K2004 Plastics International Trade Fair

Düsseldorf, Germany 20th - 27th October 2004

Thermoplay (Hot Runner Systems) - Exhibition Hand-out


Thermoplay’s Hot Runner System

Integrated into

Indestep’s Rotary Injection Moulding



Thermoplay has combined the company's expertise in hot runner system design for special applications with the patented design of the Indestep International 8 station rotary injection moulding machine. The result is a unique machine with an injection unit that has an integrated hot runner system that allows direct injection into the cavity or cavities without the need of a hot runner in each mould. Major benefit is substantially reduced tooling costs as the hot runner is purchased just once with the moulding machine with further savings achieved by the use of standard base plates on the rotary table allowing the use of interchangeable cavities.


Chief Executive and owner of Indestep, David Brent, approached a number of hot runner manufacturers with a view to forming a strategic alliance to complete the development of the machine of which the integrated hot runner is a major feature.  Eventually Thermoplay were chosen as the company able to provide the hot runner knowledge and to contribute to some of the design features of the machine.


Indestep chose the rotary machine concept to take advantage of the multiple functions that can take place at the same time at different stations such as printing and insert moulding combined with the well known advantage of reduced cycle time when cooling is the major proportion of the moulding cycle.   (The machine includes a central rotating cooling system.)  The addition of a second injection unit at another of the 8 stations for two material moulding makes the machine a competitive alternative to conventional injection moulding machines for such applications as dual material caps and closures and medical parts, cosmetics - three of the company's target markets.


Any of the Thermoplay’s range of hot runner manifolds and injection bushings can be integrated with the machine's injection units including valve gate, 240 volt externally heated open flow bushings. It also allows the KS5 multi tip nozzle for direct feeding of individual parts to be used.   We can also use the KS8 edge gate bushing. This allows the type of injection bushings used at each injection station to be determined by the application. For example, valve gate bushings would be fitted at the station moulding TPE for soft touch and sealing applications with conventional thermal break bushings used at the station moulding the base material.


Technical parts and value added mouldings such as printed and insert mouldings are envisaged as prime markets for the machine as robotics can be readily positioned at the stations for placement of inserts, pre-printed film or foil and for removal of mouldings. For Technical moulding reinforced engineering thermoplastics are generally used dictating the use of Thermoplay’s titanium nitride treated injection bushings to minimise the wear problems associated with such materials.


Initial models of the machine that are expected to be available in the first quarter of 2005 will be in the range of 50 tons and as the design is modular there is the facility to supply standard and customized versions.  This ability combined with the unique injection system, the advantages of the rotary table and a fast table indexing speed makes the machine a flexible and viable economic alternative to conventional high speed injection moulding machines.