Consistency (25ºC)Heater & PumpThis is a test to evaluate the hardness of grease. As shown in the figure on the right, a cone is inserted into the grease filled in a container for 5 seconds, and then the cone penetration is calculated from the penetrated depth. The larger the value of cone penetration, the softer the grease is. This is a test to evaluate the degree of oil separation from grease. 10g of grease is placed in a conical wire mesh, as shown on the right, and heated. Then, the amount of oil that drips is measured to calculate the amount separated from the grease. The smaller the value, the lower the grease's tendency to separate. Greases that are easier to separate may allow oil to drip or seep during use. This is a test to evaluate the heat resistance of grease. Grease softens when heated and becomes fluid and drips when it reaches a certain temperature. This temperature is called the dropping point, and it serves as a guide for the upper limit of the service temperature of the grease. Grease is filled inside a cup as shown on the left and heated gradually. The temperature at which the thickener melts and oil drips from the hole of the cup is the dropping point.The ER washout test measures a grease's ability to resist being washed out of a bearing by water.A bearing filled with grease is rotated at 600 rpm, and the specified amount of water is injected at 38ºC or 79ºC for 1 hour to measure the change in mass of the grease. JIS ConsistencyBearing filled with greaseMotorPenetrated vertically for5 seconds5 secondslaterDepth of penetration in5 seconds (mm) × 10 = Cone penetrationLidConical wire meshGreaseBeakerSeparated oilAppearanceSemi-fluid formSoftSlightly softMedium consistencySlightly hardGreaseNo.000No.00No.0No.1No.2No.3445~475400~430355~385310~340265~295220~2509Testing of greases■Cone penetration test (JIS K 2220 7) ■Oil separation test (JIS K 2220 11) ■Dropping point test (JIS K 2220 8) ■Water washout test (JIS K 2220 16)
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