LESER Pilot Operated Safety Valves (POSVs) are designed according to the API 526 standard. The full range of sizes from 1″ x 2″ up to 8″ x 10″ (DN 25 – DN 200) with all orifices from D – T is available for pressure ratings up to pressure class 2500 x 6001). Beyond API 526, LESER offers so-called Extra Orifices (also known as Full Port or Full Bore nozzles). The Extra Orifices provide maximum capacity in relation to valve size. In addition, LESER POSVs come in two different functional designs, i.e. Pop Action (Series 810) and Modulate Action (Series 820). These designs determine the POSVs operating characteristics.