Process Development & Control is a leading manufacturer of industrial butterfly valves for HVAC, furnace, power, blower and exhaust air transfer systems, in addition to special service applications. PDC offers customers a wide variety of materials for construction options and design specifications. Over 40 years of experience in design and fabrication of quality valves has gained worldwide customer acceptance and a loyal customer base. Our manufacturing experience combined with our capacity and equipment allows us to customize the individual characteristics of our valve products.