Neles BW series metal seated high performance butterfly valve with one piece body design, for both control and tight shut- off applications. Multiple body options makes it particularly well suited for the refining, power, petrochemical and chemical industries. The BW provides extended operational life in control, tight shut-off and critical applications such as high cycle, high temperature, cryogenic, oxygen and abrasive applications, etc. Rating from ASME 900 to 2500 makes the BW a sound control or shut-off valve in severe service applications. 
Excellent on-off capabilities
- Uniquely functioning full metal seat design assures tightness over long time periods.
- Contact between disc and seat is mechanically induced and does not rely on assistance from differential pressure.
- Long term tightness is maintained even in high cycle rate services. Tightness in not compromised by large thermal cycling either.
- Low friction and excellent wear resistance.
- Lowered operational torque reduces actuator size
- Heavy-duty stem and ingenious bearings design extends service life and is insensitive to thermal cycles and impurities.
Excellent flow control capabilities
- Good controllability via smoothly rising installed characteristic curve at both very small openings and nearly full Cv positions. Series BW provides very wide rangeability in fairly low pressure drop services.
- Good dynamic stability in both flow directions. □ Available with a variety of actuators, positioners and accessories for single source responsibility. Mounting face according to ISO 5211.
Abrasion resistant construction
Solid, sturdy all metal seat design is based on metal-tometal contact. No resilient parts are needed for
Low emissions
- The live loaded gland packing is located right after the outer bearing maximizing the tightness. The emissions are well below the international standards.
- Furthermore, there are no resilient parts exposed to the medium.
Extremely wide pressure and temperature range
- Differential pressure/temperature ratings in accordance with ASME B16.34.
- Extremely wide temperature range up to +1150°C / +2100 °F.
Low cost of ownership
- Extremely high cycle life minimizes the need for maintenance and increases the Mean Time Between Failure (MTBF) value.
- Interchangeable seats can be replaced without disassembling the disc and shaft. Seat replacement does not require any adjustment or special tools.
Certified emission and fire-safe performance
- Emission certified according to industry standard, ISO 15848-1 class B in shut-off applications.
- Fire safe certification according to API 607, 6th edition
Certified safety performance
- SIL certification to meet IEC61508 requirements
- Capable to SIL 3 level