Paul N. Colby
Spirex Corporation
Inducted 2009
Paul N. Colby (1929 – 2015) and his wife Illene founded the Spirex Corporation, a leader in designing and producing plasticating screws, barrels, and front-end components for plastics machinery in 1978, with company headquarters in Youngstown, Ohio. Paul Colby graduated with a degree in mechanical engineering from Princeton University in 1950. He served in the U.S. Navy during the Korean War. Following the war, he started his 60-year plastics industry career when he joined the Winner Manufacturing Company, a reinforced plastic component manufacturer. As an engineer at Winner, he designed, built, and tested various products, including a 60-foot-long floating pontoon bridge, which at the time was one of the largest reinforced plastic items ever manufactured. He left Winner to become a sales engineer for Union Carbide Corporation, where he gained experience in thermoplastic materials. This experience and interest in thermoplastics resulted in co-founding a New Jersey-based blown film manufacturing company, the Polyethylene Corporation. The blown film company failed. However, Colby learned many valuable business lessons from this venture.
Paul Colby then started his career in the plastics machinery side of the industry. His initial machinery engineering position was with Sterling Extruder Corporation. He also worked as a sales engineer selling Lombard and Farrel injection molding machines at manufacturers’ representative firm Metropolitan Machinery Corporation. He then worked at the David-Standard Corporation and the Prodex Corporation, leading extrusion equipment builders, where he supervised the national sales forces. Prodex’s parent company, Koehring Corporation, soon merged Prodex with HPM Corporation of Mount Gilead, Ohio. All these positions allowed Colby to gain a great deal of experience in plasticating technologies for extrusion and injection molding.
Colby left HPM in 1970 for a position at Feed Screws Incorporated, later known as New Castle Industries, a leading supplier of plasticating screws and barrels for plastics processing machinery. He was vice president of sales and engineering, then general manager at New Castle Industries. Colby left New Castle Industries after eight years to start the screw and barrel company, Spirex Corporation, which became a major competitor of New Castle.
Colby and Spirex pioneered many screw designs and methods for manufacturing plasticating screws. His novel screw designs included a retrofit vented-barrel conversion used in extrusion and injection molding. He also invented a portable machine that could be used to cut a grooved-feed section in a barrel on-site at a customer’s plant. He designed and patented many plasticating screw mixing sections known commercially as the Pulsar, the Flex Flight, the Z-Mixer and the V-Mixer. Spirex became an internationally known plastics machinery business that was eventually purchased by Xaloy Corporation in 2009.
Areas of Expertise:
Plastics machinery