Volumetric Tank Strapping
Streamline Inspection provides comprehensive volumetric strapping services for storage tanks and vessels. These physical measurements are obtained in the field and are required to produce the capacity tables which in turn are used to calibrate your tank gauging system with an actual volume measurement.
Streamline Inspection uses the optical reference line method, optical triangulation method and the new laser scanning method to obtain the information needed to create the capacity tables.
Customer specified inputs are:
- Innage or ullage
- Level increment: feet and inches, decimal of feet, centimetres, millimetres etc.
- Volume: barrels, gallons, cubic meters etc.
- API gravity or gravity of product stored
- Delivery format
Why calibrate an above ground storage tank?
Volumetric strapping and the capacity tables which are derived from
these measurements are the most economical and accurate way of
determining the true volume of a containment system in relation to
the liquid level. The only way that any gauging system can
accurately measure the amount of product in a containment system is
to calibrate that system with accurate capacity tables. Inaccurate
or out of date tables will negate even the most accurate gauging
systems.
Accurate calibration tables are essential with today’s high commodity prices, these tables are a good way to possibly save money for a modest upfront cost.
When to calibrate or recalibrate?
It is recommended to calibrate:
- Newly built tanks or vessels after the hydro test.
- There is a change in operating conditions such as a change in temperature of specific gravity of the product.
- Major repairs are performed, such as bottom plate replacement or major repairs involving a shell plate door sheet.
- Structural changes such as deadwood configurations, and changes to the reference gauge height.
- Cases of tank settlement may also change the shape of the tank and therefore alter the capacity tables.
- It is recommended by API that recalibration take place every 15 years.
The best time to recalibrate a tank is in conjunction with an API 653 out of service inspection. The measurements can then be taken after all repairs have been completed.
What is the Laser Scan method?
Streamline Inspection has developed a proprietary software system to utilize highly accurate and comprehensive laser scan data to develop capacity tables for tanks ships and barges. This method is much more accurate than traditional methods because it uses the millions of data points from the entire tank, traditional methods use information gathered in only a few areas around the tank and up the shell.
Why Calibrate a Storage Tank Article written by Streamline Inspection as it appeared in the November 2009 issue of Tank Storage Magazine
For more information or to view a sample calibration table please contact us at (403) 454-6630, Toll Free at (877) 620-9874 or send us an email at info@streamlineinspection.com.