These pressure vacuum valves maintain a tight seal until system pressure or vacuum exceeds the set pressure. The valves allow an intake of air under constant pressure during emptying, or discharge excessive over pressure during filling of the tanks. Flow curves are provided to help you select the proper valve size for venting requirements. In addition, KSPC’s applications engineers are always available to assist you. The KSBBF is a weighted pallet model designed to handle pressure and vacuum with a minimum pressure of +/-20mmW.C and a maximum setting of + 700/-430 mmW.C High strength, one-body casting provide added structural integrity and durability. Body materials are available in Aluminium, Carbon Steel, 304SS and 316SS with various trims to suit individual requirements. Sizes range from 50mm through to 350mm with ANSI 150lb flanges as standard. (Different connections available on request). The valves have additional FM factory mutual approval for the majority of sizes and materials.