A Simplified Spray-Flammability Test for Hydraulic Fluids

Abstract

Hydraulic lines are known to rupture permitting a stream or spray of hydraulic fluid to encounter the flame of burning fuels or the surface of hot or molten metal. This is a prevalent cause of fires in many industries. High-pressure spray-flammability tests simulate this type of industrial hazard and are able to distinguish the difference in fire resistance among the various kinds of hydraulic fluids. The available high-pressure spray tests are inconvenient to use, however, since they usually must be done outdoors where they are subject to the vagaries of the weather. If done indoors, the tests must be performed in specially assembled fireproof areas. In addition, relatively large volumes of test fluids are needed, and the high-pressure pump, motor, and auxiliary equipment can become costly. A low-pressure spray-flammability test that can be conducted safely in a conventional laboratory hood is described. The equipment required is simple and inexpensive and only limited amounts of fluid and fuel are needed. The flame from a laboratory gasair burner serves as the source of ignition. The data obtained correlate very well with those from a conventional high-pressure spray-flammability apparatus. Results from both kinds of tests evaluating the several types of fire-resistant hydraulic fluids are presented in tabular and pictorial forms. A variety of test conditions is not available with the new method described, but the conditions are chosen so that they simulate practical industrial situations and provide correlation with other flammability tests at a sufficient confidence level.