C Conversion Routines

This appendix contains the following topics:

C.1 Calculating Standard Volume

The following procedures illustrate how the system calculates standard volume.

  • Calculating Standard Volume from Ambient Volume

  • Calculating Standard Volume from Weight

C.2 Calculating Standard Volume from Ambient Volume

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:

  1. 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.

    Description of image073.gif follows
    Description of the illustration image073.gif

  2. 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.

    Description of image074.gif follows
    Description of the illustration image074.gif

  3. 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:

  1. 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.

  2. 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.

    Description of image073.gif follows
    Description of the illustration image073.gif

  3. 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.

    Description of image075.gif follows
    Description of the illustration image075.gif

  4. Divide the first VCF by the second VCF.

  5. Multiply the VCF from step 4 by the ambient quantity to get the standard quantity.

C.3 Calculating Standard Volume from Weight

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)