How To Clean The Sigma Mixers

Cleaning a sigma mixer (z blade mixer / kneader) depends on what kind of material you’re processing (food, rubber, adhesives, resins, explosives, etc.) and whether the mixer is standard or vacuum/heat-jacketed. Here’s a general guide you can adapt to your application: 

1. Manual Cleaning – the usual way

If your mixer doesn’t have auto-cleaning, here’s the simple routine most people follow:

• Turn it off & empty it
  Shut the power, unplug it, and get as much material out as you can.

• Scrape out leftovers
  Use a scraper (plastic or stainless). Don’t use sharp tools—they’ll scratch the mixer.

• Wash it down

• Food or cosmetics? → warm water + a bit of soap usually does the trick.

• Sticky stuff like rubber, glue, or resin? → you’ll need the right solvent (alcohol, acetone, etc.).
  Pro tip: throw in some water or solvent, run the mixer slowly, and let the blades help clean themselves.

• Scrub the hard-to-reach spots
  Corners, blade edges, discharge valve—use a brush or cloth.

• Rinse well
  Flush with clean water (or neutralizer if you used a strong solvent). Make sure nothing is left behind.

• Dry it out
  Wipe with a clean cloth. If your mixer has heating, turn it on a bit to speed things up. Keep the lid open for airflow.

• Quick check
  Make sure blades, seals, and valves are clean before the next run.

2. CIP Automatic Cleaning – the easy way

Some sigma mixers can come with a CIP system. That just means Clean-In-Place, or in simple words: the mixer washes itself.

It has built-in spray balls or nozzles that blast water or cleaning liquid over the blades, the trough, and the valve. The steps usually go like this:

1. Rinse → wash out the big leftovers.

2. Wash → cleaning liquid breaks down sticky stuff.

3. Rinse again → flush everything clean.

4. Sanitize (if needed) → food/pharma often add this step.

5. Dry → air or heating keeps the mixer ready to go.

3. Why CIP is handy

• No more climbing in to scrub by hand.

• Safer—you’re not touching solvents or sticky product.

• Cleaner—great for food, pharma, and cosmetics.

• Faster—less downtime between batches.

In short: manual cleaning works fine for most chemical jobs, but if you’re in food, pharma, or cosmetics, a CIP system makes cleaning way easier, safer, and more reliable.

frank@karvi.com

www.isgmazs.coM