1. Home
  2. >>
  3. Injection Moulding

Injection Moulding

What Is The Process?

    Information regarding the key elements to the Injection Moulding process and why cooling is required.

  1. The raw plastic material is taken from a hopper into the extruder and is heated and forced through a nozzle to inject the plastic into the closed mould
  2. Chilled water is passed through the cooling channels in the mould to cool the plastic and solidify it quickly
  3. The hydraulic motors force oil to close and lock the mould (tonnage) and open the Mould apart to release the completed product
  4. Hot runners are electric elements that surround the plastic flow paths in the mould from the extruder to the mould cavity, these stop the plastic in the plastic runners from having to be removed when the finished part is ejected (Spru)

injection moulding

For more information about Injection Moulding, please visit the Wikipedia page which will describe the process in more detail.

Considerations: Free Cooling - Are tools changed regularly? If so glycol may not be wanted in the cooling circuit and therefore frost protection or free cooling must be separated - Are there accumulators? - Are the hot runners insulated?

Injection Mould Cooling Systems

Why is cooling required for injection mould cooling systems?

  1. To cool the mould there are cooling pass-ways in the mould, cooling water flows around these pass ways to remove the heat from the product. This transfers the heat into the water requiring cooling
  2. The hydraulic oil is pumped around the system at high pressure for all the robotic parts on the machine. The hydraulic oil heats up when the hydraulic pump runs caused by the machine cycling. The hydraulic oil passes through a heat exchanger with water passing through the secondary circuit removing the heat from the oil
  3. The hot runners add heat to the mould as they maintain the temperature of the plastic within the flow path of the mould. Some hot runners are insulated and some not, on intricate parts or very fast moulds these can be considerable in their added load

How To Calculate The Cooling

  • Tools = Plastic through put x plastic factor / kcals = Cooling Duty in KW
  • Hydraulics = 400 kcals / 1 hour x hydraulic motor size / kcals = Cooling Duty in KW
  • Hot Runners = Internally Hot Runners KW Input X 0.65 = Cooling Duty in KW
  • Externally Hot Runners KW Input X 0.8 = Cooling Duty in KW

Call Aqua Cooling Solutions Today!

Our engineers have many years experience in the plastics industry and Aqua has provided cooling solutions to major injection mould companies in the UK and overseas.

Before speaking to Aqua, please try and answer the following questions as thoroughly as possible, as the more information you can provide, the easier it will be for us to help you with your requirements:

  • What is the temperature of the chilled water required?
  • What water pressure do you require at the tools?
  • What is your plastic throughput/hour?
  • What type of plastic is being used?
  • What is the hot runner size?
  • Are the hot runners insulated?
  • Is there an accumulator fitted?
  • What is the hydraulic motor input power?

Aqua's team are ready to take your call on 0333 004 4433 should you have a requirement for an injection mould cooling system.

awards

awards

awards

awards

awards

awards