1. MECHANICAL OPERATIONS Abhijit Panchmatiya(130280105030)
SIGMA BLADE MIXER
Faculty : Prof. S. M. Dutta
By:
Ankit Mistry( )
Anil Nakum( )
Divyesh Paghdal( )
Abhijit Panchmatiya( )
Shailesh Parajiya( )

2. SIGMA BLADE MIXER PRINCIPLE The mechanism of mixing is shearing.
The inter meshing of sigma shaped blades creates high shear and kneading actions.

3. CONSTRUCTION

4. 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 of the top and unloaded by tilting the entire bowl by means of a rack and pinion drive.

5. SIGMA MIXER consist of "W" shaped container made of either Mild Steel or Stainless Steel 304 or 316 with jacket of Carbon Steel 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.

6. DRIVE
The Drive Consists of Motor of type TEFC Or TEFC Flameproof of Specified HP 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.
STAND
The complete Mixer is Mounted on Steel Fabricated stand of suitable strength to withstand the vibration and give noise free performance.

7. 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.
Through the fixed speed drive, the sigma blades are allowed to rotate.
The blade move at different speeds.

8. 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

9. Built to international code standards – CODAP, ASME, TUV and others
Modular design enables easy custumisation to suit your application
Jacketed trough design for heating or cooling
Independent blade arm drive with differential rotating speeds and adjustable ratio.
 Smooth trough interior

10. USES, ADVANTAGES AND DISADVANTAGES
Sigma blade mixer is commonly used for mixing of dough ingredients in the baking industry.
2. It is primary used for liquid – solid mixing, and solid - solid mixing.
Sigma blade mixer creates a minimum dead space during mixing.
Sigma blade mixer works at a fixed speed.

11. THANKS