Weatherford's Optical-Sensor Data Handling

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• Overview of the Optical-Sensor Data Handling
• Connection to Platform Automation System
• Network Accessible Storage

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• Optical-Sensor Data Handling

Overview of the Optical-Sensor Data Handling

Those who rely on data produced by in-well optical sensors are typically well site production engineers, reservoir engineers, and other operations-related staff within an oil company. The needs of each differ slightly and can vary at different phases of a reservoir's lifetime. Therefore, the following information is compiled for the use of those concerned with the integration of data supplied by Weatherford optical sensing systems into oil company data access and management systems.

The diagram below shows a typical offshore platform arrangement:

Historically, MODBUS protocols connected to supervisory control and data-acquisition (SCADA) systems or remote-terminal units (RTUs) have enabled platform production staff to correlate and combine production monitoring data. To maximize the benefit of the optical sensors, the reservoir engineer requires access to data stored at the highest data density possible. All of the Weatherford surface data systems compile data onto local storage media at high rates, ensuring easy access through local or wide-area networks (LAN/WAN).

The data-acquisition system software continually undergoes updates and improvement, based on input from the field. Maintenance and upgrade installation can be conveniently performed onshore if the systems are connected through a network, minimizing downtime and reducing the costs associated with transporting technicians to remote, offshore locations. In addition, connecting the systems to a network allows experts to support the software from locations around the world.

Weatherford encourages operators to connect optical data-acquisition systems to both the platform SCADA as well as the business wide-area network. The benefits of connecting the optical surface systems to a LAN/WAN are as follows:

• Insurance that backup data on the logger can be readily accessed over network if the SCADA/data historian link fails
• Easy access of higher-density data on the data logger after unplanned events, such as well shut-ins
• One shared network for MODBUS TCP/IP and OPC
• Remote troubleshooting, reconfiguring, and upgrading through the network from onshore locations
• Access to the structured-query-language (SQL) database through standard open database connectivity (ODBC)

Connection to Platform Automation System

Several kinds of optical surface data-acquisition systems are available. Nearly all of the deployed systems are designed to complement a particular well site arrangement; however, the software guiding these systems is identical and is called the Reservoir Monitoring System (RMS).

Weatherford's surface systems have a variety of connectivity options, all of which are easily configured at the time of installation. No programming or advanced, custom engineering is necessary. The chart below summarizes the options available:

Weatherford surface systems can be connected to well site automation systems in the following ways:

• Modbus
• CSV ASCIl string
• OPC
• PROFIBUS
• Database
• Flat files

Each of these is described in the following paragraphs.

Modbus Connection to Platform Automation System

Three MODBUS message types are supported: ASCII framing, RTU framing, or TCP/IP.

CSV ASCII String Connection to Platform Automation System

The CSV (comma-separated variable) string output format is not only useful for diagnostic and test purposes, but also for data transfer to third parties who do not support any of the SCADA-type formats. The protocol is simple enough for receiving programs to be expediently written.

Data format

Coding ASCII

Number of bits per character

Data 8
Parity None
Stop Bits 1

Message framing

Well Name<comma>Date<comma>Time<comma>Value 1<comma>Value 2<comma>...... Value N<CR><LF>

Example

NewWell,6/13/2005, 14:43:26, 196.41786194, 75.53485870
NewWell,6/13/2005, 14:43:29, 196.26698303, 75.57905579

OPC Connection to Platform Automation System

The RMS OLE for process control server (OPC) and client are fully compatible with the OPC Data Access 2.0 standard. Data transfer options include individual items or variable arrays.

Flow rate can be expressed in downhole conditions, separator conditions, or standard pressure and temperature conditions. The second pressure/temperature (PT) gauge is used to measure differential, from which density is derived.

PROFIBUS Connection to Platform Automation System

PROFIBUS is offered as an optional add-on for control room RMS systems only. The RMS system uses PROFIBUS interface cards and software drivers supplied by Softing, Inc. The PROFIBUS option offers several benefits:

• Provides an intelligent PC interface card for integrating a PC in a PROFIBUS network (1-channel)
• Provides master/slave functionality with a separate micro-controller for the protocol software
• Delivers a transfer rate of up to 12 mbit/s
• Supports all PROFIBUS protocols (multi-protocol support)

Database Connection to Platform Automation System

Weatherford's RMS software contains an SQL database. In addition, an ODBC driver is available for direct interconnection to other databases.

Well Sensor History Table:

Table Name : WellSensor_History
Description : This table has information about all sensor tables.
Table Layout :

Date Time Stamp	Well Name	Sensor Name	Sensor Type	Depth	Data Table Name	Status	Age

Well Sensor Current Table:

Table Name : WellSensor_Current
Description : This table has information about the sensor tables for the current configuration.
Table Layout :

Date Time Stamp	Well Name	Sensor Name	Sensor Type	Depth	Data Table Name

Pressure Sensor Data Table:

Table Name : WellName_SensorName_Date_Time
Description : This table stores the data for this pressure sensor.
Table Layout :

Date Time Stamp	PRS	PRS Status	TMP	TMP Status

Flow Sensor Data Table:

Table Name : WellName_SensorName_Date_Time
Description : This table stores the data for this flow sensor.
Table Layout :

Date Time Stamp	PRS	PRS Status	TMP	TMP Status	BV	BV Status	SS	SS Status

Continued ....

Oil FR	Oil FR Status	Water FR	Water FR Status	Oil PF	Oil PF Status	Water PF	Water PF Status

Three-Phase Flow Sensor Data Table:

Table Name : WellName_SensorName_Date_Time
Description : This table stores the data for this 3 phase flow sensor.
Table Layout :

Date Time Stamp	PRS 1	PRS 1 Status	TMP 1	TMP 1 Status	PRS 2	PRS 2 Status

Continued ....

TMP 2	TMP 2 Status	PRS_DH	PRS_DH Status	TMP_DH	TMP_DH Status

Continued ....

PRS_STD	PRS_STD Status	TMP_STD	TMP_STD Status	PRS_STD	PRS_STD Status

Continued ....

TMP_SEP	TMP_SEP Status	BV	BV Status	SS	SS Status

Continued ....

Oil FR_STD	Oil FR_STD Status	Water FR_DH	Water FR_DH Status	Gas FR_DH	Gas FR_DH Status

Continued ....

Oil FR_STD	Oil FR_STD Status	Water FR_STD	Water FR_STD Status	Gas FR_STD	Gas FR_STD Status

Continued ....

Oil FR_SEP	Oil FR_SEP Status	Water FR_SEP	Water FR_SEP Status	Gas FR_SEP	Gas FR_SEP Status

VelSOS (Velocity and Speed of Sound) Sensor Table:

Table Name : WellName_SensorName_Date_Time
Description : This table stores the data for this VelSOS sensor.
Table Layout :

Date Time Stamp	BV	BV Status	SS	SS Status	Total FR	Total FR Status

DTS Sensor Table:

Table Name : WellName_SensorName_Date_Time
Description : This table stores the data for this DTS sensor.
Table Layout :

Date Time Stamp	DTS Data	Zone Alarms

Flat Files Connection to Platform Automation System

If the RMS system is not configured to use a database and is directly connected to a network through the control computer or through a network-attached storage (NAS) server, the data can be accessed through flat files. For each PT gauge and each flowmeter, an ASCII data file is created every 24 hours, at midnight. The file is tab delimited, and the units of measure are in SI units.

Example of a PT gauge file:

Example of a two-phase flow meter file:

Each file name is appended with the date, for example: Psensor 1-22Oct2001.dat

DTS data are depth based rather than time based data. Therefore, they are formatted differently. DTS files adhere to the Canadian Well Logging ASCII Standard (LAS). Both LAS 2.0 and 3.0 standards are supported. The depth data are referenced to the wellhead, negative depths indicate surface cable, and positive depth numbers indicate in-well data. A typical file name is “DTS Sensor- 08Apr2003-1104.las”. An example LAS file is shown below.

Network Accessible Storage

NAS servers are self-contained, intelligent devices that attach directly to an existing LAN. A file system is located and managed on the NAS device, and data is transferred to users over standard network protocols such as TCP/IP. Weatherford uses Quantum's Snap NAS devices.

NAS drives offer larger data storage capacity than local hard drives and protect the investment made in acquiring the data. The SNAP servers are RAID 5 striping with parity (factory default), and RAID 1 monitoring. Another advantage of storing data files on a NAS device is no executable files are running on these servers. Therefore, network corruption is minimized, while control and communication to the computer is restricted from casual users on the network.