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Renin Angiotensin Mechanism.

Sieve Shaker.

 

Principle:

  • Agitation by Oscillation.

  • Particles are made to pass through different sieves placed in nests which oscillate back and forth in motion.

Construction:

  • Consists of a metal frame on which sieves of different no. can be mounted.

  • The sieves are arranged in a dissenting order of mesh size.

  • The metal frame is fixed using screws and a capping on a vibrating frame.

  • The vibrating frame is operated by an electrical motor whose speed can be controlled.

  • The timer helps in maintaining time of the operation.

Working:

  • The powder to be screened is kept on the uppermost sieve and is capped and bolted.

  • The machine's timer is set to the desired time (Usually 20 mins) and operated at desired speed.

  • The vibrations cause oscillations resulting in passing of material from one sieve to another.

  • After a given time the machine is stopped, the metal frame is loosed and screens are separated to collect the material.

Advantages:

  • Easy operation.

  • Less power consumption.

  • Economical.

Disadvantages:

  • Fines may generate due to attrition.

  • Clogging may happen if powder is not sufficiently dried.

Commonly Asked Questions.

  1. With a well labelled diagram describe construction and working of “Sieve Shaker”.

  2. Write a short note on “Sieve Shaker”.
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