A well designed steam system will produce clean dry steam in the boiler house ready for delivery at high pressure through the distribution network. This maximises the potential to generate and supply saturated steam of the best quality at the lowest overall cost.
The majority of applications however require a reduction in pressure at the point of use, the benefits of this include:
• A reduction in the capital cost of equipment.
• Operating plant costs will decrease by reducing flash steam.
• Saturated steam pressure is directly related to temperature. Controlling the pressure will therefore automatically control
the temperature avoiding the need for additional temperature control equipment.
• The flexibility to reduce to various lower pressures through the plant to suit each particular application.
However there are some applications that have a need to sense and control upstream of the valve to maintain or disperse excess pressure in the distribution pipeline in order to safeguard the equipment using it - this requires a pressure surplussing / maintaining valve.
Two main groups of pressure control valve are available for either pressure reduction or surplussing applications:
• Self-acting requiring no external power or input.
• Pneumatically actuated with either a pneumatic or electrical control system.
The final selection will depend on the requirements of the application and customer preferences.
Whatever the reason for reducing or maintaining pressure, proper control at any time demands an automatic valve that can reduce or maintain steam pressure accurately, reliably and economically.