ASTM D4893-20

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it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
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Designation: D4893 − 94 (Reapproved 2015) D4893 − 20
Standard Test Method for
Determination of Pitch Volatility
This standard is issued under the fixed designation D4893; 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
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—SI units formatting was corrected editorially in May 2015.
1. Scope Scope*
1.1 This test method covers the determination of the percent of pitch volatility.
1.2 Since this test method is empirical, strict adherence to the procedure is necessary.
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are given for information only.
1.3.1 Exceptions—The diameter of a special aluminum block is measured in inches.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 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.
2. Referenced Documents
2.1 ASTM Standards:
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
3. Summary of Test Method
3.1 An aluminum weighing dish with about 15 g of specimen is introduced into the cavity of a metal block heated and
maintained at 350 °C (662 °F). After 30 min 6 10 s during which the volatiles are swept away from the surface of the liquid pitch
by preheated nitrogen, the sample is taken out and allowed to cool down in the desiccator. The pitch volatility is determined by
the sample weight loss and reported as percent weight loss.
4. Significance and Use
4.1 This test is useful in evaluating and characterizing pitch physical properties in comparing the consistency of shipments and
sources of supply.
5. Apparatus
5.1 Aluminum Block, 4 ⁄2 in. outside diameter, composed of two sections (Figs. 1-4).
5.1.1 The top block is maintained at a chosen constant temperature according to the signal from the thermocouple inserted into
the thermowell No. 1 near the center of the block. A proportional temperature controller regulates the heat input. Two insulated
handles are attached to this part for easy handling. An additional thermowell No. 2, located in the center of the block,
accommodates another thermocouple used only for the determination of the rate of temperature rise of the pitch. When the screw
at the bottom of the No. 2 well is taken out, the thermocouple can then be pushed down and inserted in pitch.
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.
Current edition approved April 1, 2015June 1, 2020. Published May 2015June 2020. Originally approved in 1989. Last previous edition approved in 20092015 as
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D4893 – 94 (2009).(2015) . DOI: 10.1520/D4893-94R15E01.10.1520/D4893-20.
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 Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
An aluminum block that may be obtained on special order from Koppers Company, Inc., 1005 Wm. Pitt Way, Pittsburgh, PA 15238, has been found satisfactory for this
purpose; or drawings of block will be furnished by Koppers upon request. If you are aware of alternative suppliers, please provide this information to ASTM International
Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4893 − 20
FIG. 1 Schematic of the Volatility Apparatus
5.1.2 The bottom block has a cavity for the aluminum weighing dish. A spiral channel cut around the periphery of this part
serves for preheating the nitrogen introduced at the measured rate (10 cm /min) into the block for purging volatiles.
5.1.3 The test temperature, the same as that in the top block, is maintained by the second proportional temperature controller
according to the signals of a thermocouple inserted in a thermowell No. 3 of the bottom block. There is a hole in the center of the
bottom cylinder to accommodate the sample platform, a rod with a stainless steel disk welded to its top. The aluminum sample
dish containing the sample rests on top of this disk during the test. The aluminum sample dish can be lifted out of the cavity by
raising the disk up to the upper rim of the cavity.
5.2 Aluminum Weighing Dish.
3 3
5.3 Flowmeter, 0 cm /min to 25 cm /min range.
5.4 Nitrogen Cylinder, equipped with a pressure regulator.
5.5 Timer, with an alarm.
5.6 Aluminum Plate, 127 mm by 127 mm, approximately 20-gauge.
5.7 Sieves—U.S. Standard 4.75 mm (No. 4) conforming to Specification E11.
6. Dehydration of Sample
6.1 Hard Pitch—If the solid bulk sample contains free water, air-dry a representative portion in a forced-draft oven at 50 °C
(122 °F).
D4893 − 20
FIG. 2 Internal Schematic Lower Block
6.2 Soft Pitch (Softening Point <60 °C (<140 °F))—If the presence of water is indicated by surface foam on heating, maintain
a representative portion of the bulk sample at a temperature between 125 °C and 150 °C (251 °F and 302 °F) in an open container
until the surface is free of foam. Take care not to overheat, and remove heat source immediately when foam subsides.
7. Preparation of Working Sample
7.1 Crush sample to pass No. 4 mesh (4760 μm).(4.75 mm).
8. Preparation of Apparatus
8.1 Assemble the apparatus so that the exit opening in the upper block is aligned w
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