HERMAN HOFSTEDE Sales Director, KROHNE Oil & Gas

Started his career at the Dutch Weights and Measures (NMi) were he was involved in National Approvals of flow meters used for Liquid Custody Transfer applications. Joined the largest independent inspection company involved in training, auditing, inspecting and calibrating on-site proving facilities, most of them based on ball provers. Joined KROHNE as a Product Manager for Custody Transfer Ultrasonic flow meters and represented KROHNE in several API committees. Presently responsible for global international sales for KROHNE Oil & Gas. Experience of 35 years in Custody transfer measurement

On Site & in Situ Proving of Liquid Ultrasonic Flow Meters using Master Meter technology

•Prover tanks

•Bi-directional ball provers

•Uni-directional ball provers

•Compact provers

•Master meters

Different calibration concepts

Increase efficiency

Less Maintenance

Reduce calibration frequency

Use On-board diagnostics

Longer working life

What do you want to achieve

Proof performance compliance

Problems affecting metering

flow disturbances,

changes in flow profile within the pipeline

Changes in product

properties such as density,

composition, viscosity

Mechanical wear and tear

Quantities being

measured, the range of

flows

Who is measuring the

product

What is affecting Flow Meter performance

Specifically related to Mechanical type of flow meters

Considerations for the Master Meter calibration concept based on ultrasonic flowmeters

– No internal moving parts

– No wear or tear

– Stable geometric construction

– Fully welded – all stainless steel – construction

– Integrated diagnostics

Table deleted in API CH 5.8 2nd edition Table included in API CH 5.8 1nd edition

Using a ball prover for calibrating ultrasonic flow meters

Runs Repeatability

Band % (R)

Uncert.

%

3 0,02 0,027

4 0,03 0,027

5 0,05 0,027

6 0,06 0,027

7 0,08 0,027

8 0,09 0,027

9 0,10 0,027

10 0,12 0,027

11 0,13 0,027

12 0,14 0,027

20 0,22 0,027

Repeatability versus uncertainty

API MPMS Ch. 5.8 2nd edition, Annex B

Using Ultrasonic Master Meters

Leading API Standards:

• API MPMS Ch. 4.5 Master Meter Provers

• 3th edition 2010 included Ultrasonic and Coriolis Master Meters

• API MPMS Ch. 4.8 Operation of Proving Systems

• 2nd edition 2013 included formula for calculating recalibration frequency

• API MPMS Ch. 5.8 Measurement of liquids by Ultrasonic Flow meters

• 2nd edition 2011 removed recommended ball prover base volumes

• API MPMS Ch. 4.8 paragraph 10.2 Master Meter Provers (reasons which have serious impact on re calibration frequency)

• Worn or faulty parts

• Damaged meter parts

• Changes in fluid characteristics

• Loss of internal material, abrasion

• Accumulation of foreign material (such as wax) build-up in the meter

• Reprogramming of electronic based maters

• Seasonal temperature changes

• API MPMS Ch. 4.8 paragraph 10.2 Master Meter Provers (reasons which have serious impact on re calibration frequency)

All related to mechanical flow meters NOT for ultrasonic flow meters

• Worn or faulty parts no moving parts

• Damaged meter parts no moving parts

• Changes in fluid characteristics Reynolds flow meter not a volume meter

• Loss of internal material, abrasion material is high quality steel SS 316

• Accumulation of foreign material (such as wax) build-up in the meter Diagnostics

• Reprogramming of electronic based maters Check sums

• Seasonal temperature changes in build temperature sensor

API MPMS Ch. 4.8 Annex B Method for determining the Frequency of Calibrating Provers

• Calculation based on following variables:

• Percent change in meter performance between two calibrations (Pf)

• Number of months (Mn) between calibrations

• Benchmark (0.06 % or less)

• Using following formula for calculating the Months to Next Calibration (MNC):

• MNC = [(Mn) x 0.06) / (Pf)]

date of calibration

Q 15-9-2005 13-8-2007 17-8-2010 31-7-2014

m3/hr Accuracy (%)

198 -0,05 -0,04

224 -0,06

257 -0,04 -0,06 -0,06

380 -0,01 -0,04 -0,05 -0,05

545 0,03 0,00 -0,02 0,01

780 0,02 0,02

870 0,02 0,02 0,01 0,03

1045 0,01 0,04 0,01 0,04

1165 0,02 0,02 0,00

avg accuracy 0,01 0,00 -0,03 -0,01

Practical recalibration results of a 10” ultrasonic flow meter

2 x 100 % of Qmax 3 x 50 % of Qmax

Master/Duty configuration

• Ultrasonic flowmeters are adopted by International and National Oil Companies

• Diagnostic capabilities are acknowledged as one the major features of ultrasonic flow meters

• Ultrasonic flowmeters are in full compliance with National and International Standards

• Ultrasonic flowmeters can be calibrated with uni- or bi- directional displacement provers inline with API recommendations

• Master Meter calibration concept is in compliance with API standards

• Re-calibration frequency for ultrasonic Master Meters can be significantly reduced compared to mechanical type of Master Meters

Conclusions

Thank you for your attention!