OneSubsea PhaseWatcher Subsea Multiphase and Wet Gas Flow Meter with Vx TechnologyYour choice for well testing, production monitoring and fiscal allocation

PhaSeWaTcher SubSea MulTiPhaSe and WeT GaS FlOW MeTer WiTh Vx TechnOlOGY

The OneSubsea™ PhaseWatcher Subsea Multiphase and Wet Gas Flow Meter with Vx Technology is a production management tool, ideal for offshore and subsea applications. it can be applied to well testing, production monitoring and fiscal allocation.

The PhaseWatcher multiphase flow meter (MPFM) and wet gas flow meter (WGFM) provides a unique solution to perform real-time process measurement at the well or at a manifold commingled process stream for subsea installations. The flow meter is a robust measurement tool that operates on physical metering principles. it is a substitute for conventional separator system, offering a more flexible and cost-effective solution.

1

WhY MulTiPhaSe and WeT GaS FlOW MeTerinG?

Multiphase and wet gas flow metering is ideal for

measuring wellstreams upstream of separation or for

commingling of the wellstreams. Vx technology is an

attractive alternative since it enables measurement of

unseparated wellstreams close to the wellhead. The flow

meter provides continuous monitoring of well performance,

thereby leading to better reservoir exploitation.

The OneSubsea PhaseWatcher flow meter reduces well

testing times while lowering operational costs.

Benefits:

• Continuous, accurate well monitoring

• Space and weight savings

• Increased well testing efficiency

• No deferred production during testing

• Improved well diagnostics with

higher-resolution data

• Improved accuracy compared to the

separators

• Immediate detection of water or gas

breakthrough

• Increased safety with high-pressure

equipment and real-time monitoring

of pressure and temperature

• Extended or increased production

from low-pressure wells due to

increased availability of the test

separator for production purposes

• Improved recovery rate due to

continuous well monitoring

• Remote operation and real-time

support, in conjunction with the

OneSubsea FRIEND® Remote

Surveillance and Diagnostic System

• Highly accurate measurement for

reservoir management and improved

reservoir recovery factor

• Accurately allocated production from

each well, field or reservoir

• Critical information provided to flow

assurance engineers and pipe integrity

management

2

WhY OneSubSea PhaSeWaTcher?

The OneSubsea PhaseWatcher flow meter with Vx

technology lets you measure oil, gas and water flow rates

without prior separation. Among the most compact flow

meter systems on the market, the OneSubsea PhaseWatcher

flow meter has no moving parts, making it essentially

maintenance-free.

features:

• Fully qualified and field-proven

technology; TRL-7

• Capable of measuring from 0% to

100% gas volume fraction (GVF),

utilizing a unique fluid mechanics

model, embedded in one software

system in the same hardware package

• Continuous physical measurement

of fractions down to atomic level,

and is not affected by foam; emulsion

fluid production; or the oil, water or

gas phases

• Completely independent of

flow regime, such as slug flow, by full

data processing of the flow rate at

high frequency

• Erosion-resistant design – Venturi

with Blind-T upstream and no sensor

in direct contact with the fluid

• One of the most compact flow meters

on the market

• Continuous measurement for all

phases independent of transition from

oil to water or gas continuous flow,

from low to high API, and from low

to high viscosity

• Exposed to more than 10,000

well tests per year with continued

feedback for R&D (fluid knowledge

and technology)

3

hOW The OneSubSea PhaSeWaTcher WOrkS

Physical PrinciPle

Measuring at the atomic level, the OneSubsea

PhaseWatcher flow meter requires no process control,

meaning that any changes in flow regime and fraction

holdups are measured, not avoided. The flow meter

performs this measurement 45 times per second using

the fastest gamma detector on the market. Most gamma

detectors operate at 1/4 of the speed, preventing them

from resolving these fast changes in intermittent flow

regime or holdup as quickly or accurately.

The well test data obtained are considered highly reliable

and help diagnose production anomalies continuously;

they can resolve challenges more quickly and can help

produce the wells more efficiently. The OneSubsea

PhaseWatcher flow meter also is used to provide accurate

flow rates during well cleanup operations. It also can

improve flow assurance and well performance, and can

reduce operating times. This increased efficiency results

in lower operational costs.

roBust fraction MeasureMent

The SMART Detector developed for the Vx technology

is produced in a unique center of excellence at the

Schlumberger Princeton Technology Center, where all

nuclear detectors are developed for all of Schlumberger’s

downhole tools. It also has provided detectors for some

of NASA’s space missions. This world-class sensor,

with an accuracy better than 0.01 on a yearly basis, is

available exclusively for Schlumberger and OneSubsea

products. One of the main benefits of the SMART

Detector when used in the PhaseWatcher flow meter is its

ability to compensate and maintain a constant accuracy

independent of the fluid process temperature, providing a

highly reliable input to the measurement system.

froM 0% to 100% GVf

The OneSubsea PhaseWatcher flow meter offers the

added value of being able to measure the process fluid

throughout the entire life of the field and the changing

process regimes, from heavy oil (multiphase) to gas

condensate (wet gas). It is the only meter with a field-

proven (TRL 7) capability of measuring from 0% to

100% GVF, making it both an MPFM and a WGFM

in one single hardware platform. The OneSubsea

PhaseWatcher flow meter has been independently tested

for all process regimes.

The only subsea multiphase meter with field-proven capability to measure from 0% to 100% GVF with the exact same technology.

0% 50% 100% GVf

oil Wells Wet Gas Wells

4

reMote seal systeM

The OneSubsea PhaseWatcher flow meter uses a unique

and innovative remote seal system on the differential

pressure transmitter, comprising two remote seal

membranes fitted directly onto the Venturi body and

specifically developed for multiphase applications.

The remote seal system reduces the likelihood of any

hydrocarbons or water entrainment in the capillary

tubing, which can cause wax clogging or hydrate

formation and, consequently, malfunction.

third-Party floWlooP Validation

The PhaseWatcher flow meter has been evaluated by

several operators in flow loops and field trials, including

National Engineering Laboratory’s (NEL’s) Joint

Industry Projects (JIPs), the Multiphase II JIP for oil

applications and the Wet Gas JIP at CEESI. The flow

meter also has won comparative independent tests

performed in third-party flow loops.

High-viscosity testing at NEL proved that the

PhaseWatcher flow meter outperformed the competition.

It was subsequently selected for the challenging

application and has been performing to specifications.

fiscal allocation

Several fields rely on the PhaseWatcher flow meter for

fiscal allocation between different licensed fields. The

first fiscal allocation application for the PhaseWatcher

was installed in 2000, allowing the customer to allocate

their production before commingling. In 2009, the

PhaseWatcher flow meter was selected as the first

worldwide, cross-border fiscal allocation measurement

system between Norway and Denmark.

NEL Test Facility in Glasgow, UK Third-party Test Loop Facility in Trondheim, Norway

5

Vx TechnOlOGY

inPut ParaMeters

There are five parameters collected by the PhaseWatcher

flow meter: temperature, pressure, differential pressure

and a multienergy gamma fraction measurement – a 32

keV with an attenuation mechanism of photoelectric

absorption, an 81 keV with an attenuation mechanism

of mostly Compton scattering with a small photoelectric

absorption effect and a 356 keV with an attenuation

mechanism of only Compton scattering.

• Temperature and pressure are used to calculate

standard conditions values using PVT.

• Differential pressure (DP) is used to calculate

the total mass flow.

• Nuclear count rates are used to determine the holdup

of oil, water and gas in the meter.

The multienergy gamma fraction measurement provides

oil, water and gas holdups that are used to determine

the fractions of each phase. When the fractions are

known, the Venturi meter is used to measure the total

mass flow rate before the individual phase flow rates

can be calculated.

The OneSubsea PhaseWatcher flow meter with Vx technology is based on fundamental physical principles: determine the total mass or volumetric flow by means of a Venturi using the improved bernoulli equation. The fluid density, gas-liquid and water-liquid ratios are determined by means of gamma measurement techniques.

1. Venturi body

2. SMarT Gamma detector

3. instrumentation housings – P, T & dP

4. Power & communication Pod

5. interconnecting hose harness

6. electrical connectors to control System

6

6

3

3

4

5

1

2

6

sMart detector

The multienergy gamma measurement uses a single

Barium-133 gamma ray source, which emits photons at

several energy levels. A SMART Detector located on the

opposite side of the venturi throat detects the gamma

photons that have not been absorbed by the mixture.

A photomultiplier in the SMART Detector converts the

gamma photons into electric signals that are digitally

processed with more than one million operations per

second. It records not only the number of photons,

but also the energy level of each photon, building up

the energy spectrum given by the gamma ray source.

The Barium-133 source was selected because it has a

significant natural peak of energy within specific bands.

The Smart Detector technology has been specifically

adapted from nuclear measurements developed for

wireline and well logging tools where high-speed

processing is required.

The attenuation of the gamma photons by the fluid

are measured at three different energy levels (32, 81

and 356 keV). Two energy levels are used in the direct

measurement (32 and 81 keV), while the third is used for

additional measurements and diagnostic purposes. The

attenuated gamma photons and fluid properties are the

basis for the oil, water and gas fraction determination.

From this, a variety of parameters can be extracted,

including fluid fractions (liquid, gas, oil and water),

water-liquid ratio (WLR) and mixture density.

The success in the development of the nuclear

measurement is not only density, but also atomic

composition dependent on the analysis of the gas, water

and oil. This allows the fraction meter to work even if

there is no density contrast due to the atomic composition

of the oil and water being different (H2O+NaCl versus

CnHm). The technology has been used even with 8 API,

which means density higher than the water with the same

level of accuracy.

solution trianGle

The principle of the gamma measurement system can be

visually illustrated as a triangle. For each phase, the ratio

of high-energy count rates is plotted against the ratio of

low-energy count rates on an x-y chart. 100% of each

phase become the apexes of the solution triangle. Any

combination of high- and low-energy count rates resulting

from measurements of hydrocarbons and the water

mixture will fall within this triangle.

= Operating Point = GVF 50%, WLR 50%

Low Energy Attenuation (32 keV)

High E

nergy Attenuation (81 keV

)

Water

Gas

oilConsta

nt WLR Line (

50%)Constant GVF Line (50%)

A visual interpretation of the solution triangle is presented in the diagram, where the triangle corner points are the single-phase attenuations. An operating point example is shown at 50% GVF and 50% WLR. The constant GVF line is parallel to the water-oil line, and the constant WLR line intersects the gas point.

7

cOMMunicaTiOn inTerFaceS

in the OneSubsea PhaseWatcher flow meter with Vx technology, all data processing is performed in the flow meter. it interfaces with any standard communication protocol and requires low power, in compliance with all industry-standard subsea control systems.

data acquisition floW coMPuter

The Data Acquisition Flow Computer (DAFC) is

the heart of the PhaseWatcher flow meter. It interfaces

with the sensors and computes the flow rates. Based on

preloaded PVT data, the DAFC converts flow rates from

line to standard conditions. DAFCs have several physical

communication interfaces: two serial port interfaces,

one USB and one Ethernet port (plus one optional

Ethernet port).

coMMunication Protocols

The PhaseWatcher flow meter with Vx technology is

easy to interface and complies with industry standards.

Software has been developed to comply with both

IWIS and SIIS Level 2 standards. The presence of the

Ethernet complies with SIIS Level 3. Client-specific

requirements are addressed by highly qualified

in-house software engineers.

data aVailaBility

To fully utilize the flow meter’s capabilities, it is

strongly recommended to have high-speed data transfer

(38,400 baud) to each meter to enable retrieval of

raw measurements. This will enable detailed flow

assurance diagnostics and capability to post process

meter measurements with new fluid properties or

PVT information, and also allows the use of remote

surveillance expertise via the FRIEND system.

Bandwidth as low as 1200 baud has been achieved,

but reduces the capacity of the use of the entire

diagnostic tool.

Vx serVer

OneSubsea can supply a Vx server, which is the diagnostic

interface to the PhaseWatcher flow meter. The Vx server’s

industrial specified hardware is selected from the best

components in the market to ensure a reliable platform

for real-time applications.

The Vx server’s diagnostic interface to the OneSubsea

PhaseWatcher flow meter can be used locally or remotely

to interrogate the status of the flow meter. It also can be

connected to OneSubsea’s FRIEND system for remote

assistance and surveillance.

Vx GateWay

The optional Vx Gateway software enables a control

system to interface PhaseWatcher flow meters through an

OPC interface with a client-selected set of Modbus RTU

registers. The Vx Gateway software can interface up to 16

meters simultaneously and can provide real-time logging,

which is useful for analysis and trending.

coMMunication standard interface Protocol PoWer consuMPtion

Serial EIA (RS) 485 Two wireModbus RTU TCP over Modbus (Tunneling)

24 W

Serial EIA (RS) 422 Four wireModbus RTU PPP, TCP over Modbus (Tunneling)

24 W

Ethernet

Copper modem Modbus TCP, Boot P

24 WFiber-optic modem OPC (Vx Gateway)

CAN modem SIIS Level 3

CAN Two wire CAN open, SIIS Level 2 28 W

8

features:

• Fullyretrievable

• Smallandlightweight

comparable to the

control pods

• Lowpowerrequirement

• Non-intrusivedesign

• Designedforintegration

with all major subsea

control systems

•Alsopossibleto

retrieve only the

electronics, reducing the

intervention equipment

OneSubSea PhaSeWaTcher FlOW MeTer

OneSubsea offers several different compact configurations for the PhaseWatcher flow meter to meet subsea infrastructure requirements. Featuring Vx technology, the flow meter can be used for continuous monitoring of each individual well or installed in a test header for alternate well testing.

The subsea PhaseWatcher flow meter comes in a range

of sizes based on the Vx technology. As with the topside

flow meter, the size of the subsea version is determined

using the Schlumberger Vx Advisor software.

sizes: 29 mm (2” pipe ID), 52 mm (4” pipe ID),

65 mm (5” pipe ID) and 88 mm (7” pipe ID)

interVention toolinG

If the PhaseWatcher flow meter’s retrievable configuration

requires intervention, a diver can be used for shallow-

water installations. For deepwater installations, a

running tool and ROV can be used. OneSubsea offers an

intervention running tool design with the basic function

to intervene on smaller retrievable items such as insert

chokes, subsea control modules and raw seawater filters.

This tool also is used for installation and retrieval of

the PhaseWatcher flow meter. Although our customers

may prefer other methods of intervention, OneSubsea

provides this method as an option.

9

STandard cOnFiGuraTiOnS

in-line confiGuration

The in-line configuration is the base configuration

of the PhaseWatcher subsea flow meter with Vx

technology, where only the metering section is

integrated in the infrastructure using standard

interface flanges. This configuration normally is

installed on a subsea tree as part of a retrievable

choke bridge or flow control module and is not

independently retrievable.

Both the in-line and dual-hub configurations are

supplied either as an E-Type or F-Type flow meter.

The E-Type configuration is limited to a design

pressure rating to 10,000 psi (690 bar) and 212º F

(100º C), and the F-Type configuration is qualified

to a design pressure to 15,000 psi (1035 bar) and

401º F (205º C).

dual-huB confiGuration

The dual-hub configuration is a fully retrievable

version of the subsea PhaseWatcher flow meter.

Compared to the in-line design, this configuration

has integrated piping upstream of the Venturi

section, making it possible to fully retrieve the

unit from the subsea infrastructure. The dual-hub

version can be configured with a clamp set for ROV

operation during installation/removal in deeper

waters, or it can be configured with a removable

clamp set for diver installation in shallow water.

In-line E-Type

In-line F-Type

Dual-hub E-Type

Dual-hub F-Type

10

MulTiPhaSe SaMPlinG FOr SubSea aPPlicaTiOnS

by reducing uncertainties associated with variations in fluid behavior relationships and fluid composition versus time, the OneSubsea multiphase fluid sampling and analysis systems take samples at the seabed and provide powerful solutions for improving the understanding of the fluid behavior and maintaining the lowest uncertaintity of the flow rate measurements.

features:

• Captures representative oil, water and

gas samples

• Circulates fluid through ROV

sampling skid

• Features industry-standard components

and interfaces

• Operates at line pressure and temperature

• Integrated into the PhaseWatcher flow

meter’s Blind-T or supplied as a

standalone unit

• Can enrich one phase to provide larger

volumes as needed

• Optical detector distinguishes oil,

water and gas

• Based on best-in-class sampling practices

Integrated with PhaseWatcher Flow Meter with Vx Technology

Standalone Unit

11

SerVice and SuPPOrT

From discovery to abandonment, OneSubsea provides the resources needed to optimize the performance of our customers’ assets. With locations across the globe; an ever-growing pool of experienced industry experts; rental tooling to meet all installation, commissioning and workover needs; and proactive real-time operational and technical support, OneSubsea is committed to enhancing the full life performance of subsea fields worldwide.

our serVices coVer

the full life cycle of

a field, includinG:

• Installationand

Commissioning

• LifeofField

• AssetManagement

12

friend reMote surVeillance

and diaGnostic systeM

FRIEND is OneSubsea’s online support and

condition monitoring system. A real-time historian

database makes it possible to conduct event-driven

data collection and trending of historical data.

Additionally, the FRIEND system’s automated

alert feature continuously monitors system

performance for abnormal process or system

conditions and alerts OneSubsea personnel on

duty. This information enables OneSubsea to

provide a proactive service through an integrated

working methodology with customers, securing

best practices in operation and maintenance of the

products and systems. This expertise is available

remotely and allows additional processing for a

fourth phase, such as burst sand detection, scale

deposition, etc.

friend systeM serVices include:

• 24/7 online helpdesk and access to our technical

experts on duty

• Online access to real-time data at field startup

and throughout the product life (equipment

signature/footprint)

• Condition- and campaign-based maintenance

invoked by condition monitoring

• Online access to interactive engineering

applications for equipment operational assistance

• Interpretation and evaluation of field data and

optimized equipment utilization

• Periodic validation of the Vx technology’s

performance, including reference and PVT data

• Assistance with production testing activities

• Daily, weekly or monthly reports; can be

accessed via an online portal

• Online access to project document repository

and equipment management

13

4646 W. Sam houston Pkwy. n.

houston, TX 77041

uSa

Tel 1 713 939 2211

5 Mondial Way

harlington

hayes, ub3 5ar

england, uk

Tel 44 208 990 1800

Sandslikroken 140

PO box 174

Sandsli, n-5862

bergen, norway

Tel 47 55 92 88 00

level 11, 12-14

The esplanade

Perth, Western australia

6000

Tel 61 8 6389 5000

www.onesubsea.com

©2013 cameron | Friend is a registered trademark of OneSubsea. OneSubsea is a trademark of OneSubsea. | Sb 1M 05/13 ad00682OSS