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Explore various techniques like gluing, welding, and mechanical connections in corporate training and planning. Learn about types of bonding and limitations, advantages, and disadvantages of each method. Discover the uniqueness of welding and its principles along with different types of welding processes.
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JOINING & ASSEMBLING CORPORATE TRAINING AND PLANNING
Methods of Joining & Assembling • Gluing • Welding • Mechanical Connections CORPORATE TRAINING AND PLANNING
Functions of Joining For Permanent Joining • Gluing • Welding For Disassembly • Mechanical Connections CORPORATE TRAINING AND PLANNING
Bolted Assemblies Self Tapping Screws Snap Fits Threaded Metal Inserts Hook and Loop Type Fasteners Moulded-in-Threads Boss Cap Push-on / Turn-on Fasteners Rivets Press Fits Types of Mechanical Connections CORPORATE TRAINING AND PLANNING
The main mechanical connections used for plastic assembly CORPORATE TRAINING AND PLANNING
Types of Gluing • Solvent Bonding • Adhesive Bonding CORPORATE TRAINING AND PLANNING
Adhesive bonding CORPORATE TRAINING AND PLANNING
Solvent Bonding Advantages • Homogeneous distribution of mechanical loads • Good aesthetics • Economic assembly • Low weight, no heavy screws, bolts and nuts • Heat sensitive constructions or materials, which welding would distort or destroy, can be joined • Good sealing and insulating properties. CORPORATE TRAINING AND PLANNING
Solvent Bonding Limitations • Entrapment of solvent in the joint • Stress cracking or crazing • Dissimilar materials can only be joined if both are soluble in a common solvent or in a mixture of solvents • Differences in thermal expansion of components are not compensated if dissimilar materials are bonded • Reproducibility/process control • High solvent evaporation time due to its entrapment in the polymer matrix • No disassembly possible • Assembly hazards such as fire or toxicity. CORPORATE TRAINING AND PLANNING
Adhesive Bonding Advantages • Application on various substrates like thermoplastics, thermosets, elastomers and metals • Homogenous distribution of mechanical loads • Differences in thermal expansion of components can be compensated for by using a thick adhesive layer • Good aesthetics / no special requirements to hide the bond. • Economic assembly • Low weight, no heavy screws, bolts and nuts • Heat sensitive constructions or materials, which welding would distort, can be joined • No thermal stresses introduced • Good sealing and insulating properties. CORPORATE TRAINING AND PLANNING
Adhesive Bonding Limitations • Long term behavior may not be very good • Stress cracking or crazing of the plastic may take place • Dissimilar materials can only be joined if both are compatible with the adhesive • Reproducibility/process control • Curing time can be high depending on the adhesive • No disassembly possible • Assembly hazards such as fire or toxicity CORPORATE TRAINING AND PLANNING
Welding An effective method of permanently joining plastics components together. CORPORATE TRAINING AND PLANNING
Welding Principle • Inter diffusion of Molecular Chains • Phase Change from Solid to Liquid. • Followed by Solidification Phase at the Interfaces to be joined together. CORPORATE TRAINING AND PLANNING
Uniqueness of Welding • Good Aesthetics • Clean • Strong Bond CORPORATE TRAINING AND PLANNING
Schematic representation of the welding process CORPORATE TRAINING AND PLANNING
Vibration welding Spin welding Ultrasonic welding Hot-plate welding Induction welding Laser welding Radio freq. welding Resistance welding Hot gas welding Staking Types of Welding CORPORATE TRAINING AND PLANNING
Vibration Welding • the two plastic parts to be joined are vibrated (rubbed) against each other at a certain frequency, amplitude and pressure which results in frictional heating of the surfaces, causing the polymer to melt at the interface. • The molten polymer flows out of the weld-zone giving rise to flash. When vibration stops, the weld cools down and solidifies. CORPORATE TRAINING AND PLANNING
Vibration welding process CORPORATE TRAINING AND PLANNING
Vibration welding equipment CORPORATE TRAINING AND PLANNING
Advantages of Vibration Welding • Cost Effective • Short Cycle Times • Large Batch Sizes Possible • Melted Polymer Not Exposed to Open Air • Strong Bond CORPORATE TRAINING AND PLANNING
Disadvantages of Vibration Welding • Welding Thermoplastic Elastomers is problematic. • Product is exposed to vibrations during welding. • Much flash is formed. • 3D Contours can’t be welded. CORPORATE TRAINING AND PLANNING
Spin Welding • The two parts to be welded are pressed against each other. • One part is held fixed and the other rotates at high speed. • The friction between the two parts generates heat which causes the polymer to melt at the interface. • The molten polymer flows out of the weld-zone giving rise to flash. When rotation stops, the weld cools down and solidifies. CORPORATE TRAINING AND PLANNING
Spin welding equipment CORPORATE TRAINING AND PLANNING
Advantages of Spin Welding • Efficient, Simple Process • Simple Equipment • Short Cycle Times • Large Batch Sizes Possible • Melted Polymer not Exposed to Open Air • Strong Bond CORPORATE TRAINING AND PLANNING
Disadvantages of Spin Welding • Welding Thermoplastic Elastomers is problematic. • Only Circular Contours can be Welded. • 3D Contours can not be Welded. • Relative Position of the Parts can not be Adjusted. CORPORATE TRAINING AND PLANNING
Ultrasonic Welding • The process uses low amplitude and high frequency vibrational energy. • Parts to be joined are fixed firmly. • Mating part is subjected to sinusoidal Ultrasonic Vibrations of the order of 20,000 cycles per second. CORPORATE TRAINING AND PLANNING
Ultrasonic welding process CORPORATE TRAINING AND PLANNING
Equipment for ultrasonic welding CORPORATE TRAINING AND PLANNING
Advantages of Ultrasonic Welding • Cost Effective • Short Cycle Times • Large Batch Sizes Possible • Melted Polymer Not Exposed to Open Air CORPORATE TRAINING AND PLANNING
Disadvantages of Ultrasonic Welding • Welding Thermoplastic Elastomers is problematic. • Product is exposed to vibrations during welding. • Restricted to Small and Medium Size parts. CORPORATE TRAINING AND PLANNING
Hot Plate Welding Uses thermal energy to melt the welding zone through conduction. CORPORATE TRAINING AND PLANNING
Hot plate welding process CORPORATE TRAINING AND PLANNING
Advantages of Hot Plate Welding • Cost Effective • Large Batch Size is Possible • Suited for Soft Materials • No Electrical Fields, No Mechanical Vibrations. • Strong Bond CORPORATE TRAINING AND PLANNING
Disadvantages of Hot Plate Welding • Long Cycle Times • Molten Polymer Expose to Open Air • Weld Strength is Poor for Certain Heat Sensitive Materials. CORPORATE TRAINING AND PLANNING
Induction Welding • Uses Inductive Energy to heat the Plastic. • The bonding material melts and the parts are joined under low pressure. CORPORATE TRAINING AND PLANNING
Induction welding process CORPORATE TRAINING AND PLANNING
Advantages of Induction Welding • Short Cycle Times. • 3D Weld Surfaces are Possible • Thermoplastic Elastomers can be welded. • Can be used for highly filled materials • Welding process is reversible (Repair, Recycling). • Tolerances on Part Dimensions not tight. CORPORATE TRAINING AND PLANNING
Disadvantages of Induction Welding • Electro-magnetic Welding gasket Material is required. • Not well suited for parts containing electromagnetic sensitive items (Metal Inserts). CORPORATE TRAINING AND PLANNING
Hot Gas Welding • Uses Hot Air or Nitrogen to Melt the Surfaces to be joined. • Process is extensively used for assembling large parts. • Suitable for field assembly and repair. CORPORATE TRAINING AND PLANNING
Hot gas welding CORPORATE TRAINING AND PLANNING
Hot gas welding process CORPORATE TRAINING AND PLANNING
MACHINING OF PLASTICS CORPORATE TRAINING AND PLANNING
Different Types of Cutting • Sawing • Laser Cutting • Milling • Turning & Boring • Punching, Blanking and Die Cutting CORPORATE TRAINING AND PLANNING
Different Types of Finishing • Filing • Sanding • Grinding • Polishing and Buffing CORPORATE TRAINING AND PLANNING
SURFACE TREATMENT CORPORATE TRAINING AND PLANNING
Uniqueness of Surface Treatment • Transforms the materials into more workable substrates. • Surface Treatment is a must before printing for non-polar materials. CORPORATE TRAINING AND PLANNING
Types of Surface Treatment • Mechanical Abrasion • Flame Treatment • Chemical Etching • Corona Treatment • Plasma Treatment CORPORATE TRAINING AND PLANNING
Different Types of Finishing • Filing • Sanding • Grinding • Polishing and Buffing CORPORATE TRAINING AND PLANNING
METALLIZATION CORPORATE TRAINING AND PLANNING
Uses of Metallization • Enhances Reflectivity • Improves Abrasion Resistance • Has High Electrical Conductivity • Provides Electromagnetic Shielding CORPORATE TRAINING AND PLANNING