ISO 5351 Glass Viscometers with Jacket and tap are suitable for the determination of pulp viscosity in full compliance with ISO 5351. PSL Rheotek Pulp Viscometers with Jacket & Tap are manufactured in the UK to the specifications of ISO 5351. The limiting viscosity number of the pulp or cellulose sample is obtained by dissolving the sample in cupriethylene diamine and then determining the flow time. This method has superseeded SCAN CM15:99. Require an external circulator to provide circulating water at a constant temperature of 25 degrees C for conducting the test procedure. The viscosity of pulp is one of the most important test parameters for international commodities trading.