The Basics of a Stretch Blow Molding Machine

stretch blow molding machineHave you ever wondered if a stretch blow molding machine could benefit your business? If so, you should learn what this machine is, what it does, and why it is so valuable. Also referred to as reheat stretch blow molding, this could be the solution that you need.

 As for the machine itself, industries use it to produce bottles in various sizes and shapes. For example, this is a commonly used machine in the beverage industry for producing soda, juice, water, sports drink, and other bottles. To accomplish this, a preform, which is hollow plastic, gets fed into the machine and then preheated. As it makes its way through the process, it stretches in the axial direction, followed by getting blown into the desired shape.

 Although there are differences in the machines used for reheat stretch blow molding, the majority consists of the same equipment, including the following: 

  • Preform Feeding System – This system has a hopper, preform conveyor, orientator, and gravity rails. Also included are both steering and electric components. 

  • Preform Tilter – For producing containers made of polyethylene terephthalate (PET), the machine relies on an automated process. That means that preforms get supplied automatically to the hopper. 

  • Bottle Exit Conveyor – Based on the actual machine, this conveyor moves the bottles to the filler or to an unscrambling system. 

  • Compressor Station – Some machines have a compressor station based on screw compressors, air dryer with filter, booster, steering box, connectors, and air tanks. 

  • Water Cooling System – In some instances, machines have a water cooling system. 

Defects in Blow Molding Products 

To prevent defects in the finished stretch blow molding product, it is imperative that you use only a superior-quality machine. For the beverage packing industry, PET bottles are essential. With the stretch blow molding process, the bottles are robust and cost efficient. In addition, they boast a strong barrier against environmental characteristics. Best of all, PET bottles are reusable. 

For defect-free products, you should gain insight into the common problems and their causes. Following are just two examples of defects in blow molding products: 

  • Marbled Tint – Caused by cold stretching or overstretching. 

  • Dim Appearance – This cloud effect occurs if the temperature and cooling range exceed the set level, if the PET container heats up beyond 125 degrees Celsius, and because of improper blowing into the bottle. 

For state-of-the-art machines used for stretch blow molding, PET All Manufacturing is your most trusted source. For information about our company and available products, please visit us online or call today.