Case Study: Turbulent flow temperature control cuts cycle times

Injection moulding specialist, Warden Plastics, says by fitting temperature control units on two of its highest output machines it has both stabilised its process and accrued “significant” financial savings by shaving 10 percent off cycle times.

The Luton-based company, which provides contract manufacturing of extruded and injection moulded parts and products to the automotive, electronics, medical, construction, point of sale and vending industries, also produces its own range of biological filter media. One of these products, the Biomarble, is a spherical polypropylene filter used in industrial and municipal wastewater treatment plants.

To keep pace with rising demand for these filters, Warden Plastics upgraded the moulding tool on its Sumitomo Systec 160-tonne machine from an eight-impression to a 16-impression tool in September 2013. The increase in cavities meant more heat was entering the tool, necessitating increased mould temperature control in order to maintain a stable process at high speed.

“As more heat was entering the process, we were unable to run the tooling for any length of time due to overheating. Because of the size of the tooling and the speed of the cycle we needed a temperature controller with more powerful flow and heat transfer capabilities,” commented Mark Barrett, Managing Director of Warden Plastics.

The company fitted two AEC TrueTemp TCU 300 9kW water temperature control units on the mould, which are designed to promote turbulent water flow to maximise heat transfer performance, said to deliver more efficient and effective control than indirect cold water systems.

Since installing the units, Warden Plastics reports that it is able to run a stable process, producing a consistent, repeatable product with zero defects. In addition, the TCUs are said to have shaved a second off the cycle, reducing cycle time from 12 to 11 seconds.

“When calculated across 5,236 units per hour on a 24 hour operation, this represents a considerable cost saving. We expect the TCUs will pay for themselves within a year,” said Barrett.

“All injection moulding machines use some form of basic temperature control, but the advantages of optimising this operation are often overlooked. Anyone wanting to improve process control and reduce cycle can benefit from a TCU – whatever their product or industry,” explained Nick Smith, Processing and Training Manager at Sumitomo.