5.1 Horizontal metal surfaces, on which water droplets tend to be retained, are more prone to rusting and corrosion than vertical or sloping surfaces. This test method is therefore more discriminating than Test Method D665 (Procedure A), since it gives a separate evaluation of the oil on a horizontal and a vertical surface. The test method indicates the ability of oils to prevent rusting and corrosion of all ferrous surfaces in steam turbines under full flow and quasi-static conditions. It is used for specification of new oils.

1.1 This test method covers the ability of steam-turbine oils to prevent the rusting of horizontal and vertical ferrous surfaces when water becomes mixed with the oil.

1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.