What is Extrusion Blow Molding?

Extrusion Blow Molding produces hollow shaped articles, with the following steps:
- Resin is heated and plasticized by an extruder
- The molten resin is extruded so that it forms a tube-shaped parison matching the size of the product using the die
- The Parison is enclosed by the mold halves and the bottom is squeezed during pinch-off stage
- Air is then forced into the parison and presses it against the inner walls of the mold
- The product cools down and becomes solid in the mold, the air pressure is released
- The mold is opened and the product is transferred to post cooling and deflashing unit then taken-out by article discharge
HIPF Course Description
Course Objective
At the end of the course, the trainees will be able to:
- Develop a working knowledge of and learn how to operate a Blown Film Extrusion machine
- Understand the basics of blow molding technology, plastics behavior and common problem solving situations
- The ability to recognize processing conditions that affect quality
- The ability to analyze and solve practical blow molding problems
- Learned and understood safety practices in the workplace
Course Outline
- Introduction to Blow Molding
Molding Methods and Industry Size; Principles of Blow Molding; Types of Blow Molding; Advantages; History; Applications; Materials; Molds; Parts and Functions; Process and Operation
- Blow Molding Operation Safety Practices
Workshop Safety Practices; Proper Clothing At Work; Safety Devices; Warning Signs; Sources of Danger; Safety Instructions
- The Extrusion Blow Molding Machine
The Extrusion Blow Molding Process; Machine and Equipment Parts, Functions and Specifications; Blow Molds; 5-Media Used in Blow Molding
- Mold and Machine Maintenance
Mold Maintenance; Machine Maintenance; Machine Daily Inspection List; Care and Maintenance Schedule; Cleaning the Scrap Mill
- Extrusion Blow Molding Machine Operation
Blow Molding Machine Start-up Procedure; Shutdown Procedure; Mold Change-over and Set-up Procedure; Changing Die/Tools; Changing Materials and Masterbatch; Purging the Extruder
- Machine and Blow Molding Process Troubleshooting
Parison Defects; Appearance Defects; Container Performance Defects; General Machine Malfunctions
- Product Quality Testing
Quality and Quality Control – Definition; Classes of Product Defects; Laboratory Tests and Quality Control Test Methods; Product Quality Evaluation
- Practice Training
Orientation on Workshop Facilities and Safety Equipment; Familiarization on Parts and Functions of Machines and Equipment; Machine Operation Demonstration by Senior Instructor; Starting and Shutting Down Machine by Trainees; Machine Parameters Setting; Parison Adjustment and Optimization; Blow Pin Adjustment.
Deflasher and Article Transfer Adjustment; Product Sampling and Evaluation; Mold and Toolings Change-over and Set-up; Process and Machine Trouble Shooting; Raw Material Preparation; Changing Materials
and Masterbatch; Purging the Extruder; Scrap Mill Operation and Recycling