GESTRA CW 41 & CW 41/4 PN 16 Cooling Water Control Valves | Gestramat®

GESTRA CW 41 & CW 41/4 PN 16 Cooling Water Control Valves | Gestramat®

The cooling-water control valves type CW are direct-acting proportional controllers for in- stallation in cooling water or brine return lines. They ensure that the cooling-water outlet temperature is maintained at a preset value, calculated for the process requirements.

When using cooling-water control valves, higher temperatures are possible than with an uncon- trolled process. As a result of the larger heat absorption by the cooling water or brine, cooling- agent and energy consumption are reduced.

In particular, in new plants where the installa- tion of cooling-water control valves has been planned right from the beginning, capital costs are reduced. Due to the reduced coolant flow- rate, pipework, valves and pumps can be smaller. Furthermore, the cooling-water con- trol valves type CW ensure an optimum distri- bution of the coolant to all heat exchangers which are installed in parallel.

The regulator of the CW 41 consists of one, two or three thermostats (3) (depending on the valve size) mounted in series within a double-seat valve cone (2). The upper cone closes tight whilst the lower one is designed with a tolerance to form a leak passage (“s” cone), or the leak passage is formed by a borehole in the cone (“r” cone).

The thermostats (3) contain an elastomer ther- mal expansion material (“n” and “k” thermostats) or wax (“w” thermostat). Under the influence of heat the volume of the thermostats increases, projecting a pin which is included in the ther- mostat body.

The lift of the thermostats is transmitted to the valve cone via the pin of setting device (6), supporting the thermostats. With rising cooling- water outlet temperature, the valve cone is moved in the opening direction against the force of the spring. When the temperature drops again the valve cone is moved by the spring (7.1) in the closing direction.

The position of the setting pin can be modified with the aid of adjusting key (11) to obtain higher or lower cooling-water outlet temperatures (see overleaf).

The continuous bleed flow guarantees a sensi- tive response even when the valve is closed. The bleed flow can be increased by screwing in setting screw (7.6).