Meaning
International testing standards define the laboratory procedures for measuring the consistency of lubricating greases at low temperatures. The implementation of ISO 13737 establishes how cone penetration is measured to determine the stiffness of lubricants under cold conditions. This test ensures that the greases used in molding machinery and robotic arms remain functional without seizing up.
Testing Method
The procedure involves cooling a sample of lubricating grease to a specified low temperature and then measuring how far a standard cone penetrates it over a given time. If the grease becomes too stiff, it will not flow to the moving parts of the mold. This failure can cause mechanical wear and unplanned system stops.
To prevent these breakdowns, laboratories run tests on each grease batch before approved use.
Lubrication Selection
Choosing a lubricant that complies with this standard ensures that the ejector pins and slides on a mold operate smoothly in cold environments or during startup. If the grease is too thick, the motors driving the ejection system will draw excessive current and trigger alarms. This choice prevents unnecessary mechanical stress on the mold components.
Defect Prevention
Proper grease consistency prevents grease from bleeding or migrating from the ejector pins onto the molded parts. When grease migrates, it causes cosmetic blemishes on the plastic surface and ruins the part finish. This test standard helps maintain a clean molding environment.
