There are 5 faces to consider at the cutting end, but only 3 of them require grinding. The back (4) surface and bottom (5) surface can be left untouched. The remaining three faces require grinding along two axis each, however they can still be created within three grinding operations.On most tools there is also a fourth grinding operation which is a radius on the tool tip. This radius increases tool life and improves surface finish. grinding is done with the help of a tool grinding rest, which can be set to a required angle.
Since very small needle lift is obtained in the test equipment result in an unequal pressure distribution in the cut off shaft resulting in a hard contact in a small area along with high frequency oscillations, low lubricity of test oil will increase the chance of seizure. Full lift and high lubricity of heavy oil eliminates this risk of seizure during normal operation.( Always open and clean slide type valves before testing as cold sticky heavy oil along with small clearances can cause restriction in the movement of the spindle).
Comments