Central Station Steam Company offers two versions of regulators, Pressure Operated (CS50 & CS 60 Series) and Temperature Operated (CS80 & CS89 Series). Depending on the application and desired result either may be applied. With either type of regulator Central Station Steam Company offers "Sliding Gate Trim" because this unique seat design offers simplicity in design, unsurpassed trim life and very good accuracy.

The trim consists of a stationary slotted disc (seat) and a moving slotted disc (plug), which allows us to control the trim orifice to control the flow rate of liquids, gases and steam. Both discs feature a special ceramic based coating for low friction and, because the seats are pre-lapped at the factory and are self-lapping during operation, there is outstanding wear resistance.

The regulator design features a straight through flow path and the direction of the disc travel is perpendicular to the flow, not opposed to the direction of the flow. This regulator design therefore does not rely on an unbalanced trim design, which allows us to provide a wide range of control with very little hysteresis. Since the flow path is straight, this trim design minimizes turbulence and is therefore generally less noisy that conventional regulator designs. Since the plug is always in contact with the seat, trim chatter is totally eliminated.

Pressure Operated (Reducing CS60 or Back Pressure CS50 Series):
The pressure chamber of the regulator features a diaphragm opposed by a pre-tensioned spring. The regulated pressure is sensed beneath the diaphragm and, if it exceeds or is below the regulator set point established by the spring tension, it will move the trim to re-establish balance. Standard diaphragm material is "Jorlon", which is extremely durable and virtually universally applicable up to 450 degrees F. Stainless Steel diaphragms are available for process temperatures up to 650 degrees F. These diaphragms have been tested, without failure, to over 1,000,000 full stroke cycles and are ideal for steam, gases and liquids.

Temperature Operated (CS80 and CS89 Series):
The temperature regulator features a liquid operated diaphragm. A pre-measured amount of liquid fill is drawn into the thermal system filling the upper diaphragm chamber, the capillary tube and most of the bulb. As the controlled temperature increases, the volatile liquid fill in the sensing bulb begins to vaporize and creates pressure on the sealed system. This pressure drives the valve stem closed, which has a very short travel stroke, in turn closing direct acting valves, or opening reverse acting valves.

In order to select/recommend the correct regulator for the application, we need to understand what the requirements are so that we can size the regulator properly. We would need the following information:

1. 1. Piping: Inlet & outlet size, pipe schedule, material and process connection requirement.
2. 2. Flow Rate: Maximum, normal and minimum flow rates & flow rate engineering units.
3. 3. Temperature: Temperatures at the various flow rates.
4. 4. Pressures: Inlet and regulated pressure. In case of a back pressure regulator, we would need to know the desired regulated back pressure.
5. 5. Medium: Type of fluid to be regulated. If not a standard fluid, we would need:
   • Density, viscosity, vapor pressure & critical pressure for liquids.
   • For gases, we would need density, viscosity and compressibility factor.
   • For steam, we would need to know whether we are dealing with saturated or superheated steam.