The program also converts specific gravity to API gravity and vice versa, viscosity from centipoises, SSU and SSF to centistokes. It calculates the specific gravity and viscosity of blended petroleum products and the compressibility factor at a specified temperature and API gravity.

LIQPROP® is a software program for calculating the specific gravity, viscosity, bulk modulus and compressibility factors of petroleum products at various temperatures and pressures.


Here is a sampling of LIQPROP’s features:

  • Create a database of liquid properties. Gravities, viscosities and temperatures can be input in a spreadsheet and saved for later use. As new product information becomes available, the database can be updated. LIQPROP uses this database to calculate the blended properties of a mixture of different liquids. In the individual data entry screens, default data pulled from the database can be overridden by entering new data.
  • Calculates specific gravity or API gravity, given one or the other.
  • Calculates or converts from one set of viscosity units into another, such as SSU, SSF, centipoises or centistokes.
  • Given two values of specific gravities at two different temperatures, the specific gravity at a third temperature can be calculated.
  • Given two values of viscosities at two different temperatures, the viscosity at a third temperature can be calculated.
  • For a mixture of up to ten different products, the specific gravity of the blended composition can be calculated for given percentage of each product.
  • For a mixture of up to ten different products, the viscosity of the blended composition can be calculated for given percentage of each product.
  • The Isothermal and Adiabatic Bulk Modulus of petroleum products can be calculated for given API gravity, pressure and temperature.
  • The compressibility factor using the API method, can be calculated for petroleum products, for specified values of API gravity and temperature.
  • LIQPROP can be run on Intel Pentium or AMD Athlon based computers and a minimum 64 MB RAM running Microsoft Windows 2000/XP and Windows Vista.

Technical Support:

Technical support is provided for licensed users of the software for a period of sixty(60) days from the initial purchase date. The software Registration form must be returned to SYSTEK to be eligible for Technical Support. Economical Annual Technical Support plans are available after the initial 60-day period. Minor upgrades and maintenance releases are posted at SYSTEK’s Web site for licensed users to download free of charge. You may need to contact SYSTEK to obtain a password for downloading and installing an upgrade from the web site. Major upgrades are issued twice a year at special prices to current licensed users. Call or write for details of Technical Support plans.


You may purchase or lease LIQPROP software. The minimum lease period is two months. Multi-user licenses are also available. The software is available for purchase or lease via direct download from our web site as well as via CD-ROM shipped to you in the mail. Registration is via the internet. A single user license may be installed on multiple machines and registered via the internet. However, only one copy may be executed at any time on one computer.