General Machinery & Manufacturing Co

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Stephen Junkunc II founded GMMCO in 1918, realizing a dream of owning his own machine shop. Stephen progressed into manufacturing metal stampings for casket hardware. With the outbreak of World War II, GMMCO converted the shop for the war effort and began manufacturing various aircraft parts, including B-29 hydraulic spools on behalf of Ford Motor Company, who was sub-contracting work from engine maker Pratt & Whitney.GMMCO's quality and service was so dependable that Pratt & Whitney asked GMMCO to manufacture a critical fuel nozzle seal for JT3 turbofan and J57 turbojet - the world's first jet engine to develop 10, 000 lbs. of thrust and the power-plant for the B-52 Stratofortress.Since then, GMMCO went on to design many other types of unique fuel nozzle seals for Pratt & Whitney, including our signature "knife-edge seal". Many years and millions of seals later, GMMCO seals and related parts are being used on many military, commercial, and aero-derivative turbine engines.