The effect of lubricating oil on the puncture strength of paper insulation

Due to the fact that only comparative results were sought, the investigation was greatly simplified. On a comparative basis, the effects of external influences were largely eliminated from positions of vital importance and the use of an elaborate test, circuit was unnecessary. The equipment consisted of a high-voltage test transformer which supplied the test voltage; an induction regulator, auto transformer and generator field rheostats for voltage control; overload relay and aircore inductances for circuit protection; motor-generator set for a source of 60 cycle alternating voltage. The electrodes were circular, square edge brass discs. Specimens were immersed in lubricating oil for periods up to 40 hours and then tested for puncture strength. Following this, specimens were immersed for one hour and 24 hours and each of the two groups tested at intervals of time up to 720 hours. In each test the voltage was raised in steps of 200 volts, starting at 1000 volts. The puncture strength of the untreated paper was determined by testing a sufficient number of specimens over a period of days. The results obtained indicated no immediate deleterious effects of lubricating oil on paper. On the contrary, there was an improvement in puncture strength, accounted for by the fact that the relatively low voltages-used did not make ionization a serious factor. The results of tho long-time tests were unsatisfactory, as explained previously. However, they did permit the conclusion that deterioration of paper impregnated with lubricating oil would become apparent much sooner than if insulating oil were used. Oxidation, although probably existing, was apparently too slow to affect the results.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical Engineering

Department dc:contributor.department

Electrical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1939

Author dc:creator

• Koslow, Herman M.

Committee members dc:contributor.committeemember

• Murray, W. A.
• Norris, Earle Bertram
• O'Shaughnessy, Louis

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-06092012-141024

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/42965