We Offer Custom Design Service for Vacuum Requirements

Some batches cannot run in an open tank. Solvent flashes. Air stays trapped in the film. Moisture ruins a resin. A powder clouds the room the moment it hits the liquid. For those jobs, the mixer has to hold vacuum while it still wets, disperses, and circulates.

Kady International offers custom design service for vacuum requirements. The same high-speed rotor-stator mills used for coatings, inks, adhesives, rubber solutions, and high-solids slurries can be built as sealed systems. The head, shaft, vessel, and controls are engineered so the mill keeps working under reduced pressure instead of leaking air back into the batch.

Why Vacuum Belongs on a Dispersion Mill

A Kady Mill pumps material through slotted rotor openings and drives it into a closely fitted stator at tip speeds up to 9,000 feet per minute. That action breaks agglomerates, wets solids, and builds emulsions. Vacuum adds a second process tool:

• Deaeration. Trapped air is pulled out while the head keeps shearing, which helps coatings, adhesives, and sealants apply without pinholes or foam.
• Dust-free powder addition. Fumed silica, pigments, and other light powders can be drawn into the liquid under vacuum instead of floating on the surface.
• Lower boiling point. Solvent or water can be removed at a milder temperature, which protects heat-sensitive polymers.
• Less oxidation. Air is kept off the batch during long wet-out or cook steps.
• Tighter process control. A sealed vessel holds composition more steadily than an open tank with a strong vortex.

Kady lists aeration and deaeration among the jobs its mills already do. Vacuum design makes those jobs repeatable at plant scale.

What Custom Vacuum Design Includes

Vacuum is not a bolt-on lid. The mill has to stay sealed at the shaft, the head, the vessel joints, and the process connections. Kady engineers the package around the formula and the plant:

• Vacuum-rated vessels matched to the mill, or adaptation kits for an existing tank
• Shaft seals and enclosed-shaft options that limit air leak paths
• Top-entry or bottom-entry heads chosen by tank layout and whether solids settle
• Jacketed tanks for heating or cooling while the batch is under vacuum
• Pressure capability when the same vessel must also run above atmosphere
• Sight, sample, and feed ports that keep the seal when powder or liquid is added
• Materials of construction for solvents, abrasion, or sanitary service
• Variable-speed drives so tip speed can change as viscosity rises during solvent strip

Lab mills such as the LT2000 already offer enclosed shafts for deaerating work and optional vacuum service. That same approach scales to production mills and to continuous-flow units when the line needs a sealed, steady stream.

Applications That Need Vacuum Mixing

Custom vacuum design shows up wherever air, moisture, or solvent control decides product quality:

• Coatings and inks that must deaerate before application
• Adhesives and sealants that cannot tolerate bubbles in the bead or film
• Rubber and resin solutions that lose solvent too fast in an open tank
• High-solids slurries where vacuum helps wet powders and cut foam
• Cosmetic, food, and specialty chemical batches that need a clean, air-free finish
• Formulas that load fumed silica or other light powders without a dust cloud

Because the rotor-stator head still supplies high energy, many of these batches finish wet-out, dispersion, and deaeration in one vessel. That cuts the extra tank, vacuum kettle, and transfer step that plants often add after a conventional dissolver.

How the Process Runs

1. The sealed vessel is charged with liquid and, if needed, placed under vacuum.
2. Solids are added through a closed port or drawn in by the vacuum.
3. The Kady head circulates the batch and shears agglomerates at high tip speed.
4. Air and other gases migrate out while the mill keeps the liquid moving.
5. Temperature is held with a jacket if solvent strip or cook is part of the cycle.
6. The finished mix is discharged without opening the process to extra air if the spec requires it.

Auxiliary propellers above and below the head keep heavy or sticky material feeding the stator so vacuum does not leave a dead zone at the bottom of the tank.

From Lab Vacuum Trial to Plant Equipment

Kady designs each vacuum mill to the duty, then proves it when needed. Free testing can show how the formula behaves under vacuum: cycle time, temperature, foam, and final grind. Lab and production units share the same rotor-stator idea, which reduces scale-up risk.

Refurbished mills can also be custom-modified for vacuum service and shipped with a new-machine warranty. That path helps when a plant needs a sealed mixer without waiting on a full new build.

To start a vacuum design, share the product, the target vacuum level, batch size, solvent or water system, and whether the mill must also heat, cool, or run under pressure. Kady will recommend the head, vessel, seals, and controls.

Kady International
30 Parkway Drive
Scarborough, ME 04074
Phone: 207.883.4141
Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
Hours: Monday–Friday, 8 AM–5 PM

We offer custom design service for vacuum requirements because the mixer and the vessel have to work as one system. High shear does the dispersion. Vacuum keeps air and extra heat from undoing it.