ASTM D901-91(1997) - 10.4.1997
 
1. Scope

1.1 These methods cover procedures for testing askarels that are used in transformers and certain other electrical apparatus as an insulating and cooling medium. These methods are generally suitable for specification acceptance, factory control, reference testing, and research. The procedures appear in the following sections:

Test Method

ASTM Designation of Test Method

Chemical Tests:

Neutralization Number

D664, D974

Water Content

D1533

Scavenger Content

D1701

Chrlorine Compounds, Hydrolyzable

D1820, D2441

Chlorides, Inorganic

D1821

Thermal Stability

D1936

Electrical Tests:

Dielectric Breakdown Voltage

D877

Dissipation Factor and Relative Permittivity

D924

Specific Resistance

D1169

Physical Tests:

Viscosity

D88, D455

Fire Point

D92

Pour Point

D97

Sampling

D923

Refractive Index

D1218

Visual Examination

D1702

Specific Gravity

D1810

Coefficient of Thermal Expansion

D1903

Color

D2129

Polychlorinated Biphenyls in Environmental Materials

D3304

Polychlorinated Biphenyls in Mineral

Insulating Oils by Gas Chromatography

D4059

For askarels having a Saybolt Universal viscosity of over 110 s at 100oF, modifications of certain test procedures are necessary.

1.2 As a precaution, insulating systems incorporating askarels and cellulose or other organic materials should be purged to remove any traces of flammable gases by bubbling dry nitrogen through the askarel and flushing the gas space with dry nitrogen before any work is performed on the apparatus.

1.3 Current governmental regulations prohibit the manufacture and sale of polychlorinated biphenyls (PCBs). This method serves as a reference for all askarels, PCB and non-PCB.

Note 1--Various materials have been used successfully in taking, storing, and testing samples of askarels. Until experience has developed a strong preference, materials referred to in these methods will be understood to be approved but not specified.

Note 2--Methods for handling and disposal of askarels and askarel-impregnated materials are given in a recent ANSI Committee C-107 Guide, Guidelines for Handling and Disposal of Capacitor and Transformer-Grade Askarels Containing Polychlorinated Biphenyls.

Note 3--For specifications for askarels, see Specifications D2233 and D2283.

1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 1.2.