Saybolt Seconds Universal

SUs Saybolt Universal seconds USDA United States Department... 

The viscosity of the spray oil, as measured by the Saybolt test, also determines its safety on plants. Other properties being equal, oils of low viscosity ate safer to use on foHage than those of high viscosity. For dormant sprays on deciduous trees, oils with viscosities between 100 and 200 Saybolt universal seconds (SUs) at 37.8°C are considered satisfactory. A lower range is often used in colder and a higher range in warmer areas. 

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. Although traditionally of Httle importance in the evaluation of vegetable and insect waxes, viscosity is an important test for mineral and synthetic waxes. One of the most frequently used tests, ASTM D88, is used to measure the time in seconds required for a specified quantity of wax at a specified temperature to flow by gravity through an orifice of specified dimensions. This viscosity is expressed in Saybolt Universal Seconds (SUS) at the temperature of the test. The SI unit for kinematic viscosity is mm /s (=cSt). 

U = dscosity flowing temperature, Saybolt Universal Seconds (See Appendix A-12 and A-13)... 

U = viscosity at the flowing temperature, in Saybolt Universal seconds. 

In decreasing order of exactness, methods of defining viscosity include absolute (poise) viscosity kinematic viscosity in centistokes relative viscosity in Saybolt universal seconds (SUS) and SAE numbers. 

The time it takes for the measured quantity of liquid to flow through the orifice is measured with a stopwatch. The viscosity in Saybolt universal seconds (SUS) equals the elapsed time. 

The following formulas may be used to convert centis-tokes (cSt units) to approximate Saybolt universal seconds (SUS units). For SUS values between 32 and 100 ... 

For industrial gears and circulating oils there is a specification published by the American Gear Manufacturers Association, which expresses the viscosities corresponding to the AGMA Lubricant Numbers in Saybolt Universal Seconds only. The approximate viscosities in centistokes are provided in Table 52.4 for convenience. The recommendations in Tables 52.5 and 52.6 are intended as a guide for lubricant selection. 

SpGr = specific gravity of fluid, relative to water =1.0 St = dust hazard class St St = stainless steel SSU = viscosity Saybolt universal seconds °S = degrees of superheat, °F T = absolute inlet or gas temperature, degrees... 

U , = viscosity at flowing temperature, Saybolt universal seconds... 

NOTE The 50-HB designation refers to an alcohol-started polymer containing equal parts by weight of POP and POE. The 5100 designation equals the viscosity in Saybolt Universal Seconds at 38 °F (100 °F). This product is water-soluble only below 40 °C. 

In the SI system, the theoretical unit of v is m2/s or the commonly used Stoke (St) where 1 St = 0.0001 m2/s = 100 cSt = 100 centiStoke. Similarly, 1 centiStoke = 1 cSt = 0.000001 m2/s = 0.01 Stoke = 0.01 st. The specific gravity of water at 20.2°C (68.4°F) is almost 1. The kinematic viscosity of water at 20.2°C (68.4°F) is for all practical purposes equal to 1 cSt. For a liquid, the kinematic viscosity will decrease with higher temperature. For a gas, the kinematic viscosity will increase with higher temperature. Another commonly used kinematic viscosity unit is Saybolt universal seconds (SUS), which is the efflux time required for 60 mL of petroleum product to flow through the calibrated orifice of a Saybolt universal viscometer, as described by ASTM-D88. Therefore, the relationship between dynamic viscosity and kinematic viscosity can be expressed as... 

Saybolt Universal Seconds (SUS) are used to measure viscosity. The efflux time is the SUS required for 60 mL of a petroleum product to flow through the calibrated orifice of a Saybolt Universal viscometer, under carefully controlled temperature and as prescribed by test method ASTM D 88. This method has largely been replaced by the kinematic viscosity method. SUS is also called the SSU number (Seconds Saybolt Universal) or SSF number (Saybolt Seconds Furol). 

Saybolt Universal Seconds (SUS), Degree Engler, and Seconds Redwood are applicable to fluids with centistokes greater than 50. 

Sauter mean diameter, 11 795, 13 135, 23 186, 188, 189, 190-191 Sauter mean drop diameter, 10 755, 756 Savannah River production reactors, 17 583 Savard/Lee gas-shielded tuyere, 16 151 Savard-Lee injectors, 14 741 Savory, 23 171 Saybolt color scale, 7 310 Saybolt Universal Seconds (SUS), 15 207 Saytex HP-7010, 11 474 S-B-S block copolymers, 24 706 S-B-S polymers, 24 713-714, 715 SC9... 

Saybolt Universal viscosity the time, in seconds (Saybolt Universal seconds, SUS), for 60 mL of fluid to flow through a capillary tube in... 

Butene Polymer Dynamite A cohesive, nonsifting Dynamite was prepd from NG 6, AN 80.4, NaN03 5, woodpuip 2, fine apricot-pit pulp 4.1, yel com flour 1.5, chalk 0.5 0.5% of a soln contg 7.5% polybutene(solid rubber of mw 80,000) in liq polybutene(viscosity 154 Saybolt Universal seconds at 210°FXRef). Other formulations of powdery cohesive Dynamites are also given... 

SSU, SUS (Saybolt Universal seconds)—see Saybolt Universal viscosity. 

Kinematic, cs Saybolt Universal Seconds ASTM distillation, 0 F ... 

Saybolt Second Universal or Saybolt Universal Second viscosity measure. The time (in seconds) for 60 ml of fluid to flow through a Saybolt Universal Viscosimeter at 40°C to 100°C. Crankcase or oil reservoir of an internal combustion engine. Boundary between two phases. The term surface and interface are often used interchangeably. 

In the test, the time for a fixed volume of liquid to flow under gravity through the capillary of a calibrated viscometer under a reproducible driving head and at a closely controlled temperature is measured in seconds. The kinematic viscosity is the product of the measured flow time and the calibration constant of the viscometer. Conversion of the kinematic viscosity in centistokes (cSt) at any temperature to Saybolt Universal viscosity in Saybolt Universal seconds (SUS) at the same temperature and for converting kinematic viscosity in centistokes at 122 and 210°F to Saybolt Furol viscosity in Saybolt Furol seconds (SFS) at the same temperatures (ASTM D-2161) is avaibale through formulae. 

The viscosity of a fluid is a measure of its resistance to flow and is expressed as Saybolt Universal seconds (SUS), Saybolt Furol seconds (SFS), or cen-tistokes (cSt, kinematic viscosity). Viscosity is one of the more important... 

Kinematic viscosity is measured by timing the flow of a fixed volume of material through a calibrated capillary at a selected temperature (ASTM D-445, IP 71). The unit of kinematic viscosity is the stokes, and kinematic viscosities of waxes are usually reported in centistokes. Saybolt Universal seconds can be derived from centistokes (ASTM D-2161) ... 

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