Lubricant Testing 101: Penetration (P0 & P60) by Nye Lubricants

This video features penetration tests. Penetration tests are conducted by Nye technicians in order to test the consistency in stiffness of a grease. The P0 and P60 tests follow ASTM D-217 method full scale or ASTM D-1403 method half and quarter scale. They are two of the four required tests performed on every single batch at Nye prior to shipping. For more, visit us at NyeLubricants.com Nye Lubricants performs a vast array of tests in-house on our lubricants. A full complement of laboratory equipment enables us to complete qualification testing to ensure design and performance requirements of your application are met. The penetration test begins with the grease, at 25◦C, (plus or minus 1◦C), being leveled into a cup. The sample size and cone weight for this test is determined by your application needs. Using a penetrometer, a cone is dropped into the cup for 5 seconds, creating a hole in the grease. The technician records the depth (in a tenth of a millimeter) of this hole. This value is known as the P0 or unworked penetration. The grease is then sheared using a mechanical worker through 60 double strokes, simulating the use of the grease. When this is completed, the technician repeats the cone test to determine the P60 value, also known as worked penetration. Nye technicians can also carry out P10,000 and P100,000 tests, depending on the application specifications. The penetration value of P60 is rated using the NLGI grade chart from 000 to 6. These values determine the stiffness of the grease and how a grease will react over time to wear and service. The higher the penetration value, the softer the grease. The lower the penetration value, the stiffer the grease. A grease that is too soft may migrate away from the area that needs to be lubricated. A grease that is too stiff may not effectively migrate into those areas that need to be lubricated.