T 2549 EN Type 2422/2425 Excess Pressure Valve Self-operated Pressure Regulators Application Pressure regulators for set points from 0.05 to 2.5 bar · Valve nominal sizes DN 125 to 250 1) · Nominal pressure PN 16 to 40 Suitable for liquids, gases, and vapors up to 350 °C The valve opens when the upstream pressure rises. The excess pressure valves, consisting of a valve and actuator, control the upstream pressure to an adjustable set point. The medium pressure to be kept constant is transmitted through a control line to the diaphragm of the actuator and consequently the valve plug. Special features •• Low-maintenance, medium-controlled proportional regulators requiring no auxiliary energy •• Wide set point range and convenient set point adjustment using a nut •• Exchangeable set point springs and actuator •• Spring-loaded, single-seated valve with upstream and downstream pressures balanced by a stainless steel bellows or by a balancing diaphragm •• Reduced KVS coefficients to adapt the regulator to the operating conditions •• Standard low-noise plug · Special version with flow divider ST 1 or ST 3 for further noise level reduction. See Data Sheet u T 8081. Fig. 1: Type 2422/2425 Excess Pressure Valve Versions Type 2422/2425 Excess Pressure Valve for DN 125 to 250 Consisting of: Type 2422 Valve balanced by a bellows or a diaphragm with soft-seated plug · Body of cast iron, spheroidal graphite iron, cast steel or cast stainless steel · Type 2425 Actuator with EPDM rolling diaphragm Special versions –– With flow divider ST 1 or ST 3 for particularly low-noise operation –– With metal-seated plug –– With FKM rolling diaphragm, e.g. for mineral oils or flammable gases –– With NBR rolling diaphragm for flammable gases –– Version completely in stainless steel for nominal pressure PN 16 to 40 · Details on request Valves larger than DN 250 on request –– Actuator with two diaphragms –– With metal cover to protect the set point springs SAMSON AKTIENGESELLSCHAFT · Weismüllerstraße 3 · 60314 Frankfurt am Main, Germany Phone: +49 69 4009-

Principle of operation (see Fig. 2) The medium flows through the valve in the direction indicated by the arrow. The position of the plug (3) determines the flow rate across the area released between plug (3) and valve seat (2). The plug stem (5) with the plug is connected to the actuator stem (11) of the actuator (10). The upstream pressure p1 is regulated by the set point springs (7) and the set point adjuster (6). When relieved of pressure, the valve is closed by the force of the set point springs. The upstream pressure p1 to be controlled is tapped upstream of the valve and transmitted over...

Table 1: Technical data • All pressures in bar (gauge)

Table 3.1:  Valve balanced by a diaphragm · KVS coefficients and max. perm. differential pressures Δp Type 2422 Valve, balanced by a diaphragm KVS coefficients and max. permissible differential pressures Δp Nominal size Max. perm. differential pressure Δp Dimensions Type 2422 Valve balanced by a bellows L H2 Type 2422 Valve, balanced by a bellows H1 Fig. 3: Dimension diagram of Type 2422 Valve balanced by a bellows with Type 2425 Actuator Table 4:  Dimensions in mm and weights · Type 2422 Valve balanced by a bellows · The values in parentheses apply to temperatures from 220 to 350 °C Type 2422/2425...

Type 2422 Valve, balanced by a diaphragm Type 2422 Valve, balanced by a diaphragm H1 Fig. 4: Dimension drawing of Type 2422 Valve balanced by a diaphragm with Type 2425 Actuator Table 5:  Dimensions in mm and weights · Type 2422 Valve balanced by a diaphragm Type 2422/2425 · Balanced by a diaphragm Nominal size Set points 0.05 to 0.25 bar 0.1 to 0.6 bar 0.2 to 1 bar 0.5 to 1.5 bar 1 to 2.5 bar Weight 2), approx. 1) 2) Valve with actuator Height H Actuator Height H Optionally with 640 cm² actuator The weight applies to the version with the material sp

Installation –– Install valves (balanced by a bellows or diaphragm) with the actuator suspended downward. –– Install pipelines horizontally with a slight downward slope on both sides of the valve to prevent condensed water from collecting. –– The direction of flow must match the direction indicated by the arrow on the body. –– Connect a control line to the actuator from the point of pressure tapping located approx. 1 m upstream of the valve in the pipe wall or at the point of measurement of the connected plant (with compensation chamber, if applicable). Accessories –– Screw joints with restriction...