Humidity-Induced Dimensional Changes in Cotton-Phenolic Ball-Bearing Retainers

摘要

The sensitivity of clean and oil-impregnated cotton-phenolic retainers to atmospheric humidity has been measured. The cleaning procedure used here, and vacuum oil-impregnation did not change the dimensions of the retainers. Absorption of water caused the diameter of the retainers to increase by 0.2 to 0.4 percent, depending on the humidity. Oil impregnation of the retainers retarded, but did not stop, the absorption of water. Oil was displaced from the impregnated retainers by water; one-third to one-half of the oil was removed, depending on the atmospheric humidity.