High pressure High-pressure pumps and vessels were more economical and reliable when introduced steam power. High-pressure pumps were used at 500 to 800 PSI High-pressure systems were further developed by the oil industry, aviation, and automobile. Automotive designers did similar research for hydraulic suspension systems. The invention of seal technology and the rise of plastics in the postwar years led to the development of the first high-pressure pump. This was the basis for waterworks' commercial success. A design that was improved in 1976 by Flow Industries.