The VPCR (vapor pressure of crude oil) is a major safety parameter for storage, transport, and handling of crudes. Its reliable determination is of high interest in the petroleum industry, in particular for crude oils featuring a high vapor pressure.
ASTM D6377 is one of the most common standard test methods for vapor pressure testing of crude oil requiring a relatively ambiguous shaking speed with a minimum frequency of 1.5 cycles per second (c/s). Older generations of vapor pressure testers could only shake the sample with about 1.5 c/s, whereas state-of-the-art instruments like ERAVAP can use much higher shaking speeds.
Our latest application note describes the impact of the shaking speed on measuring time, pressure stability, and accuracy and gives answers to the following questions:
• How is the VPCR result affected by changes in the shaking speed?
• Is there a bias between the VPCR result and the ”true equilibrium” vapor pressure and does this depend on the shaking speed?
• Does a higher shaking speed reduce the measurement time?
• Is there an optimum shaking speed?
Download Application Note
Please download the full-version of the application note below:
Why a higher shaker speed improves the accuracy of ASTM D6377 >>