SAMSON Type 3222 HVAC Globe Valve DN 15-50 PN 25

SAMSON Type 3222 single-seated globe valve for HVAC and heating

The SAMSON Type 3222 is a compact single-seated globe valve for heating, ventilation and air-conditioning systems. It comes in sizes DN 15 to 50 (G ½ to 1 for the threaded version) at PN 25, and it is built in two temperature versions: up to 150 °C for water, oil and other liquids, and up to 200 °C for water above 150 °C and steam. Seven Star LLC supplies the Type 3222 in Oman and the GCC as an independent supplier based in Muscat.

The datasheet covers the valve together with a family of actuators, written as pairs such as 3222/5857, 3222/5827 or 3222/2780. The part before the slash is the valve, and the part after it names the actuator. This lets the same bronze or ductile-iron body work in a domestic hot-water set, a chilled and hot water network or a small process heating loop.

Some versions use a balanced valve plug, which lowers the force the actuator must provide. The valve and actuator are joined by a force-locking connection, so fitting the actuator needs no special setting.

How to read the Type 3222 combinations

• 3222/5857 and 3222/5827: electric actuators with three-step control or a positioner (0/4 to 20 mA or 0/2 to 10 V). The 5827 version is also offered with fail-safe action.
• 3222/5757-3, 5724-3 and 5725-3: actuators with a process controller for domestic hot water heating (the 5725 can fail safe).
• 3222/5757-7, 5724-8 and 5725-8: actuators with a process controller for heating and cooling, with the 5724-8 and 5725-8 holding two PID control modules.
• 3222/2780-1 and 2780-2: pneumatic actuators with a control signal of 0.4 to 1 bar (2780-1) or 0.4 to 2 bar (2780-2); the 2780-2 can take an integrated positioner.

The datasheet notes that the valves with TROVIS 5725-3, 5725-8 and Type 5827-A actuators for the stem-extends fail-safe action are tested by TUV to DIN EN 14597, and the register number is available on request. Type 3222 N is a separate valve for district heat supply described in its own datasheet.

Type 3222 technical specifications

KVS coefficients and sizes of the Type 3222

Reduced KVS values let the designer match the valve to a small heat load, which improves control on low flows. The metal seat serves KVS up to 2.5 and the soft-sealed plug serves KVS 3.6 and above.

Principle of operation of the Type 3222

The medium passes through the single-seated valve in the direction of the arrow on the body. The position of the plug relative to the seat sets the free area, so each plug position corresponds to a flow. A spring in the valve opens it when the actuator stem retracts, and the actuator pushes the plug down to throttle or close.

A special version is required for water above 150 °C and for steam, and for those service conditions the valve must be installed upright. For water, oil and other liquids it can be mounted in any position as long as the actuator does not hang downward. If the line is insulated, do not insulate the actuator and the coupling nut, and use the intermediate insulating piece, which itself should not be insulated over its 25 mm length.

Fail-safe behavior with the Type 3222

Where the valve is fitted with a fail-safe actuator, two actions are possible when power or air is lost. With the stem extending (FA) the valve closes, and with the stem retracting (FE) it opens. The datasheet table lists which actuator types give each action: the 5827-A and 5725 actuators give stem-extends action, 5827-E gives stem-retracts, and the pneumatic 2780-1 and 2780-2 can be ordered in either direction.

For a hot water heating loop fail-closed is the usual choice, whereas for a chilled-water coil protection against freezing may call for fail-open. Decide this early because the actuator model depends on it.

Selecting a Type 3222: checklist

• Medium and temperature: liquid up to 150 °C, or water above 150 °C and steam up to 200 °C.
• Nominal size, KVS and the seat type; compare the allowable differential pressure with the system pressure drop.
• End connection: welding ends, threaded ends, flanges, female thread or flanged body.
• Seal material: EPDM, or FKM for oil service.
• Actuator: three-step electric, positioner type, process controller for domestic hot water, or pneumatic 2780.
• Fail-safe action and supply voltage or air pressure.
• Intermediate insulating piece 1990-1712 where required, and extra electrical accessories.

Installation and maintenance of the Type 3222

Flush the pipework first, since small particles lodge between the plug and seat and cause leakage. Install the valve with the flow arrow matching the flow and keep to the mounting position rules above. The force-locking coupling lets the actuator be taken off or replaced without disturbing the pipe, which keeps service short.

Inspect the valve periodically for external leakage and wear. The seat and plug are made of stainless steel so scale rarely causes damage, but dirty systems should have a strainer upstream. For steam duty always inspect the insulating piece and the actuator ambient temperature, which must stay within the actuator limits.

Typical Type 3222 applications in Oman and the GCC

The main use is in HVAC. District cooling plants, hospitals, hotels and office towers use chilled-water and hot-water control valves in large numbers, and the Type 3222 with an electric actuator fits terminal units, air handling unit coils and heat exchangers for domestic hot water. In industrial buildings and utilities it also controls small process heating and cooling loops and steam heaters.

Gulf ambient conditions favor valves with robust stainless internals and corrosion-resistant bodies, and the pneumatic 2780 version is useful where compressed air is available and electronics are best kept away from heat. Seven Star LLC can help you match the actuator to the controller already in your plant.

Information to send with an RFQ for the Type 3222

• Medium, temperature, pressure and flow, or the DN and KVS if known.
• End connection type and flange standard.
• Actuator version, control signal and supply (voltage or air).
• Fail-safe direction and any additional electrical accessories.
• Controller or process controller type for domestic hot water or heating-and-cooling duty.
• Quantity and delivery location.

Documents and quotation

A SAMSON datasheet (T 5866) is attached on this page with materials, KVS table, actuator combinations and dimensions.

Send the load, medium and actuator preference to Seven Star LLC and we will confirm the correct combination and prepare a quotation.