Butterfly valves are generally used where space is limited. Unlike gate valves, butterfly valves can be used for throttling or regulating flow as well as in the full open and fully closed position. By turning the stem through 90 Degrees, a disc rotates to achieve fully open or fully closed valve positions. Energization of the seat to seal interface is by the mechanical force transferred through the stem by the hand lever, however certain designs of butterfly valves also use the process pressure to assist in the energization of the seal.
Euroguarco butterfly valve product range covers construction by Concentric, Offset, Double Offset and Triple Offset type, conforming to API 609, ASME B16.34, ASTM, ANSI, EN, DIN, BS. Materials are mostly forged and cast steel or alloys.
Various optional designs are available: fire safe design, cryogenic service, sour service, stem extended, wafer pattern, lugged wafer, flanged.
A Butterfly valve is a quarter-turn rotary motion valve, that is used to stop, regulate, and start the flow. Normally, they are used in systems where a positive shut-off is not required. However, over the years, these valves have been manufactured with fairly tight seals made of rubber or elastomeric materials that provide good shut off similar to other types of valves.