The availability of new technologies and tools means that more and more use is being made of non-cutting metalworking processes which permit more cost-effective workpiece production and help to increase productivity. For the perfect mastery of forming processes, effective metalworking media are required which, among other things, provide adequate protection against adhesive wear.
Most forming processes are characterized by:
- low relative speeds
- relatively low temperature
- high surface pressures
- highly activated metal surfaces
- boundary friction conditions with low hydrodynamic component
These conditions are simulated in the “press-in” test (Fig. 1): An oversize bolt is pushed in and back out of a matrix at a constant running speed in the range of 20...200 mm/min (typically 50 mm/min). During this process, the pushing force increases sharply as speed decreases, which can be attributed to the reduction in hydrodynamic lubrication. The pressing force and the relative surface wear on the interacting components are used as a quality criterion for the load-bearing and antiwear capacity of the lubricant being tested.
The “press-in” test is a test method for qualitatively assessing the suitability of additives for forming processes such as vacuum forming, pipe drawing, precision cutting, forming at high internal pressures, etc.
