Custom Manufacturer of Fabric Reinforced Diaphragm Seals. +200 years of combined technical experience. Supplying industrial users around the globe for over 50 years, RPP diaphragm seals are used in a wide range of industrial and scientific equipment. Primary markets include Process Control Valves, Agriculture & Water Management, LPG and Natural Gas Regulators, Nuclear, Medical Devices and Industrial Systems. RPP can solve your most challenges in-field demands and makes some of the largest fabric reinforced diaphragms on the market.