Butterfly Face-to-Face — Companion Article
Open the tool: https://pipingdesigners.com/tools-training/butterfly-face-to-face/
What this tool does
Butterfly Face-to-Face looks up the length of wafer and lug butterfly valves from NPS 2 to NPS 20.
When to use it
Use it for layout space and for working out stud lengths through a wafer or lug valve.
Inputs
- Body: wafer or lug.
- Size.
- Units: inches or millimetres.
How it works
The page reads one manufacturer’s weights and dimensions drawing (Bray series 30/31). Millimetres are those printed on the drawing.
Understanding the result
The length shows as a card, marked single source.
Engineering considerations
- The disc swings past the faces when open. Check clearance to the next fitting or a lined pipe.
- Lengths vary by maker. Use the vendor’s drawing for the valve you buy.
Example
NPS 2: face-to-face 1.62 in, 41.2 mm.
Standards/references (licensed vs interim)
Licence status is interim. The numbers come from a single manufacturer drawing, not from licensed the applicable valve standard (for example API 609) text. The page builds its source note from the dataset and names the standard to verify against. Always check the current edition of the applicable valve standard (for example API 609), or the manufacturer’s certified drawing, before you use a figure on a deliverable.
Limitations/disclaimer
- Single source.
- No control valves.
- The result is preliminary and needs engineering review.
Use the tool
Calculate now: Butterfly Face-to-Face
Related tools
- Valve Face-to-Face (new tool, being added to the site).
- Stud Bolt Length (new tool, being added to the site).