Sieve Tray Weeping & Minimum Vapor Velocity Calculator
Determine sieve tray weeping limit, minimum hole vapor velocity (m/s), vapor F-factor, and clear liquid head to prevent tray liquid dumping per Kister.
Tray Geometry & Fluid Densities
Weep Limit & Operating Margins
Recommended Tools & Equipment
Tested hardware and components for high reliability
Frequently Asked Questions
What is tray weeping vs tray dumping in a distillation column?
Weeping occurs when upward vapor velocity is insufficient to support the liquid head on the tray deck, allowing liquid droplets to leak through the perforated holes. Dumping is catastrophic weeping where all liquid bypasses downcomers, collapsing tray separation efficiency to near zero.
What is the minimum recommended dry tray pressure drop to prevent weeping?
As an industrial rule of thumb (Fair & Kister), dry tray pressure drop (hd) should be at least 15% to 20% of the total liquid head (hw + how) on the tray to maintain an even vapor distribution.
How does hole diameter affect turn-down ratio?
Smaller holes (e.g., 3 mm to 6 mm) provide higher surface tension stability and lower weep velocities than 12.7 mm holes, allowing wider turn-down flexibility (operating down to 40%–50% of design rates).