4. Summary of Test Method
4.1 For unworked penetration, the sample is brought to 25 more or less 0.5°C (77 more or less 1°F) in a worker cup or other suitable container. The cone assembly of the penetrometer is released and allowed to drop freely into the grease for 5 more or less 0.1 s. Three determinations are made and averaged to give the reported result.
4.2 For worked penetration, the sample is brought to 25 more or less 0.5°C (77 more or less 1°F) and placed in the worker cup. The sample is subjected to 60 double strokes in the grease worker. The penetration is determined immediately by releasing the cone assembly from the penetrometer and allowing the cone to drop freely into the grease for 5 more or less 0.1 s. Three determinations are made and averaged to give the reported result.
4.3 For prolonged worked penetration, the sample is placed in the worker cup and subjected to a predetermined number of double strokes in the grease worker. Following completion of the prolonged working, the grease and worker assembly are brought to 25 more or less 0.5°C (77 more or less 1°F) and the grease is worked an additional 60 double strokes in the grease worker. The penetration is determined immediately by releasing the cone assembly from the penetrometer and allowing the cone to drop freely into the grease for 5 more or less 0.1 s. Three determinations are made and averaged to give the reported result.
4.4 For block penetration, a cube of the grease is prepared by slicing off a thin layer using the grease cutter. The cube of grease is brought to 25 more or less 0.5°C (77 more or less 1°F) and placed on the penetrometer table with the prepared face upward. The penetration is determined by releasing the cone assembly from the penetrometer and allowing the cone to drop freely into the grease for 5 more or less 0.1 s. Three determinations are made and averaged to give the reported result.
