Intermediate flange blocking flap, Pneum. actuation drive, DN 50 - Riegler 103668

Intermediate flange blocking flap, Pneumat. actuation drive, double-acting, Operating temp. -15°C to 120°C, DN 50, PN max. 16 bar Butterfly valves with pneumatic actuator. Pneumatic actuators, double- or single acting version. For water/steam, seawater, salt water, ester, ketones, alkalis, caustic soda, sodium hydroxide. Not recommended for hydrocarbons, oils or greases.

Standards and origin

• Customs tariff number: 84818081
• Country of origin: DE

About Butterfly valves

Butterfly valves shut off large-bore pipework and need far less face-to-face length and weight than a gate valve. The group covers DN 40 to 300 mm at operating pressures of 10 to 16 bar. Some versions are hand-operated, others carry a pneumatic quarter-turn actuator.

What matters when choosing

• DN 40 to 300 mm follows the pipe. For the wafer type also check the flange drilling standard used in the plant.
• Seat material EPDM, EPT or FKM: EPDM and EPT suit water, steam and alkaline media, FKM is the choice when the medium is too aggressive for the ethylene propylene grades.
• Double-acting or single-acting spring-to-close: single-acting drives itself into the closed position if control pressure fails, double-acting holds the last commanded position.
• Body material: grey cast iron GG25, epoxy-coated GG25 in RAL 5015 or ductile iron GGG50. The coating pays off in damp surroundings, GGG50 under higher mechanical load.
• Operating temperature and pressure: released for -15 °C to 120 °C and PN max. 10 to 16 bar. Both have to match the design point of the line.

Typical applications

• Water and steam lines in building services and plant engineering
• Sea water and salt water circuits, with the seat quality chosen accordingly
• Cooling water distribution to machines and heat exchangers
• Process lines carrying alkalis, caustic soda, esters or ketones
• Automated shut-off points where the pneumatic actuator replaces manual operation

Depending on the item the seat is EPDM, EPT or FKM and the body is grey cast iron GG25 or ductile iron GGG50. These valves are not recommended for hydrocarbons. Manufacturing takes place in Germany and China.