Astm

Designation: D36/D36M − 12

Standard Test Method for

Softening Point of Bitumen (Ring-and-Ball Apparatus)1
This standard is issued under the fixed designation D36/D36M; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon (´) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense.

1. Scope 1.1 This test method covers the determination of the softening point of bitumen in the range from 30 to 157°C [86 to 315°F] using the ring-and-ball apparatus immersed in distilled water [30 to 80°C] or USP glycerin (above 80 to157°C). 1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 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 and health practices and determine the applicability of regulatory limitations prior to use. 2. Referenced Documents 2.1 ASTM Standards: C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials D92 Test Method for Flash and Fire Pointsby Cleveland Open Cup Tester D140 Practice for Sampling Bituminous Materials D3461 Test Method for Softening Point of Asphalt and Pitch (Mettler Cup-and-Ball Method) E1 Specification for ASTM Liquid-in-Glass Thermometers 3. Summary of Test Method 3.1 Two horizontal disks of bitumen, cast in shouldered brass rings, are heated at a controlled rate in a liquid bath while
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each supports a steelball. The softening point is reported as the mean of the temperatures at which the two disks soften enough to allow each ball, enveloped in bitumen, to fall a distance of 25 mm [1.0 in.]. 4. Significance and Use 4.1 Bitumens are viscoelastic materials without sharply defined melting points; they gradually become softer and less viscous as the temperature rises. For this reason, softening points mustbe determined by an arbitrary and closely defined method if results are to be reproducible. 4.2 The softening point is useful in the classification of bitumens, as one element in establishing the uniformity of shipments or sources of supply, and is indicative of the tendency of the material to flow at elevated temperatures encountered in service. 5. Apparatus 5.1 Rings—Two square-shouldered brassrings conforming to the dimensions shown in Fig. 1(a). 5.2 Pouring Plate—A flat, smooth, brass plate approximately 50 by 75 mm [2 by 3 in.]. 5.3 Balls—Two steel balls, 9.5 mm [3⁄8 in.] in diameter, each having a mass of 3.50 6 0.05 g. 5.4 Ball-Centering Guides—Two brass guides for centering the steel balls, one for each ring, conforming to the general shape and dimensions shown in Fig. 1 (b). 5.5Bath—A glass vessel, capable of being heated, not less than 85 mm in inside diameter and not less than 120 mm in depth from the bottom of the flare.
NOTE 1—An 800-mL, low-form Griffin beaker of heat-resistant glass meets this requirement.

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This test method is under the jurisdiction of ASTM Committee D08 on Roofing and Waterproofing and is the direct responsibility of Subcommittee D08.03 onSurfacing and Bituminous Materials for Membrane Waterproofing and Built-up Roofing. Current edition approved May 1, 2012. Published June 2012. Originally approved in 1962. Last previous edition approved in 2009 as D36 – 09. DOI: 10.1520/D0036_D0036M-12. 2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM...