SIGMA BLADE MIXER

Presented ByMastan Vali K

Abhilash N

• The sigma blade mixer is a commonly used mixer for high viscosity materials.

• One of the most popular used for mixing and kneading of high viscosity

materials.

• It belongs to the family of double arm kneader mixers.

PRINCIPLE:

• The mechanism of mixing is shearing.

• The inter meshing of sigma shaped blades creates high shear and kneading

actions.

• The mixing action is a combination of bulk movement, shearing, stretching,

folding, dividing, and recombining as the material is pulled and squeezed

against blades, saddle, and side walls.

CONSTRUCTION • The design is mostly based on the curvature and concavity of the kneading blades.

• It consists of double trough shaped stationary bowl. • Two sigma shaped blades are fitted horizontally in each trough of the bowl.• These are connected to a fixed speed drive.• The mixer is loaded from the top and unloaded by tilting the entire bowl by

means of a rack and pinion drive.• It consist of saddle shaped container made of either Mild Steel or Stainless

Steel 304 or 316 with jacket of covering two side for heating or cooling application & dust free cover to get Vacuum if desired or normal cover.

• The mixing elements (Blades) are of Sigma type Steel casted and duly finished two in number which contra rotate inward fitted at close or specified clearance with the container to give thorough and uniform mixing.

• There is a Gland pusher of Gun Metal Bush which ensure minimal friction and extend the life of mixing elements (Blades) Shaft.

• The complete Mixer is Mounted on Steel Fabricated stand of suitable strength to withstand the vibration and give noise free performance.

Different types of Sigma Blade s:

Two wing bladeSigma- or Z-form blade Double naben

• The shape of the kneading blades enables a steady flow of material from the side walls of the kneading trough to the middle of the trough.

DRIVE:The Drive Consists of Motor of type TEFC Or TEFC Flameproof of Specified

440 RPM, Reduction Gear Box of Reputed Make having suitable size and ratio, Spur Gears, are also provided of adequate size and having machine cut teeth, between the front and rear blade complete with guard suitable for grease lubrication.

WORKING:

Different powders are introduced from the top of the trough.The body is covered because considerable dust may be involved during dry blending and granulating solution may evaporate during wet granulation.The kneading blades first squash the mass flat and then roll it on itself and squash once again.It tears the mass apart, and shear it in between the moving blades and the stationary surface walls.Through the fixed speed drive, the sigma blades are allowed to rotate.The blade move at different speeds.The effectiveness of mixing depends upon the kneader blade design, sometimes they are made very rugged, and of different shapes.The edges of the blades may be more serrated to give higher shredding action.

KEY FEATURES INCLUDE:•Working capacity of up to 5,000 liters (1,321 gallons) and custom models

available up to 10,000 liters (2,642 gallons).

•Choice of stationary or tilting units for loading and unloading to suit your

production needs; bottom valve discharge units also available.

•Mono-screw extruder models available.

•Built to international code standards – CODAP, ASME, and other Standards.

•Modular design enables easy customization to suit desired application.

•Jacketed trough design for heating or cooling.

•Independent blade arm drive with differential rotating speeds and

adjustable ratio.

Applications of the Sigma Mixer:

•Adhesives•Biscuit dough•Butyl rubber•Bakery•Carbon pastes•Ceramics•Chemicals•Chewing gum•Crayon and pencil lead•Explosives•Fiberglass resin dough's•Food and confectionery products•Gaskets and gland packing's•Grinding wheel preparations•Hot-Melts•Inks and pigment products

•Marzipan•Mastics•Metal powders•Moulding preparations•Pencil erasers•Pharmaceuticals•Plastics•Sealing compounds•Silicone rubber•Soaps and detergents•Solid propellants•Sugar pastes•Viscous rubber solutions

ADVANTAGES •Sigma blade mixer creates a minimum dead space during mixing

•Ideal for mixing, kneading, of highly viscous mass, sticky & dough like products

DISADVANTAGES•Sigma blade mixer works at a fixed speed

•Extruding

•These mixers and their variants (double arm kneader mixer extruders) are capable of handling material with viscosities as high as 10 million centipoises.

•The power consumption in double arm kneader mixer is very high compared to other types of mixers and can range from 45 to 75 kW/m3 of mix material.

Manufacturers• Paresh Engineering Co.http://www.pareshenggco.com/sigmamixer.php • Vitro Pharma Machinery.http://www.vitropharmamachinery.com/sigma_mixer.html • Prism Pharma Machineryhttp://www.mixerblenderdryer.com/sigma-mixer-z-blade-dough-mixer.html • Ambica Boiler & Fabricatorhttp://www.abfindia.co.in/sigma-mixer.html • Teknik Pharma Machineryhttp://microteknik.com/168-mixing-vat-with-stirrer-manufacturer-supplier-exporter-in-kerala-.html

THANK YOU