Raschig offers a variety of fixed valves with large and small size (minivalves). Like the float valves, the fixed valves units cover the orifices and direct the vapor stream more horizontally than vertically into the liquid. As the width of the fixed valve legs are not the same, there is a push effect to the liquid by the outstreaming gas. This “gas driven fluiddynamics” enhances the capacity of the fixed valve tray.
Valve trays have large capacities and can realize good separation efficiencies over wide operating ranges. Fixed valves are a cost-effective solution for various applications with medium operating range, even for corrosive systems. Large fixed valves produce relatively low pressure drops, yet show a low weeping tendency. The use of smaller-sized minivalves clearly augments tray capacity.
Valve Types
R-MV
Fixed minivalve with a unique, domed cover. Net rises of 3.5 to 5.5 mm. Higher capacity compared to conventional sieve or valve trays. Applicable for 2.0 mm material thickness. Excellent pressure drop, entrainment and weeping characteristics. FRI tested.
R-RV
Round, fixed minivalve. Net rises of 4.5 to 8.0 mm. Applicable for 2.0 to 2.5 mm material thickness. Good pressure drop, entrainment and weeping characteristics.
R-FV
Trapezoid, standard fixed valve. Net rises of 4.5 to 11.0 mm. Applicable for 2.0 to 3 mm material thickness. Versatile, good pressure drop and capacity performance.
R-LV
Round, large fixed valve. Net rises of 5 to 11.0 mm. Applicable for 2.0 to 3 mm material thickness. Low pressure drop, robust, used in fouling services.