Handle Covers Made from Glass-Fiber-Reinforced Polyacetal 3.100 Four-Cavity Injection Mold for Thin-Walled Sleeves Made from Polyester 3.101 Injection Mold for a Microstructure Made from POM 3.102 Injection Mold for Production of Adjustable Climate Control Vents via 3-Shot Molding 3.103 Two-Cavity Hot-Runner Injection Mold for an ABS Cover 3.104 Six-Cavity Injection Mold for Retaining Nuts Made from Polyamide with Metal Inserts 3.105 Single-Cavity Injection Mold for a Switch Housing Made from Polyacetal 3.106 Single-Cavity Injection Mold for a Snap Ring Made from Polyacetal 3.107 Single-Cavity Hot-Runner Injection Mold for High-Density Polyethylene (PE-HD) Trash Can Lids 3.108 Single-Cavity Hot-Runner Injection Mold for an Air Vent Housing Made from Acrylonitrile Butadiene Styrene (ABS) 3.109 Single-Cavity Hot-Runner Injection Mold for an ABS Housing 3.110 Single-Cavity Runnerless Injection Mold for a Polystyrene Junction Box 3.1 11 Four-Cavity Hot-Runner Injection Mold for a Polyamide 6,6 Joining Plate 3.1 12 x 4-Cavity Hot-Runner Stack Mold for Hinged Covers 3.1 13 16-Cavity Mold with Cold-Runner System for Liquid Silicone Rubber (LSR) Caps 3.114 Two-Cavity Injection Mold for a Styrene-Acrylonitrile Safety Closure 3.1 15 Four-Cavity Unscrewing Mold for Threaded Polypropylene Closures 3.116 Four-Cavity Injection Mold for Polyester Dispenser Heads 3.1 17 Two-Cavity Injection Mold for PMMA Lighting Fixture Cover 3.118 Two-Cavity Injection Mold for Polyacetal Hinges 3.1 19 Eight-Cavity Injection Mold for PE-HD Threaded Caps 3.120 4-Cavity Hot-Runner Mold for Connectors Made from Polystyrene 3.121 Single-Cavity Mold for a Polypropylene Cutlery Basket 3.122 Two-Cavity Injection Mold for Cover Plates Made from Polyacetal 3.123 Single-Cavity Injection Mold for a Joystick Baseplate Made from PA 66 3.124 Single-Cavity Injection Compression Mold for Thermoset V-Belt Pulley (Injection Transfer Mold) 3.125 16-Cavity Hot-Runner Mold for Paperclips Made from ABS 3.126 Single-Cavity Injection Mold for a PE-HD Clothes Hanger Produced via Gas-Assisted Injection Molding 3.127 Single-Cavity Injection Mold for a Syringe Shield Produced via Metal Injection Molding (MIM) 3.128 Three-Station Mold for a Handtool Handle Made &om PP/TPE 3.129 Four-Cavity Injection Mold for Couplings Produced via Metal Injection Molding (MIM) 24 243 247 249 25 253 255 258 26 263 265 268 270 272 27 278 280 282 284 287 290 292 294 296 298 300 302 304 306 308 310 312 314 318 320 323 325 327 329 33 334