The Falling Ball ViscometerSource: Brookfield Engineering Laboratories, Inc.
Falling Ball Viscometer, Models KF10 and KF20, comply with the German industry standard DIN 53015. The measuring principle, according to Höppler, is to determine the falling time of a ball in a cylindrical glass tube filled with liquid. The working angle of the falling tube in the KF10 is fixed in the DIN 53015 position of 80° relative to horizontal. The water jacket, surrounding the falling tube, when connected to a Brookfield circulating temperature bath provides for precise temperature control of the sample.
The user calculates the dynamic viscosity of the sample by determining the falling time of the ball between the upper and lower ring marks displayed on the falling tube. Using data on the ball constants, the density difference between the liquid sample and the ball, and the working angle constant, a mathematical equation is used to convert the time measurement to a viscosity value in centipoise.