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Custody Transfer 101 Theory and Application

Presentation to the GASNZ Industry Forum

November 2017

Innovative Gas Measurement Solutions

p.baldwin@nzmeter.co.nz

Innovative Gas Measurement Solutions

p.baldwin@nzmeter.co.nz

DE-REGULATED

ENERGY MARKET

NZS 5259 SPECIFICATIONS

0 20 40 60 80 100

Capacity (% Qmax)

0

1

2

-1

-2 Err

or

Of

Ind

ica

tio

n (

%)

atm. air

Qmin / Qt : 0.05 Qmax / 0.2 Qmax

ACCURACY : +/- 1% ( Qt - Qmax ) / +/- 2% ( Qmin - Qt )

REPEATABILITY : 0.1% Span ( Qt - Qmax )

17,520,000 . Nm 3

G160 (250 m³/h) AT 1 bar OPERATING PRESSURE SHOWS AFTER 16 YEARS:

CONSEQUENCE OF 1% ERROR AT A YEARLY

GAS CONSUMPTION OF 25% Qmax

G-VALUE PRESSURE

0,02 bar

PRESSURE

1 bar

PRESSURE

4 bar

PRESSURE

8 bar

G65 (100 m³/h) 2200 4400 11000 20000

G100 (160 m³/h) 3600 7000 18000 32000

G160 (250 m³/h) 5700 11000 28000 51000

G250 (400 m³/h) 9200 18000 45000 81000

G400 (650 m³/h) 15000 29000 72000 130000

ERROR EXPRESSED IN Nm

AFTER 1 YEAR IN OPERATION

Turn Down Ratio

Monday

morning in the

winter Qmax

Turn Down Ratio

Summer

evening

Qmin

Turn Down Ratio

0 25 50 75 100

0

200

400

600

800

1000 TIME (CUMULATIVE)

INDUSTRIAL CONSUMER

0 25 50 75 100

CAPACITY (%Qmax)

0

2

-2

-4

-6

-8

-10

ERROR OF INDICATION (%)

TURNDOWN RATIO 20:1

TURNDOWN RATIO 10:1

0 25 50 75 100

CAPACITY (% Qmax)

0

200

400

600

800

1000TIME (CUMULATIVE)

FREQUENCY DISTRIBUTION INDUSTRIAL CONSUMER 2000

FREQUENCY DISTRIBUTION INDUSTRIAL CONSUMER 2005

Turn Down Ratio

Ultrasonic Gas Flow Meter

Ultrasonic Meter Principle

Multiple Paths

Qsonic 5

TURBINE GAS METERS

TURBINE WHEEL

BODY

FLOW CONDITIONERS

INDEX

OPERATING PRINCIPLE

GUIDING VANES

0 25 50 75 100 125

Capacity (%Qmax)

0

0.5

1

-0.5

-1

Error of indication (%)

air, atmospheric natural gas, 1bar

natural gas, 2bar natural gas, 4bar

Pressure effect (optimized turbine meter)

G400

G650

G1000

CARTRIDGE

IDENTICAL BEARING BLOCKS

OPTIMIZED BLADES = OPTIMIZING VELOCITY

ROTARY METER

G6 (1 1/2”) – G650 (6”)

How a rotary meter measures:

Domestic Diaphragm Meter

Electronic Volume Corrector

Questions ?

p.baldwin@nzmeter.co.nz

Innovative gas measurement solutions

FMG Products

- ROTARY METERS

- TURBINE METERS

- EVCD / FLOW COMPUTERS

- TEST BENCHES / MASTER METERS