Building on a rich history that spans many industries, four companies have come together to form Matrix PDM Engineering. The original Tulsa-based engineering office has been a key contributor to the growth of Matrix Service Company, providing industry-leading expertise in aboveground storage tanks and steel plate structures. The acquisition of PDM (Pittsburgh Des Moines) brought more than 50 years of history and multi-discipline engineering services specializing in terminals, cryogenic storage applications, spheres and other steel plate structures. Another acquisition- EDC - brought over 40 years of experience of technical expertise in design and installation of material handling systems.