ASTM , viscosity tables

The values of Saybolt Universal Viscosity at 100°F and at 210°F are taken directly from the comprehensive ASTM Viscosity Table, Special Technical Publication No. 43A (1953) by permission of the publishers, American Society for Testing Materials, 1916 Race St., Philadelphia 3, Pa. 

ISO viscosity number. Table 12.1 compares typical correlations between number and weight average molecular weights with ISO numbers, AT-values and ASTM viscosity measurements. 

The VI of oil may be determined if its viscosity at any two temperatures is known. Tables based on a large number of tests are issued by the American Society for Testing and Materials (ASTM). These tables permit calculation of the VI from known viscosity. 

TABLE 5-1. ASTM Viscosity Limits for Fuel Oils... 

Low temperature filtration (qv) is a common final refining step to remove paraffin wax in order to lower the pour point of the oil (14). As an alternative to traditional filtration aided by a propane or methyl ethyl ketone solvent, catalytic hydrodewaxing cracks the wax molecules which are then removed as lower boiling products. Finished lubricating oils are then made by blending these refined stocks to the desired viscosity, followed by introducing additives needed to provide the required performance. Table 3 Usts properties of typical commercial petroleum oils. Methods for measuring these properties are available from the ASTM (10). 

A number of arbitrary viscosity units have also been used. The most common has been the Saybolt Universal second (SUs) which is simply the time in seconds required for 60 mL of oil to empty out of the cup in a Saybolt viscometer through a carefully specified opening. Detailed conversion tables appear in ASTM D2161, approximation of kinematic viscosity V in mm /s(= cSt) can be made from the relation shown in equation 8 ... 

Viscosity Glassifications. The general ISO iatemational viscosity classification system for iadustrial oils is given ia Table 4 from ASTM D2422 (American National Standard Z11.232). For high speed machines, ISO viscosity-grade 32 turbiae and hydrauHc oils are a common choice. ISO grades 68 and 100 are appHed for more load capacity ia slower speed machines where power loss and temperature rise are less of a question. 

Table 4. ASTM D2422 ISO Viscosity System for Industrial Oils...

The original Ostwald viscometer has been modified in many ways, and a number of different versions are on the market (Table 4) (21). Most are available with a wide choice of capillary diameters and therefore a number of viscosity ranges. A number of viscometers are described in ASTM D445, which also Hsts detailed recommendations on dimensions and methods of use. 

Dynamic techniques are used to determine storage and loss moduli, G and G respectively, and the loss tangent, tan 5. Some instmments are sensitive enough for the study of Hquids and can be used to measure the dynamic viscosity T 7 Measurements are made as a function of temperature, time, or frequency, and results can be used to determine transitions and chemical reactions as well as the properties noted above. Dynamic mechanical techniques for sohds can be grouped into three main areas free vibration, resonance-forced vibrations, and nonresonance-forced vibrations. Dynamic techniques have been described in detail (242,251,255,266,269—279). A number of instmments are Hsted in Table 8. Related ASTM standards are Hsted in Table 9. 

Specifications for paving asphalt cements usually include five grades differing in either viscosity or penetration level at 60 °C (Table 8) (ASTM D496). Susceptibihty of viscosity to temperature is usually controlled in asphalt cement by viscosity limits at a higher temperature such as 135 °C and a penetration or viscosity limit at a lower temperature such as 25 °C. 

Table 8. ASTM Requirements for Asphalt Cement Viscosity...

Liquid fuels for ground-based gas turbines are best defined today by ASTM Specification D2880. Table 4 Hsts the detailed requirements for five grades which cover the volatility range from naphtha to residual fuel. The grades differ primarily in basic properties related to volatility eg, distillation, flash point, and density of No. 1 GT and No. 2 GT fuels correspond to similar properties of kerosene and diesel fuel respectively. These properties are not limited for No. 0 GT fuel, which allows naphthas and wide-cut distillates. For heavier fuels. No. 3 GT and No. 4 GT, the properties that must be limited are viscosity and trace metals. 

Specifications for soHd i7j -l,4-polyisoprenes are shown in Table 5 and include analyses for volatile matter, extractables, ash, and Mooney viscosity at 100°C. Standard method ASTM D1416 includes chemical analysis methods for volatile matter, extractables, and total ash, while ASTM D1646 includes Mooney viscosity (82). The Monsanto rheometer data for vulcanizates prepared by a standard recipe may also be specified. This formulation for vulcanizate (ASTM D3403) is mixed in a Banbury mixer in two passes with all but sulfur and accelerator added in first pass ... 

Suitable conversion tables are available (ASTM D341), and each table or chart is constructed such that for any given petroleum or petroleum product, the viscosity-temperature points result in a straight line over the applicable temperature range. Thus, only two viscosity measurements need be made at temperatures far enough apart to determine a line on the appropriate chart from which the approximate viscosity at any other temperature can be read. 

Table H1.3.1 ASTM" Sizes, Viscosity Ranges, and Constants for Cannon-Fenske Type Viscometer Tubes... 

The products from these hydrotreated syncrudes lack paraffins and have low cloud points. Therefore, they are excellent cold climate No. 2D fuels, as shown in Table VI. For diesel fuel used in typical climates, the 300°F+ products have viscosities and D 86 90% points just below the ASTM minimums. To meet this specification, the initial point could be adjusted upward. 

Three commercial samples of CLA were subjected to a series of tests, which are reported in Table 5. Viscosity was measured using ASTM test D445. It was presumed that increased viscosity might be related to increased oxidation if it had occurred. Large differences in viscosity were not found. Color of the three samples is reported, but it is only a subjective statement regarding the apparent quality of the three materials. Included in the color analysis is the absorbance maximum observed for CLA dissolved in hexane (1 1000 CLA hexane) using a Cary UVA is spectrometer. The UV spectra indicated that conjugated dienes were the major source of absorption of the oil samples. 

Correlative methods have long been used as a way of dealing with the complexity of petroleum fractions. Relatively easy to measure physical properties such as density, viscosity, and refractive index (ASTM D-1218) have been correlated to hydrocarbon structure (Table 7.3) with the potential to relate refractive index data to the nature of the constituents of a petroleum product. 

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