- Home
- Companies
- Bray International, Inc.
- Products
- Bray - Model Series 20/21 - Resilient ...
Bray - Model Series 20/21 -Resilient Seated Butterfly Valve
The Series 20/21 resilient seated butterfly valve surpasses the high standards required in sanitary valve applications, and inherent flow characteristics and capabilities. Bray`s Series 20 valve is a wafer version with flange locating holes, and the Series 21 is the companion lug version for dead-end service and other flange requirements. Sanitary & Chemical applications. One-piece disc/stem. High Cv, low pressure drop.
- A - STEM BUSHING: Non-corrosive, heavy duty acetal bushing absorbs actuator side thrust.
- B - STEM SEAL: Double "U" cup seal design is self-adjusting and gives positive sealing in both directions and prevents external substances from entering the stem bore.
- C - DISC / STEM: One-piece design. The disc edge is spherically machined and hand polished to produce a bubble-tight shutoff, minimum torque, and longer seat life. The disc/stem design inherently provides complete protection from particle entrapment and bacterial decay, protection that is required for sanitary performance. For superior erosion and abrasion resistance, the one-piece disc/stem is fully encased in either EPDM or BUNA-N. The thin disc profile provides a much higher Cv (up to 50% greater than most through-stem designs) and greater pressure recovery, thus resulting in lower pressure drops and a more energy-efficient valve.
- D - 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 stem hole.
- E - 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.
- F - BODY: Two-piece wafer or lug style allows for ease of assembly and maintenance. Nylon 11 coating for excellent corrosion resistance is standard for 1"-8" valves and available on larger sizes upon request. Polyester coating is standard for 10"-20" bodies.
Bray`s Series 20 valve is a wafer version with flange locating holes, and the Series 21 is the companion lug version for deadend service and other flange requirements. All Bray valves are tested to 110% of full pressure rating before shipment.
A major design advantage of the Bray product line is international compatibility. The same valve is compatible with most world flange standards -ANSI Class 125/150. BS lOTables D and E.BS 4504 NP10/16. DIN ND 10/16. AS 2129 and JIS 10. In addition the valves are designed to comply with ISO 5752 face to face and ISO 5211 actuator mounting flanges. Therefore, one valve design can be used in many different world markets.
Bray interchangeability and compatibility offers you the best in uniformity of products and low-cost performance in the industry today.
Due to the modular concept of design, all Bray handles, manual gear operators, and pneumatic or electric actuators mount directly to Bray valves. No brackets or adapters are required.
For severe corrosive applications the one-piece disc/stem and seat are offered in PTFE with a standard Nylon 11 coated body. The basic seat design is PTFE bonded to EPDM and incorporates a unique primary/secondary sealing design. This PTFE valve provides excellent internal and external corrosion protection. Refer to Bray Technical Bulletin and brochure on PTFE, Nylon 11, and elastomer-covered Series 20/21 for further details and design features.
NYLON 11 COATING CORROSION PROTECTION
Bray`s standard product offers valve bodies l "-8" (25mm-200mm> with a Nylon 11 coating, providing excellent corrosion and wear resistance to the valve`s surface - the weakest part of most metal components. Nylon ll is a thermoplastic produced from a vegetable base rather than a petroleum base. Nylon 11 advantages include:
- Excellent Corrosion Resistance -Resists a broad range of chemical environ¬ments such as salt solutions, salt water, marine atmospheres, oils, greases and petroleum products. Salt spray tested in excess of 2,000 hours and seawater immersion tested for over 10 years without corrosion to metal substrates.
- Abrasion Resistance - very low co¬efficient of friction, resulting in longer service life and increased performance.
- Sanitary Applications - inert to fungus growth and molds, highly stain resistant. USDA Approved, as well as certified to ANSI/NSF6I for water service.
- Outdoor Weathering - resistant to ultra-violet radiation.
- Impact Resistant - tests have been performed without any peeling of coating.
- Electrical properties - excellent dielectric properties.
- Temperature Range -
Max: continuous service +200°F (93°C) intermittent service up to +250°F (12I°C) Min:-20°F(-29°C)
- Size Range:1" - 20" (25mm - 500mm)
- Body Style:Wafer, Lug
- Temperature Range:-20°F to 400°F (-29°C to 204°C)
- Pressure Ratings:Bidirectional Bubble-tight Shutoff: 150 psi (10.3 Bar)
- Body (CWP): 150 psi (10.3 Bar)
- Body Materials:Cast Iron, Ductile Iron, Stainless Steel, Aluminum
- Disc/Stem Materials:Stainless Steel, EPDM Molded over SS, BUNA-N Molded over SS
- Seat Materials:BUNA-N, EPDM, PTFE Lined EPDM, FKM* Polyurethane
- Applications:Sanitary Service, Mildly Corrosive, Toxic Media