Restricted Passage Research Articles

RHEOPECTIC GREASE

A Rheopectic Grease is one that solidifies upon flowing, or at least that is its meaning expressed practically. The advantages of such a grease are mainly concerned with its use in mechanical lubricators, because they can be easily pumped and yet will not drip when they reach the bearing. Greases have the disadvantage that they may be difficult to pump and may not easily flow through restricted passages in the pump. It is in view of the possibility of fitting chassis lubricators to motor cars in the future that a study of rheopectic greases may prove timely. The subject has been reviewed by Neesley, Brunstrum and Liehe (all of the Research Department, Standard Oil Company, Indiana), in a paper to the S.A.E. at Atlantic City in June. The American chassis lubricator, the Multi‐Luber (described in our August issue) was partly responsible for this work, and the authors describe how this new lubricant functions in this unit.

Abridgment of development of the new autovalve arrester

This paper describes the development of a new autovalve lightning arrester operating on the principle of discharge in restricted passages. A brief resume is given of the improvements in performance and size desired in lightning arresters. Reference is made to laboratory tests on insulation protected with arresters to determine the limits of discharge voltage required for good local protection. Oscillograms show that the new autovalve arresters meet these requirements. Successful operating experience with these arresters is staled to give final verification of the results obtained in the laboratory investigations. The steps in the development of materials are described and the materials finally chosen and the design of arresters are considered. The performance is discussed and illustrated by oscillograms covering a wide range of currents, both with and without power voltage applied. The size of the new arresters is about one-half that of the present commercial autovalve arresters. One of the probable benefits resulting from this reduction in size is the possibility of making practicable the protection of high-voltage lines against lightning flashover.

Development of the New Autovalve Arrester

This paper describes the development of a new auto-valve lightning arrester operating on the principle of discharge in restricted passages. A brief resume is given of the improvements in performance and size desired in lightning arresters. Reference is made to laboratory tests on insulation protected with arresters to determine the limits of discharge voltage required for good local protection. Oscillograms show that the new autovalve arresters meet these requirements. Successful operating experience with these arresters is stated to give final verification of the results obtained in the laboratory investigations. The steps in the development of materials are described and the materials finally chosen and the design of arresters are considered. The performance is discussed and illustrated by oscillograms covering a wide range of currents, both with and without power voltage applied. The size of the new arresters is about one-half that of the present commercial autovalve arresters. One of the probable benefits resulting from this reduction in size is the possibility of making practicable the protection of high-voltage lines against lightning flashover.