AFS Foundry Sand Testing Equipment Operating Instructions Manual

RIDSDALE-DIETERTFOUNDRY HYDROMETER (0 – 90 Baumé)IGENERAL PRINCIPLESThe instrument is used to determine the specific gravityof all types of foundry washes, sprays and coatingmaterials which are heavier than water.IIDESCRIPTIONThe hydrometer consists of a transparent plastic tubingwhich is resistant to organic solvents and has a speciallydesigned stainless steel tip for stability.IIITEST PROCEDURE(a)(b)(c)(d)(e)(f)(g)(h)Check the hydrometer and ensure that it is clean and dry.Gently stir the sample for five minutes. Care should be takento ensure that no air is introduced into the sample.Stop the stirring unit and allow the sample to come to rest (no detectable motion).Place the hydrometer into the sample. Care should be taken to position thehydrometer at least half an inch from the edge of the container or the mixer blade.When placing the hydrometer in the liquid ensure that it does not drop too far. Thehydrometer should be allowed to slide gently from the hand so that it settles slowlyinto the liquid after being released.If the hydrometer is observed to rise after its initial release it has not been properlyplaced in the sample and the test must be repeated starting at step (a).After the hydrometer is placed in the sample it should be allowed to settle for oneminute. At this time the value can be read directly from the hydrometer scale.After the value has been taken measure the temperature of the sample and record.131