Watts BF-03-121-25-M2 4 Butterfly Valve, Ductile Iron, Lug

The Watts BF-03-121-25-M2 is a 4" full-lug butterfly valve with an aluminum bronze disc, operated by a 10-position lever. It features a ductile iron body and a buna-n seat. Rated to 200 psi and 14°F to 176°F.

This 4" full lug style butterfly valve, model BF-03-121-25-M2, is used in HVAC, irrigation, OEM, commercial, and institutional applications and wherever positive shutoff is required to control the flow of liquids, gases, and slurries. It features iron body construction, aluminum bronze disc, Buna-N seat, a stainless steel shaft, mounting pad for 10-position lever.

Features

• Cast iron body
• Aluminum bronze disc
• Buna-N seat
• Lever handle

Common Questions

Can I use this valve at the end of a line or for dead-end service?

Yes. This is a full-lug body, so it is rated for bidirectional dead-end service to the full pressure rating (200 psi). The threaded lugs let you unbolt and remove downstream piping while the valve holds pressure, so it can terminate a line or isolate equipment for service.

What temperature range does this valve handle?

14°F to 176°F. On a resilient-seated butterfly valve the temperature limit is set by the seat elastomer, and this valve uses a Buna-N seat. If you need a wider range, the same body is offered with other seat compounds: Buna-N (14°F to 176°F), EPDM (5°F to 248°F), or Viton (-4°F to 302°F).

Can I mount an actuator on this valve?

Yes. The valve has an integral ISO 5211 mounting pad, so it accepts electric or pneumatic actuators without an adapter kit. This model ships with a 10-position lever, which can be removed and replaced with an actuator later.

Is this valve approved for potable water?

Yes. It is NSF/ANSI 61-G listed for potable-water service, and also meets MSS SP-67 and API 609 for face-to-face dimensions and construction.

Will this bolt up to my existing flanges?

Yes, on ANSI 125/150 flanges — this valve is dimensioned to API 609 and MSS SP-67 and mates to ANSI Class 125 and Class 150 flanges in 4" pipe. Use the correct lug/wafer bolting for your body style and check that the disc has room to swing clear of the mating pipe ID.

Can I throttle flow with this valve, or is it on/off only?

Both. The 10-position lever locks the disc at any of ten detents between full open and full closed, so it can throttle as well as provide positive shutoff. For fine or frequent throttling, or if the handle is hard to hold against flow, the gear-operated version of this model is the better choice.

Specifications

• Type: Butterfly
• Size: 4"
• Connection: Lug
• Body Material: Ductile Iron
• Seat / Seal Material: Buna-N
• Max Pressure (psi): 200
• Application: Irrigation
• Operation: Manual
• Country of Origin: China
• Warranty: 1 Year Limited
• MPN: BF-03-121-25-M2 4
• Temperature: 14°F to 176°F
• Certifications: NSF 61-G, MSS SP-67, API 609
• Disc Material: Aluminum Bronze
• Stem Material: 416 Stainless Steel
• Operator Type: 10-Position Lever
• Dead-End (End-of-Line) Service: Yes
• Flange Class: ANSI 125/150
• Actuator Mounting Pad: ISO 5211