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CENTRIFUGES
Centrifuges are instruments used to hasten sedimentation of suspended particles in liquids.
Components of a Centrifuge
Centrifuge consists of the following basic components:
(i) Central shaft spindle, which rotates at high speed
(ii) Head fixed to a shaft with its arms holding to buckets
(iii) Mechanisms for rotating the spindle, which could be either manual rotating handle or electrical motor
Types of Centrifuges
There are two types of centrifuges:
- Manual (hand) centrifuge
These are operated manually hence, cannot achieve very high speed of rotation and are unsuitable for advanced centrifugation e.g. of blood cells from plasma or serum. They are instead used for sedimentation and concentration of cells and organisms in liquids e.g. Urine, water etc.
- Electrical or electronic centrifuge
They use electric power and therefore can achieve high supersonic speed and are used for advanced separation procedures.
Centrifuges have maximum optimum speed by which they operate called revolutions per minute (rpm).
Care and Maintenance of Centrifuges
Centrifuges require little maintenance if properly used.
They however require regular inspection and lubrication of the motor and the spindle.
To increase its lifespan and effectiveness;
- Avoid uneven loading of the rotating head.
- Always ensure that the centrifuge is balanced before starting the motor.
- Avoid spillages on the centrifuge.
- Avoid using centrifuge’s in corrosive atmospheres becomes these will corrode and weaken the rotating head and motor ensure regular inspections for worn out orloose electrical wiring
- Use appropriate size centrifuge tubes in the socket in the rotating head
- Do not open the centrifuge or stopping the machine mechanically until when rotation have stopped by itself. This practice is dangerous and wears out the brushes.