Diversified Plastics of Minneapolis moulded the Peek components, said Diversified Vice President Annette Lund.
“Southwest Research Institute approached us to produce the plastic components because of our expertise with high-performance thermoplastics and our willingness to produce high-precision, small-quantity parts,” said Lund. “The customer’s specifications included using polyetheretherketone and we have experience moulding this thermoplastic material for our medical-device customers.”
Peek was chosen because it is stiff, strong and lightweight, said Southwest Research design engineer Chip Beebe in a telephone interview. It also has a low outgassing profile compared with most plastics exposed to the high vacuum of space, he added.
One part required moulding Peek around an aluminium ring and the other needed multiple aluminium inserts that were first machined and then press-fit into the moulded plastics.
“We were able to perform all the operations in-house, saving our customer time and money,” Lund said.
Diversified’s willingness to maintain a low Peek inventory and to do very short runs in the job helped it capture the contract, Lund said. Not counting the cost of building moulds, the project only grossed about $15,000.
The parts measure 5-7 inches in diameter. They were moulded in single-cavity tools at mould temperatures of about 700° F, the company said. Diversified used unreinforced Peek from Thornton Cleveleys, England-based Victrex plc, and 30 percent glass-reinforced, high-flow Peek from RTP of Winona, Minn.
The unreinforced part was chosen as an electrical shield to prevent arcing, Beebe said. The reinforced part has a structural function. Peek is also resistant to ultraviolet radiation in the sun’s rays.
The space probe was launched in August 2011 and is expected to begin orbiting Jupiter in early July 2016.
Diversified recently became an employee-owned firm. Lund said it boasts a higher-than-average ratio of women in management positions.
