Penetrometers / Grease Workers
the degree to which a highly viscous or creamy, pasty, semi-solid sample resists deformation by an applied force and the measure of consistency is called penetration.
To determine the consistency of grease for example, a penetration measurement is taken by allowing a cone assembly of a given weight to sink into the grease for a determined amount of time at a determined temperature. The depth to which tho cone sinks into the grease is the penetration. The deeper the cone sinks the softer the material is.