Raw Asphalt temp vs viscosity

[BERGSH]

I was wondering if anyone has any information on the relationship between temperature and viscosity for raw asphalt. The asphalt I am specifically looking for is Citgo 180 Pen asphalt. I could run the tests and make my own graph. I was just hoping someone else might have already done the same information.
Thanks

 

[jmw]

The ASTM D341 equation seems to cover a lot of hydrocarbons:

log₁₀.log₁₀([ν]+0.7)= A-B.log₁₀(T+273)
where [ν] = kinematic viscosity in cSt and T is temperature in [°]C.
In the process environment this seems to work i.e within acceptable error.

You need the viscosity at two different temperatures to solve for A & B for every sample.

You can try the spreadsheet at

http://www.ViscoAnalyser.com

(follow the link on the homepage) which solves this equation at various temperatures.

This equation is the key to some effective process viscosity measurements for asphalt blending.


JMW

http://www.viscoanalyser.com

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[BERGSH]

Hey thanks for the tip. I am looking now to convert kinematic viscosity to dynamic. Does anyone have an excel equation that does this? Thanks in advance.

 

[rmw]

Do a search on electric heat tracing. Those manufactureres typically publish technical data for the fluids they are trying to promote their products for.

I think you got your answer for your viscosity question in the other thread you posted.

rmw

 

[jmw]

There is no mystery here, simply divide by the density.
Here, this link is to the Engineering toolbox. You will also find lots of calculators there.

http://www.engineeringtoolbox.com/21_412.html

More difficult to find are relationships between PEN and kinematic viscosity. There are various papers on this around but mostly proprietary. Maybe someone else can point out an internet source.
However, PEN is not the only way to grade ashphalts, sample tresting often uses cone plate laboratory viscometers which heat the sample to a reference temperature. Experience suggests that modern process measurements can be more accurate with these difficult materials (unless you resort to exceptional sample handling and use statistical methods).

JMW

http://www.viscoanalyser.com

Eng-Tips: Pro bono publico, by engineers, for engineers.

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[25362]

In line with JMW's advice, why not use the famous "Refutas" or BP Viscosity-Temperature charts based on log log (v+0.8) vs log T, where T is the absolute temperature and v is in cSt. The graph can be used for blending of bitumens, and has the ordinate axis with various kinds of viscosity units enabling their interconversion ?

Otherwise one can use ASTM D 341 charts (middle or high range) for the purpose of plotting kin. viscosities vs temperatures.