For the determination of the degree of refining (beating) of a pulp suspension in water and expressing it in terms of the Schopper-Riegler (SR) number, and to determine the de-watering time.
The Schopper-Riegler apparatus measures the degree of work done on the fibers during stock preparation (refining degree, measured in SR degrees) and is therefore a primary tool in the evaluation of the characteristics of pulp. The apparatus consists of a drainage chamber and rate measuring funnel on a sturdy support.
The drainage chamber is fitted with a wire screen (100 cm²) at its lower end and is sealed 25 mm above the screen when the sealing cone is lowered. After filling 1 liter of suspension into the drainage chamber the sealing cone is raised pneumatically. As the filtrate drains into the rate measuring funnel a fiber pad is formed on the screen, slowing down the process depending on the mechanical treatment to which the pulp has been subjected. The discharge from the side orifice is collected in a graduated cylinder, measured by an ultrasonic sensor and the result is displayed digital.
