This appendix contains the following topics:
The following procedures illustrate how the system calculates standard volume.
Calculating Standard Volume from Ambient Volume
Calculating Standard Volume from Weight
Use the following American Society for Testing and Materials (ASTM) Tables for ambient to standard conversions:
Relative Density (where gallons or imperial gallons are used) - use tables 23B and 24B
Absolute Density (where metric volume measure are used) - use tables 53B and 54B or 53D and 54D
API Gravity - use tables 5B and 6B
To calculate when Branch Base Temperature Equals Table Temperature
Use the following procedure when Branch Base Temperature equals Table Temperature (60F or 15C).
The following four factors must be available:
Ambient/Observed Volume
Temperature of the product in the tank
Density
Density Temperature
Complete the following steps:
Use the ASTM tables to locate the Corrected Density.
Find the intersection of Density along the horizontal axis and Density Temperature along the vertical axis.
Use the second in the pair of ASTM tables to locate the Volume Conversion Factor (VCF).
Find the intersection of Corrected Density along the horizontal axis and Temperature along the vertical axis.
Multiply the VCF by the ambient Quantity to arrive at the Standard Quantity.
To calculate when Branch Base Temperature Does Not Equal Table Temperature
Use the following procedure when Branch Base Temperature differs from ASTM Table Temperature.
Complete the following steps:
Use the ASTM tables to locate the Corrected Density.
Find the intersection of Density along the horizontal axis and Density Temperature along the vertical axis.
Use the second in the pair of ASTM tables to locate the Volume Conversion Factor (VCF).
Find the intersection of Corrected Density along the horizontal axis and Temperature along the vertical axis.
Use the second in the pair of ASTM tables to locate a second VCF.
Find the intersection of the Base Temperature specified on Branch/Plant Constants - Page 3 and the Corrected Density from Step 1.
Divide the first VCF by the second VCF.
Multiply the VCF from step 4 by the ambient quantity to get the standard quantity.
The system uses the following formulas for calculating volume from weight readings:
Reading | Formula |
---|---|
Weight in a vacuum | Corrected Density x Standard Volume |
Weight in air | Standard Volume x (1.0001506 x Density x .0012202) |