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      Specification

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Transformer Oil Purchase Specification

COMPOSITION

Insulating oils for general application which are covered by this specification are manufactured from predominantly naphthenic base crudes. Distillates from these crudes may be acid refined, hydrogen treated, solvent extracted, or processed by other suitable refining methods to yield acceptable mineral insulating oils which meet the test requirement at the point of delivery.

Oils from paraffinic crudes may also be covered by this specification with the exception of performance at low temperatures. Other requirements may be needed for these products to ensure proper function at low temperatures.

ADDITIVES

The use of all additives must be identified. An additive is a suitable chemical substance which is deliberately added to a mineral insulating oil to improve certain characteristics.

Oxidation stability

Uninhibited oils must be free of additives, either natural or synthetic that are used to improve oxidation stability. This includes but is not limited to 2,6 ditetiary-butyl phenol, 2,6 dietertiary-butyl cresol, or metal deactivators such as benzotriazole and its derivatives.

Inhibited oils are insulating oils which have been supplemented with either 2,6 ditetiary-butyl phenol or 2,6 dietertiary-butyl cresol or any other specified and acceptable oxidation inhibitor. If an additive other than 2,6 ditetiary-butyl phenol or 2,6 dietertiary-butyl cresol is used, appropriate limit values for oxidation stability tests (those for Type I or Type II oils) should be agreed to by the purchaser and seller. If more than one additive is used, the more stringent limits for oxidation stability, those for the Type II oils would apply.

Pour point depressants, gassing tendency improvers, additives for corrosive sulfur and static electrification (metal passivators), antifoaming agents and other additives

All additives should be specifically identified or at a minimum identified by class of compounds such as metal passivator if the specific information is proprietary.

PRODUCTION AND SHIPPING

Insulating oils covered by this specification shall be produced from proven crudes by suitable refining techniques, both of which shall have been approved by the purchaser. After such approval, no change in crude source, processing, or refining methods shall be made that results in a substantial change in the product characteristics without the prior approval of the purchaser.

Shipping containers should be dedicated to new transformer oils. The shipping method and containers shall be agreed upon by purchaser and seller and shall not be changed without prior approval of the purchaser.

For more information related to Doble TOPS, please click on the PDF file in the "Related Links" box on upper right hand corner of  this page.