The Bray Series 30 Wafer and Series 31 Lug style resilient seated butterfly valves feature a one-piece body with a high-strength through stem design utilizing an internal disc to stem connection.
The Series 30/31 is engineered to provide bidirectional bubble-tight shutoff and isolation of the line media from the stem or valve body.
Available with a wide selection of high-quality resilient seat & disc materials for a variety of applications, our Series 30/31 butterfly valves are easily automated for on-off or modulating service.
Resilient Seated Butterfly Valve
Series 30/31
Size Range
NPS 2 to 20 / DN 50 to 500
NPS 14 to 20 / DN 350 to 500
NPS 14 to 20 / DN 350 to 500
Temperature Range
-20°F to 400°F (-29°C to 204°C)
Maximum Allowable Operating Pressure
175 psi (12 Bar)
150 psi (10 Bar)
150 psi (10 Bar)
Specifications
Resilient Seated Butterfly Valve - Series 30/31
Size Range
NPS 2 to 20 / DN 50 to 500
NPS 14 to 20 / DN 350 to 500
NPS 14 to 20 / DN 350 to 500
Body Materials
Cast Iron, Ductile Iron, Carbon Steel, Aluminum
Temperature Range
-20°F to 400°F (-29°C to 204°C)
Stem Materials
Stainless Steel, Monel K500
Maximum Allowable Operating Pressure
175 psi (12 Bar)
150 psi (10 Bar)
150 psi (10 Bar)
Seat Materials
BUNA-N, EPDM, FKM, Polyurethane
Shutoff Rating
Bidirectional Bubble-tight
Disc Materials
Nylon 11 Coated Ductile Iron, Aluminum Bronze, Stainless Steel, Hastelloy®, Halar® Coated Ductile Iron
Body Style
Wafer, Lug
Design Standard
MSS SP-67, API 609, Category A
Flange Drilling
ASME B16.1 Class 125, ASME B16.5 Class 150, EN 1092 PN 10, 16
Testing Standard
MSS SP-61, API 598, EN 12266-1
Certifications
ABS, ATEX, Bureau Veritas, CRN, DNV, FDA 21 CFR 177.1550, NSF 61/372, PED, PE(S)R
Face to Face
MSS SP-67, API 609, Category A, EN 558
applications
Potable Water, Wastewater, Seawater, HVAC
Features & Benefits
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A. Stem Retaining Assembly
The stem is retained in the body by means of a unique Stainless Steel Spirolox® retaining ring, a thrust washer and two C-rings, manufactured from brass as standard, stainless steel upon request. The retaining ring may be easily removed with a standard hand tool. The stem retaining assembly prevents unintentional removal of the stem during field service.
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B. Stem Bushing
Non-corrosive, heavy duty acetal bushing absorbs actuator side thrust.
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C. Stem Seal
Double "U" cup seal design is self-adjusting and gives positive sealing in both directions.
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D. Neck
Extended neck length allows for 2" of piping insulation and is easily accessible for mounting actuators.
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E. Disc
Casting is spherically machined and hand polished to provide a bubble-tight shutoff, minimum torque, and longer seat life.
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F. Body
One-piece wafer or lug style. Polyester coating for excellent corrosion resistance. Nylon 11 coating is available as an option.
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G. Primary & Secondary Seals
These seals prevent line media from coming in contact with the stem or body. Primary Seal is achieved by an interference fit of the molded seat flat with the disc hub. Secondary Seal is created because the stem diameter is greater than the diameter of the seat stem hole.
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H. Stem
Precision double "D" disc to stem connection drives the disc without the need for screws or pins. The close tolerance, double "D" connection that drives the valve disc is an exclusive feature of the Bray valve. Disassembly of the Bray stem is just a matter of pulling the stem out of the disc.
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I. Seat
Bray's tongue and groove seat design lowers torque and provides complete isolation of flowing media from the body. The seat also features a molded O-ring which eliminates the use of flange gaskets.