6. Apparatus
6.1 Penetrometer, in accordance with A1.1. The instrument shall be capable of indicating depth in tenths of a millimetre. A sketch of a generic penetrometer is shown in Fig. 1.
6.2 Standard Penetrometer Cone, in accordance with A1.2, is suitable for all penetrations. An optional penetrometer cone, in accordance with A1.3, is suitable only for penetrations less than 400. The optional cone should not be used to measure the penetration of 00 and 000 grade greases.
6.3 Grease Worker, comprising a grease cup, cover, and plunger assembly, in accordance with A1.4, constructed for either manual or mechanical operation.
6.3.1 Grease Worker Drive, Manual, in accordance with A1.5, which allows for working the grease at a rate of 60 more or less 10 double strokes per minute.
6.3.2 Grease Worker Drive, Motorized, in accordance with A1.6, which allows for working the grease at a rate of 60 more or less 10 double strokes per minute. This apparatus is essential for the working step of the prolonged worked penetration procedure.
6.4 Grease Cutter, in accordance with A1.7, is used for preparation of samples for block penetration.
6.5 Temperature Bath, either a water bath or an air bath capable of controlling the bath temperature at 25 more or less 0.5°C (77 more or less 1°F) and designed to bring the assembled grease worker to test temperature conveniently. If a water bath is to be used for samples for unworked penetration, means should be provided for protecting the grease surface from water and for maintaining the air above the sample at test temperature. An air bath is preferred for bringing block greases to test temperature, but a tightly sealed container placed in a water bath will suffice. A constant-temperature test room may be used instead of the temperature bath.
6.6 Spatula, corrosion-resistant, having a stiff blade nominally 32 mm (1.25 in.) wide and at least 150 mm (6 in.) long.
6.7 Temperature-Measuring Device, with a sheath length of approximately 200 mm (8 in.) and a sheath diameter of approximately 3.7 mm (0.145 in.) (small enough to fit through the vent cock). The temperature range of the device should be wide enough to allow it to be immersed in grease at approximately 38°C (100°F) without damage. The scale should have small enough divisions (or digital resolution) to allow the user to read more or less 0.5°C (more or less 1°F). A spacer can be applied to the upper portion of the sheath to hold the tip just above the perforated plate of the grease worker and in the bulk of the sample (see A1.3).
6.8 Overflow Ring (optional), in accordance with A1.8, is a useful device for catching grease scraped from the sample surface as well as any grease forced by the penetrometer cone to overflow from the cup. This grease can be returned to the worker cup for subsequent testing.
7. Reagents and Materials
7.1 Appropriate Volatile Gum-free Solvent, for example, light petroleum naphtha.
7.2 Cloth or Paper Wiper, for wiping grease from the penetrometer cone. The wiper should be soft, so as not to scratch the cone.
