Device for use in the centrifugal separation of components of a liquid

For use in centrifugal separation of a liquid having at least two components having different specific weights,

• a device comprising:
• wall means of a predetermined thickness of synthetic plastic material defining a separator tube having an inner face of generally round transverse cross-sectional figure;
• a generally cylindrical, piston-like, substantially rigid, separator element having a specific weight which lies between the respective specific weights of said two components;
• said separator element having an outer peripheral surface with a generally round transverse cross-sectional figure;
• said separator element outer peripheral surface having at least an axially intermediate portion thereof which is of substantially the same diameter as said inner face of said separator tube wall means;
• said separator element being frictionally, axially slidably received in said separator tube;
• said separator element being comparatively rigid relative to said separator tube wall means and said separator tube wall means being sufficiently flexible relative to said separator element, to enable substantially only that portion of said tube wall means conincident to said separator element to flex and thereby increase in diameter sufficient to enable passage of liquid between said that portion and said separator element, in response to centrifugal force.