Brightwater Treatment Plant – Woodinville, WA (Aeration Basin Upgrade)
Success Story About IRIS Control ValveWe conducted an Iris Valve “Repeatability” test at King County’s – Brightwater Treatment Plant in Seattle, WA and recorded a > 99% Repeatability! This is real-world data, recorded in the field, and witnessed by Brown and Caldwell Engineers!
RESULT: Less than 1% Flow Variation
WHY? ANSWER: Precise Movements
Three (3) tests were run on Basin 2 – Zone 2 (8” Iris valve):
- Repeatability test at 90% Open
- 1st – Measured 1,800 SCFM at 90% Open
- 2nd – Closed valve to 30% for 1-minute
- 3rd – Opened valve back to 90%
– observed 1,791 SCFM (1,800 – 1,791 = 8 SCFM)
- Repeatability test at 75% Open
- 1st – Measured 1,588 SCFM at 75% Open
- 2nd – Closed valve to 30% for 1-minute
- 3rd – Opened valve back to 75%
– observed 1,575 SCFM (1,588 – 1,575 = 13 SCFM)
- Repeatability test at 55% Open
- 1st – Measured 1,190 SCFM at 55% Open
- 2nd – Closed valve to 30% for 1-minute
- 3rd – Opened valve back to 55%
– observed 1,173 SCFM (1,190 – 1,173 = 17 SCFM)
Egger’s patented Iris valve uses a robust “Spindle” control assembly:
- Spindle assembly rotates an external drive nut to precisely open and close the valve.
- Spindle actuation is mounted externally for easy maintenance.
- Spindle uses a rigid bearing support (other valves, this work is done by the actuator).
- Spindle mounted pointer provides exact valve position.
- Quality multi-turn actuator is hard-mounted to our flange.
- The Spindle on an 8” Iris valves travels 62 turns to Full Open & 62 turns back to Full Close or a length of 7.3 inches.
