“Largest IMM in Switzerland” ticks big boxes for pipe producer
A manufacturer of piping systems based in Switzerland is producing XXL pipefittings on what is said to be the “largest injection moulding machine” in the country.
The MXH 3200-101.000/101.000 machine from KraussMaffei, which has a clamping force of 32,000 kN, a maximum shot weight of 120 kg and a screw diameter of 2 x 265 mm, was installed at GF Piping Systems in late 2014 and manufactures pipe fittings with a diameter of up to 500mm.
“A large machine with these values in this combination is unique on the market," explained Bruno Schleiss, Managing Director of KraussMaffei Schweiz AG, who said the opportunity to develop the new machine for GF allowed it to prove its expertise in the manufacture of large injection moulding machines.
An IR KR500 L340 industrial robot is also used on the machine to ensure reliable handling of the pipe fittings, which can weigh up to 120 kg. This is another record, according to KraussMaffei, because—with a maximum payload of up to 340 kg—this is the largest industrial robot that has ever been installed on an injection moulding machine.
"The investment and implementation of a new injection moulding system on this order of magnitude was certainly a special challenge for us. In addition to the technical parameters, such as a high shot weight and high quality at every point, the system had to meet other criteria with regard to the flexibility in selecting materials and geometry," explains Claude A. Fischer, Head of Business Unit Utility at GF Piping Systems.
KraussMaffei says a special challenge during the design process was the high-viscosity polyethylene 100 material that GF is using on the large machine. The solution involves optimised screw geometries and drives for the plasticising unit, which are specially designed for processing demanding material. "The controlled melt temperature during plasticising prevents the melt from overheating during the plasticising, preventing thermal decomposition of the material as a result. At the same time, a high plasticising output with outstanding melt qualities is possible," Schleiss commented.
The machine is equipped with two injection units that can be interconnected as needed, which KraussMaffei says offers increased flexibility with regards to material, size and geometry when producing the pipe fittings. "We offer our customer, GF Piping Systems, use of a shot weight they can freely choose from 5 to 120 kg, thereby providing maximum flexibility on a large machine," Schleiss added. Furthermore, each injection unit can be operated independently. This results in high application-specific flexibility in the process control.
The adapter modules of the plasticising unit provide additional flexibility in the production of pipe fittings. For example, GF Piping Systems can install a smaller SP 33000 injection unit; this makes it possible to quickly change to production with other materials. What makes this so special, says KraussMaffei, is that the material and melt geometry are perfectly matched to one another.
The IR KR500 L340 industrial robot used has an additional axis for linear motion (7th axis), provides additional freedom of movement and more flexibility as a result, especially when handling heavy components. The special gripper technology permits precise interaction of removing and gripping. The multifunctional gripper is designed for the various nominal diameters of the fittings. A special padding on the jaws protects the fittings from getting damaged.
BluePower Servo Drive Technology from KraussMaffei is utilised to support an energy-efficient manufacturing process. For the optimisation of hydraulic drives, it uses the high dynamics of servomotors to adapt the rotational speed of the hydraulic system pump to constantly adapt to the actual requirements. The same dynamics are used to reduce idling losses to almost zero by reducing the speed, such as during cooling times and during demolding. As a result, KraussMaffei says the energy consumption of the machine can be “significantly reduced.”