Products
HD Regulator - Pilots

HD Regulator- Pilots

The HD Main Valve is used in conjunction with a pressure or temperature pilot to control the volume of steam flow thru the valve for the purposes of maintaining accurate downstream pressure or precise temperature of a process.

PP- Pressure Pilot - spring loaded

The PP pressure pilot is used when its required to reduce pressure in steam systems. Three spring ranges are available for controlling downstream steam pressure from 30-200 psig. The adjustment screw is located on the top of the pilot valve and used for setting downstream pressures. The model PP5 is available when increased accuracy is required in low pressure applications (3-25 psig).

PT-Temperature Pilot

When the temperature of the liquid filled sensing bulb falls below the desired set temperature steam will flow thru the main valve, when the set temperature is reached the main valve closes. The set temperature is easily adjusted throughout its range. Temperature pilots with 8 ft. and 15 ft. capillary length and various sensing bulb types are available depending upon system requirements. The PTRP is an alternate temperature pilot style that uses a fast responding Liquid-Vapor for application requiring quicker response time such as steam-to-water heaters.

PA-Pressure Pilot - air loaded

The Air-loaded Pressure Pilot can be used when frequent, quicker or easier adjustability of steam pressure is desired or when main valve is located remotely from where pressure adjustment takes place. Steam pressure control is done thru adjustment of a small air regulator that controls air pressure to the top of the pilot.

PS-Solenoid Pilot

The PS Solenoid Pilot allows for the HD Main Valve to be enabled using an electrical switch to activate a small solenoid valve allowing steam to flow to the pilot valve. The PS Pilot can be used for system automation or as a shut down device. A solenoid Pilot is generally used in conjunction with a Pressure or Temperature control pilot to enable or to disable valve operation.

HD Regulator - Pilots Selection

The HD Series Pilot-Operated Regulating Valve was designed for control of temperature and pressure in steam service applications. Several different control pilots can be mounted to the valve to control pressure, temperature, or a combination of both. When two or more pilots are used together (both a pressure and a temperature pilot) an additional pilot adapter for the second pilot is required (must indicate when ordering). The most common pilots are the PP-Pilot for pressure reducing, and the PT-Pilot for temperature control. The Main Valve and Pilot are purchased separately.

 

PRODUCT MODELS APPLICATION RANGE
PRESSURE
Spring-loaded pressure pilots for general service steam pressure reducing.

Inlet: 300 PSIG

Outlet: 3-200 PSIG

Air-loaded Pressure Pilot can be used instead of spring-loaded PP pilots for pressure regulation in remote installations. Also used in conjunction with PTR & PTL temperature controllers. Inlet: 300 PSIG

Outlet: 3-200 PSIG
TEMPERATURE CONTROL General purpose liquid-filled temperature pilot used when heating liquids to a desired temperature.

Inlet: 15-300 PSIG

Temperature Control: 60-300ºF

Special purpose vapor tension temperature pilot for increased sensitivity and reduced reaction time.

Inlet: 15-300 PSIG

Temperature Control: 60-300ºF

BACK PRESSURE For controlling upstream pressure of the HD Regulator. Inlet: 300 PSIG

Outlet: 3-200 PSIG

DIFFERENTIAL PRESSURE Differential Pressure Pilot with two separate sensing ports for maintaining differential pressure between steam and an alternate medium.

Inlet: 300 PSIG

Outlet: 3-200 PSIG

ON / OFF Solenoid Pilot can be used in conjunction with any of the listed pilots for electrical on/off control of HD Regulator

Inlet: 250 PSIG

Pressure Range:
PS1: 0-180 PSIG
PS2: 180-250 PSIG

How HD Regulator Pilots Work

The HD Series Pilot-Operated Regulating Valve was designed for control of temperature and pressure in steam service applications. The HD Series is made of ductile iron for extended pressure and temperature ratings. Several different control pilots can be mounted to the valve to control pressure, temperature, or a combination of both. When two or more pilots are used together (both a pressure and a temperature pilot) an additional pilot adapter for the second pilot is required (must indicate when ordering). The most common pilots are the PP-Pilot for pressure reducing, and the PT-Pilot for temperature control. The Standard Main Valve is used for an inlet steam pressure range of 15-300 PSI. The Low-Pressure Main Valve contains a lighter main valve spring and is available for an inlet pressure range of 5-20 PSI. The Main Valve and Pilot are purchased separately.

Controlling Pressure

The HD Pilots control the operation of the HD Main Valve. When reducing downstream pressure, the sensing line connects the PP-Pressure Pilot to the downstream side of the regulator. Pressure in the sensing line applies an upward force to the pilot diaphragm to compress the adjustment spring, closing the pilot and main valve.

Pilot Operation

When system pressure equals the set point, the diaphragm moves upwards against the force of the adjusting spring, closing pilot valve. When the pilot valve is shut, steam cannot pass thru to the underside of the regulator diaphragm, closing the regulator. When the steam pressure falls below its set point, the pilot valve opens allowing steam to lift the main valve diaphragm which opens up the regulating valve.

Combination Pilots

The HD-Series Steam regulating valve can be used with up to three pilots simultaneously to control the operation of the valve. An example is when steam is used to heat water in a Heat Exchanger. The Temperature Pilot will maintain precise control of outlet water temperature by controlling the amount of steam flow through the valve while a Pressure Pilot limits the maximum outlet steam pressure of the regulator to the Heat exchanger. A third Solenoid pilot can be added to electrically activate or de-activate the system.

A Pressure Pilot is used with the HD Regulator to control steam pressure in steam mains or for process equipment. The PP-Pressure Pilot (1.0 PSIG accuracy) is adequate for controlling pressure in most industrial applications. For increased accuracy use PP-5 Pilot. (0.5 PSIG accuracy)

The PT-Temperature Pilot is used with the HD regulator to control temperature in various processes and systems.
Some examples are:
• Oil heaters • Storage Tanks
• Process heaters • Vats
• Dryers • Jacketed Kettles

The Temperature Pilot is used with the HD Regulator to control temperature in various processes and systems. Some examples are: Oil heaters, Ovens, Process Heaters, Vats, Dryers and Jacketed Kettles. The “PTRP” will control lower temperatures than the standard Temperature Pilot.

The HD Regulator with the Air Pilot is used for reducing steam pressure on steam mains and process equipment. The “PA” Air Pilot can also be used in conjunction with the PTL and PTR Pneumatic Temperature Controllers for controlling temperature in process applications. The principal advantage of the “PA” Air Pilot over standard spring-loaded pilots is that pressure adjustments to the regulator can be made from a remote location. A regulator placed in a difficult to reach or inaccessible location can be adjusted by a remote control panel board placed in an accessible location.

The Back-Pressure Pilot used with the HD regulator, maintains upstream pressure in steam systems. These regulators are commonly used to supply flash steam to low pressure mains.

The EP Series are used with HD regulators for a variety of applications including On/Off Control. The control signal range is 4-20 mA or 0-10V. A Low-Pressure version (-LP) is available for 5-20 PSIG steam supply pressures.

The TSP Series are used to prevent over-pressurization of downstream steam piping systems. The TSP is typically installed on an HD regulator downstream of the main Pressure Reducing HD. Typical applications are when piping code allows for an alternative to a safety valve discharging to atmosphere.

The “PS” Solenoid Pilot can be used in conjunction with All Pilots to electrically control on/off operation of the HD Regulator. When the solenoid pilot is used, the regulator can be turned on or off by electrically activating or de-activating the solenoid.