Applications 
State-of-the-art Measurement Accuracy is Vital to Control the Volumes and Money Involved when Transferring Oil Products 

Custody transfer operations require rational and automated handling where the measuring equipment must ensure the highest possible accuracy combined with minimal service requirements. The high-accuracy level gauge (± 0.5 mm instrument accuracy) is, together with the temperature sensors, approved for legal custody transfer according to:

  • OIML, International Organization of Legal Metrology (OIML R85:1998, or R85:2008)
  • ISO, International Organization of Standards (ISO 4266, part 1-6)
  • API, American Petroleum Institute (API ch 3.1B, ch 3.3, ch 3.6 and ch 3.7)
  • Several national certifying organizations / institutes

A custody transfer certificate is carried out by a reliable test / metrological institute, to guarantee the installed system performance. It must be possible to seal vital parts of the instrument and subsequent verification of measurements is also necessary.

"We wanted custody transfer accuracy. So we didn’t need to think twice."

   

Dieter Gerstenkorn is Technical Manager of MUT (Magdeburger Umschlag und Tanklager KB), one of Germany’s most modern tank terminals that turns over more than 6,500 cubic meters of fuel and diesel oil per day. The oil products from major oil companies like BP and Shell arrive by tanker barge and train. Before onward transport by tanker truck the oil is pumped over one of the terminal’s 10 cisterns, which have a total capacity of 65,000 cubic meters.

Highest measurement accuracy

At MUT, 20-30 custody transfer operations are made on a daily basis. The high turnover speed in such an operation demands rational and automated handling where the measuring equipment must ensure the highest possible accuracy combined with minimal service requirements.

To approve custody transfer, PTB (the German regulatory authority) requires that the oil level in the tanks can be measured to an accuracy better than ± 2 mm. MUT selected Rosemount Tank Gauging equipment as the obvious choice.

The authorities check the accuracy of measuring equipment every other year. In additon MUT carries out an internal inspection every quarter. No corrections have been required.