Control of Foaming by Adding Known Mixtures of Pure Chemicals
Abstract
Different methods of testing and selection were used to investigate the problem of obtaining satisfactory mixtures of pure chemicals capable of inhibiting both the foaming volume and the foam stability of aeronautical lubricating oil. The method of testing foam volume at room temperature, the bubbling method at high temperatures (100 and 140 deg C, 212 and 284 deg F, respectively), and the beating and evacuation method were used. Thirteen substitutes for glycerol and twenty-seven substitutes for Aerosol OT were tested for defoaming ability at 140 deg C (284 deg F) on Aeroshell 120 oil, using a porous ball bubbler. All defoaming emulsions were run to exhaustion of the effect and their durations as antifoam agents recorded. In a ratio of 4 parts glycerol (or substitute) to 1 part Aerosol OT (or substitute) at total concentrations of 1000 to 1500 parts per million, the best of these emulsions completely inhibited foam formation. The best combination was sorbitol and Aerosol OT, 800 and 200 parts per million, respectively, which is an excellent defoamer for 4 hours but leaves a sticky residue in the meter. Glycerol evaporates in 7 minutes at 140 deg C and in 30 minutes at 100 deg C leaving no residue. Tests at room temperature have also been conducted and have been of use in suggesting possible substitutions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1949
- Accession Number
- ADA801542
Entities
People
- A. P. Brady
- J. W. Mcbain
- R. B. Dean
- Sydney Ross
Organizations
- Stanford University