Spence Engineering Company of Walden, New York, was founded in 1926 by Paulsen Spence, who patented the normally closed, external pilot-operated packless pressure regulator. A Spence pressure regulating valve takes steam at main pressure and holds a lower, steady pressure downstream, in building heating systems, institutions and industrial plants.
The Spence Type E main pressure regulating valve is on BoilerSupplies.com as a complete unit and as the valve only. BoilerSupplies.com also lists the Spence D series pressure reducing pilot, the Spence Type D-50 direct-operated pressure regulating valve, and Spence bends and fittings. The Type E with a D series pilot is the pilot-operated pair: the pilot senses downstream pressure and positions the main valve, which suits larger loads and a wide flow range. The Type D-50 senses pressure on its own diaphragm and suits smaller loads. The bends and fittings are the pipe pieces that run from the pilot to the main valve. Pick by the load first, pilot-operated for the large one and direct-operated for the small one, then match the pipe size.
Key facts
Spence Engineering Company was founded in 1926 by Paulsen Spence in Walden, New York.
Paulsen Spence held the original patent for the normally closed, external pilot-operated packless pressure regulator.
BoilerSupplies.com lists the Spence Type E main pressure regulating valve as a complete unit and as the valve only.
BoilerSupplies.com lists the Spence D series pressure reducing pilot, the Type D-50 direct-operated pressure regulating valve, and Spence bends and fittings.
A Type E main valve with a D series pilot is pilot-operated; the Type D-50 is direct-operated and senses pressure on its own diaphragm.
In-stock small-pack orders placed before 2:00 PM EST, Monday through Friday, ship the same day.
All of those: pressure reducing valve, PRV, steam pressure regulator and reducing valve are names for the same Spence valve on BoilerSupplies.com. A pressure reducing station is that valve piped in with its strainer, bypass and gauges. The Type E main valve with its D series pilot is the pilot-operated type. The Type D-50 is the direct-operated type, also called a direct-acting regulator. Order by the type on the tag.
Send the two tags, one from the main valve and one from the pilot. They carry the type (Type E, D series or Type D-50), the pipe size and the downstream pressure the valve is set to hold. Add the steam pressure on the inlet side and what the line feeds. Say whether you need the complete unit, the main valve only, the pilot only, or the bends and fittings.
Either way: BoilerSupplies.com lists the Spence Type E as a complete unit, main valve with pilot, and as the valve only, with the D series pilot on its own listing. A new installation usually takes the complete unit. A plant replacing a pilot that no longer holds pressure on a sound main valve orders the pilot alone, and new bends and fittings if the old ones are scaled or clogged.
A large load with a wide swing in flow: the pilot-operated pair, the Type E main valve under a D series pilot, handles that. The small pilot does the sensing and the big valve does the work. The Type D-50 senses on its own diaphragm and is the choice for a small load. Match the pipe size either way.
On a pilot-operated Spence valve, start at the pilot. A pilot with a failed diaphragm or dirt under its seat cannot position the main valve. A main valve with a cut seat passes steam when it should be shut. Scale in the bends and fittings between pilot and main valve chokes the line the pair depends on. Check the pilot, then the main valve, then the piping between.
Take a picture of both tags, main valve and pilot, and send them with the quantity through BoilerSupplies.com. By phone, Boiler USA is at 1-770-957-9599, toll free 1-800-780-3776.
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