TYPICAL SPECIFICATION

for

TYPE ED PRESSURE REGULATORS

Furnish & install, as shown on plans, steam pressure reducing valve of the self-operated, external pilot type, single seated, normally closed, dead end, multi-ply stainless steel diaphragm actuated, Spence Type ED pressure regulator or approved equal. This valve shall regulate an accurate delivery pressure within one (1 PSIG) pound per square inch plus or minus throughout the range of pressure and flow conditions scheduled regardless of deviation of the inlet pressure. They shall function quietly and shut tight on a dead end (no flow) shut off. Main valve to meet ANSI Class VI for maximum allowable seat leakage in accordance with standard, ANSI/FCI 70-2-1991. Regulators shall respond quickly and accurately without pressure deviation when installed on a two stage or three stage reduction.

Main valve bodies 2" and smaller to have screwed ends, 2-1/2" and larger shall be flanged ends. Body material to be cast iron or steel as required by service conditions. Seats and discs to be guaranteed by the manufacturer against the wire drawing action of the steam. Stems to be stainless steel.

Main valve spring to be installed in the general area of the diaphragm and pressure plate to minimize stem guiding surface and to keep the spring out of the path of the steam. Stuffing boxes will not be permitted. All parts Must be accessible without removal of valve from the line.

The spring loaded pressure pilot (Type D Series), shall be separate from the main valve and not integral with it. The pilot valve shall be connected via a nipple and union to the main valve body. A strainer screen shall be built into the pilot inlet. Pilots shall be designed to be interchangeable with all sizes of main valves. Bleedports and other orifice fittings shall be externally connected to facilitate troubleshooting and cleaning. Internal bleedports will NOT be acceptable.

Base bypasses or internal pressure relieving ports, when used, are to be located away from the jetting action of the flow through the seat and disc.

The regulator seat and disc (valve Cv) shall be designed not to pass more than twenty percent (20%) in excess of the required capacity. The safety relief valve to be sized to pass 100% of the maximum or end point capacity.

Install inlet gate valve, steam strainer, Spence PRV, outlet gate valve, globe valve bypass and figure 41 safety relief valve with all appurtenances as shown on drawings.

Furnish & Install at the discharge of each steam pressure reducing valve, when required, a muffling orifice plate and a noise suppressor as manufactured by Spence Engineering Co.,Inc. Muffling Plate shall be separate from noise suppressor and not integral with it. Inlet sizes to be as shown on drawings. The noise suppressor body size shall be same size as the downstream expanded pipe size. Noise suppressor shall be deceptive-reactive type, straight through design with no diverting baffles on its interior. All internal acoustical packing shall be of corrosion resistant material. Unit shall be capable of reducing sound pressure level emanating from the downstream piping up to 20 dBA. The muffling orifice plate to consist of a steel plate with primary orifices to which is welded a stainless steel screen with secondary orifices. The muffling plate shall be manufactured and installed separately. Muffling Plate to be capable of reducing pressure reducing valve noise levels by 6 to 10 dBA. The sound pressure level for each Reducing valve shall not exceed dBA.

Instal on each reducing valve, a removable, replaceable thermal insulating jacket Spence Lead Lined Insulcap or approved equal. Thermal jacket to be chemical resistant, silicone coated fiberglass. Insulation material to be 11 pound density fiberglass mat.. Thread and seam closure to be KEVLAR. Jacket to be capable of up to 14 dBA sound pressure level reduction with optional lead lining.