STABILITY, STORAGE STABILITY OF RESIDUAL FUELS BY SPOT TEST: ASTM D4740
EXPLANATION
This test method describes separate procedures for determining the cleanliness of residual fuel oil and its compatibility with a blend stock. It is applicable to fuel oils with viscosities up to 50 cSt at 100° C. These procedures used alone or together are used to identify fuels or blends that could result in excessive centrifuge loading, strainer plugging, tank sludge formation, or similar operating problems.
TEST SUMMARY
In the cleanliness procedure, a drop of the preheated sample is put on a test paper and placed in an oven at 100° C. After 1 h, the test paper is removed from the oven and the resultant spot is examined for evidence of suspended solids and rated for cleanliness using the Adjunct Reference Spots in Test Method ASTM D4740.
In the compatibility procedure, a blend composed of equal volumes of the fuel oil sample and the blend stock is tested and rated in the same way as just described.
TEST PRECISION
Repeatability: 1 rating number
Reproducibility: 1 rating number
The bias of this test method has not been determined.
