|Cup Number||Seconds Range||Centistoke Range||Midrange Sensitivity ¹||Calibration Oil Number/ Centistokes ²|
|1||25 to 110||7 to 165||1.6||G-35-P/64|
|2||25 to 120||117 to 582||4.8||G-100-P/270|
|¹ Stated as Centistokes per second of efflux time|
² Centistoke Values are nominal - actual values printed on labels
Guide for removing the G-series calibrating oil from Gardco viscosity cups.
Any remaining material in the cup must be removed by flushing with a suitable solvent. Light naphtha, heptane, octane, highly aromatic solvents, and or any other petroleum-derived hydrocarbon solvent can be used. Varsol® is a commercial solvent that works very well for this purpose.
Completely dry the viscosity cup with a lint free cloth. Use a highly volatile solvent for a second cleaning as since any remaining hydrocarbon solvents from the first process will evaporate quickly after the sample has been flushed from the cup. Hypersolve, MEK and Alcohol can be used in aluminum cups and Hypersolve and Alcohol for the stainless steel cups. Acetone is commonly used as the second solvent because of its high volatility and its ability to dissolve traces of petroleum solvents and water.
In the third process a low velocity stream of clean air will be sufficient to evaporate remaining traces of any volatile solvent. Be aware, avoid rapid evaporation of these solvents as this can cool the surface to such an extent that humid air may be brought below the dew point, causing a film of water to form on the cup.
Varsol is a registered trademark of the Exxon Company
Meets and exceeds ASTM D 1084 method A and Federal Specifications MMM-A-189C