Long Term Performance of V-Cone Flow Meters

Mike Dyer Applications Engineer

New Zealand Gas Forum

Nov. 2017

Agenda • Powerco’s Pressure Control Module

• V-Cone Meter Principles of Operation

• Data Collection

• Test Facility

• Applications Test Meter

• Test Data

• Conclusions

• Wafer damage tests

• Straight run tests

Powerco Project

• Above ground pressure control

modules.

• They were not measuring flow but

wanted to verify their model.

Options

• Turbine meters offer good accuracy

but require maintenance.

• Other technologies did not fit.

• The wafer V-Cone offers 1% of rate

accuracy and very little maintenance.

• Straight run requirements are 0 to 4

Dia. up and 0 to 2 Dia. down.

Wafer V-Cone vertical up flow

Wafer V-Cone

Cone Meter Principles of

Operation High Pressure

Port

Low Pressure

Port

Flow

Equations

=Thermal Expansion Correction

=Meter Flow Coefficient

=Gas Expansion Factor (2001)

=Meter Geometric Constant

=Differential Pressure

=Fluid Density

DPKYCFQ Da 1

aF

DC

Y

1K

DP

Test Data Collection

• Customer’s were required by the EPA

to recalibrate meters.

• All of the calibrations took place at 3rd

party lab, CEESI Co. (air calibrated)

• This reduced the added uncertainty of

a second lab.

Test Facility

• Flow rates were dictated by

customers application but were

consistent for any given meter.

• Master meter Critical Flow Venturi

(CFV).

Test Facility

• Flow rate uncertainty 0.29% to 0.35%.

• Using the root sum square method

with sensitivity factors.

DPKYF

QC

a

D

1

Cd Test Error

2222

TEPEDPEQEerrorD STSPSDPSQC

EQ

EDP

EP

ET

S

= Flow Error (0.29% to 0.35%)

= DP Error (.07 to .75%)

= Pressure Error (.07%)

= Temperature Error (± 0.5 C)

= Sensitivity Factor for each

measurement (1 to .48)

uncertainty of approximately 0.4% to 0.5%. DC

Test Meter Applications

63 total calibrations, two of the 63 calibrations were identified as

outliers based on the Grubbs test and a 99.9% confidence.

Example of Test Data

7 calibrations yielded 21 data sets

Cal Year Ave Cd YBC Cd shift YBC Cd Shift YBC Cd Shift YBC Cd Shift YBC Cd Shift YBC Cd Shift

1995 0.844681 0

2001 0.849769 6 0.60% 0

2006 0.850767 11 0.72% 5 0.12%

2008 0.84994 13 0.62% 7 0.02% 2 -0.10%

2010 0.852034 15 0.87% 9 0.27% 4 0.15% 2 0.25%

2012 0.853277 17 1.02% 11 0.41% 6 0.29% 4 0.39% 2 0.15%

2013 0.859209 18 1.72% 12 1.11% 7 0.99% 5 1.09% 3 0.84% 1 0.70%

Meter A

• As DP meters wear they generate

less DP.

• We expected to see Cd values

increase over time.

DPKYF

QC

a

D

1

Cd Change vs Time

15 meters, 61 calibrations, 107 data sets

Cd vs Time by Meter

Conclusions

• Data shows cone meters have

extremely good long term

performance.

• Recalibrating not necessary, however

we did not test abrasive fluids.

• We do recommend periodic visual

inspections.

Damaged Cone

0.845

0.850

0.855

0.860

0.865

0.870

0.875

0.880

0.885

0.890

0.895

0.900

0 20000 40000 60000 80000 100000 120000 140000 160000

Flo

wm

ete

r C

f

Re

baseline no damage

heavily damaged cone

Obstruction Test Data

• 0.45 betas are very large cone and

condition flow better than a .75 beta.

• 0.45 beta test data with elbows out of

plane and half open gate valves.

• 0.75 beta with elbows out of plane.

• 0.65 beta Wafer V-Cones with

reducers.

Straight Run Data

Gate Valve Up and Down

Stream

3 dia. up and 0 dia. down

Elbows 3 dia. Upstream

2” x 4” Reducing Adapters 2” x 4” Concentric Reducers

Reducer Data

Questions?