Kneader mixer has two mixing blades rotate towards each other at differential speeds inside a W-shaped trough. Each blade moves the material in opposite direction thereby providing excellent cross mixing of all raw materials. The blades pass the trough walls and each other at close clearances resulting in good mixing. The close clearance produces a shearing  action that is beneficial to the size reduction of solids. This mixer is most suitable for highly viscous material and dough like masses. Selection of appropriate blade shape and speeds result in excellent mixing. On completion of the mix cycle, the trough of the mixer is tilted and the product is discharged. The mixer is also available with a bottom opening design for discharge.

Sigma Mixer Design & Operation

Standard Features

  • Available in all grades of Carbon Steel and Stainless Steel.
  • Optional wear resistant liner plates provided for abrasive products.
  • Designed for atmospheric operation.
  • Stainless steel surfaces are polished to desired standards. All exterior non-stainless surfaces are painted with enamel paint.
  • Squirrel Cage, Three Phase Induction Motors suitable for 415 Volts, 50 Hz.
  • Worm reduction gearbox, helical reduction gearbox.
  • Single Speed Drive.
  • Available in working capacities of 5 Liters to 2500 Liters. Other sizes manufactured on request.

Customised Features

  • Good Manufacturing Practice (GMP) models.
  • Explosion-proof motors, Variable Speed Drives along with Electrical Control Panel.
  • CE
  • Jacketed construction available for heating and cooling applications.
  • Different shape blades available to suit specific applications.
  • Can be offered for vacuum application.


  • Ideal for mixing, kneading of highly viscous mass, sticky and dough like products.
  • Mixing of pastes, rubber, and heavy plastic masses.
  • Applications in Food, Rubber, Pharmaceutical and Chemical industries.
  • Dry powder to wet phase mixing.

Sample applications of Sigma mixers

  • Adhesives
  • Biscuits doughs
  • rubber
  • Carbon pastes
  • Ceramics
  • Chemicals
  • Crayon and pencil lead
  • Inks and pigment products
  • Explosives
  • Fiberglass resin doughs
  • Food and confectionery products
  • Gaskets and gland packings
  • Grinding wheel preparations
  • Hot-melts
  • Marzipan
  • Putties
  • Mastics
  • Metal powders
  • Moulding preparations
  • Pencil erasers
  • Pharmaceuticals
  • Plastics
  • Refractories
  • Sealing compounds
  • Silicone rubber
  • Soaps and detergents
  • Solid propellants
  • Sugar pastes
  • Viscous rubber solutions
  • Chewing gum


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