Subsea Multiphase Meters
- FMC Technologies
(Formerly MPM High Performance Flowmeters)
Subsea multiphase meters from FMC Technologies encompasses all the unique features of the topside meter. It has a uniquely simple field configuration procedure, without the need of any subsea sampling. It has been designed and qualified for use at large water depths, at very high operating pressures and at extremely high operating temperatures.
The state-of-the-art subsea meter represents high performance in subsea flow metering. The subsea meter is designed and built with maximum reliability and redundancy in mind. The qualification program conducted was in accordance to ISO 13628-6 and as per the DnV Qualification of New Technology, RP-A203
It can be supplied as a Multiphase meter, a Wetgas meter, or as a combined Wetgas and Multiphase meter (DualMode).
• Dual Mode (multiphase & wetgas) - Meter works equally well over full GVF range and for different .. flow conditions. At slug .. flow it switches automatically between modes.
• Unparalleled Accuracy and Sensitivity - Accuracy demonstrated during quali.. cation testing approaching the level of single phase metering, on accumulated (allocation) basis.
• Remote Access and Operation - Internet access to Graphical User Interface and full functionality via web-interface in MPM .. flow computer at site.
• Easy Field Configuration - Meter is factory calibrated. The user friendly field configuration can even be fully completed at factory prior to delivery.
• Water Salinity Measurement - Eliminates the need for water sampling. Automatic update of water configuration data and elimination of potential errors caused by incorrect input data.
• Self Diagnostics Functionality - Meter includes a large series of self diagnostics features. These are based on raw data analysis, redundancy and statistical analyses.
• In-Situ Verification - Responding to the obvious question: Are meter readings correct? Covers sensor parts as well as configuration data.
• HP/HT Qualified - Mechanical integrity verified for pressures of up to 1000 bar (15,000 psi) and temperatures of up to 250°C (480°F). Statement of Compliance issued by DNV.
The MPM subsea meters can be equipped with all of the special features offered by MPM.
A few characteristics of the subsea meters are:
- • Designed for ≥ 25 years lifetime with no maintenance
- • Covers all flowregimes and the full range of gas fractions (GVF) and water cuts (WLR)
- • Designed and qualified as per 13628-1,4 and ISO 10423 (API 6A and 17D).
- • Sour service - NACE compliance.
- • Electronics System - ruggedized design, consisting of high quality components only.
No sampling - The MPM meter does not require any subsea sampling.
The associated operational and economic savings versus the requirements of conventional meters are substantial, especially in subsea installations.
The meter measures the water salinity, and is very roubust to variations in the other configuration data.
Design Criteria
Our Subsea meter withstands:
• a depth of 3500 meters (11 600 ft)
• a pressure of 1000 bar (15 000 psi)
• a temperature of 250° C (480 °F)
• and any attempt at comparison!
High Quality ElectronicsThe electronics system in the MPM Meter is a ruggedized design, consisting of high quality components only.
The same high-grade electronics is used in topside and subsea meters. For subsea meters, a back -up system is offered to increase redundancy, and the subsea electronics has a number of housekeeping sensors to measure the conditions inside the electronics box:
• Humidity
• Water Ingress
• Temperature
• Pressure
• Shock / Vibration,
The electronics has an internal memory of 2 GB for raw data storage
Measuring Water Salinity
In a multiphase and/or wetgas application, there are several important reasons for why the salinity of the measured water should be determined:
• Automatic field configuration - Multiphase. All multiphase meters require information about the gas and fluid properties (PVT data) as configuration constants. Even though the MPM meter is less sensitive to salinity variations than conventional meters, the water properties are important for accurate measurement of the oil flow rates for wells with high water content. The MPM meter can automatically measure the water conductivity and the water density in water-continuous emulsions. This may eliminate the need for taking and analyzing samples. For subsea applications, this is particularly valuable.
• Detection of salt water break-through - Wetgas. The Salinity measurement will detect if and when salt water is breaking through and flowing into the well. This helps enhancing well performance, and optimizing the amounts of chemical inhibitors to avoid corrosion and hydrate formation in the pipelines.
• Determination of what kind of water is produced. When the salinity of the produced water is known, the water can in fact be split in formation and condensed water. This is important information which may contribute to better understanding the reservoir and enhancing the recovery from the reservoir.
The measured conductivity is converted into water salinity, and the water density is calculated, assuming a certain composition of the salt (for instance NaCl). The measurement method is based on RF measurements and MPM’s patented 3D Broadband technology.
