A review of the new OSA® +Flow solution from Bedrock Automation

Each year, billions of dollars’ worth of oil and gas change hands, and both buyers and sellers have much vested in ensuring that there is an accurate record of the transfer. Inaccuracies on both sides of the transaction could result in windfall profits for one party and significant losses for the other. Lease allocation (or automatic) custody transfer (LACT) is the best way to ensure the fair and effective ownership exchange of hydrocarbon fluids.

LACT measurement includes calculations with flow-weighted averages and a detailed record of the transaction. This also includes all logs and evidence that validate the measurement. The measurement should reveal if the flow rate is more or less than the validated rate of the meter, which could be the result of imbalances in calibration. Even a half-degree difference in temperature could mean the loss of hundreds of thousands of dollars. The flow computer must accurately flag any change that could influence measurement, which helps not only to ensure fair and effective ownership, but also improves compliance with the custody transfer.

As such, changes in the measurement and automation industry have been followed closely, and the value of applying them to the world of LACT is being assessed. Most legacy flow computers were developed when digital capabilities were still in their infancy. Today there is much more complexity at the operations level, while information technology is also making quantum leaps in connectivity and performance.

Figure 1: LACT units function like cash registers, providing a detailed record of oil and gas transactions. Source: BedrockFigure 1: LACT units function like cash registers, providing a detailed record of oil and gas transactions. Source: Bedrock

Meanwhile, legacy vendors are discontinuing their current systems and offering new models, but things are moving so fast that even their new offerings are practically out of date already. Consequently, it is now clear that a new generation of flow computers like the OSA® +Flow from Bedrock Automation would be necessary to move LACT to a modern level of performance and cost-efficiency.

Flow-Cal inside

First and foremost, any flow computer must be accurate and reliable, and Bedrock OSA +Flow covers this in spades by incorporating flow calculations from Flow-Cal and the American Petroleum Institute (API). Flow-Cal is the well-known industry leader in oil and gas measurement and data management for natural gas and petroleum liquids. As such, Flow-Cal has worked closely with the American Petroleum Institute (API) to develop code for proving, measuring and testing flow calculations and is, in fact, the leading worldwide provider for API calculations code. Flow-Cal is the benchmark against which API validates flow technologies.

Thanks for the memory

Figure 2: The Bedrock OSA +Flow solution. Source: BedrockFigure 2: The Bedrock OSA +Flow solution. Source: BedrockMemory (both program RAM and flash storage) is critical for this new generation of flow measurement as memory impacts the number of meter runs, reports and sockets that can be run, and the OSA +Flow provides 512 MB of RAM and 64 GB of flash memory as compared to existing legacy systems, which provide a small fraction of both. Some vendors have tried to increase memory but are playing catch up.

Most existing legacy systems, for example, have only enough memory to support a few Ethernet sockets, which limits the number of devices that can communicate simultaneously with the end device. Once all sockets are taken, the device is no longer accessible via Ethernet, and if the HMI socket is also already taken by another polling device, the screen drops communication altogether, leaving local operators or truck drivers without a communication path to the flow computer. Memory limitations also restrict simultaneous calculations for gas and liquid meter runs, the number of reports that can be stored and audit/alarm log size.

Integrating flow measurement with control and communication

Given their limited memory capacity, legacy systems have maximized the number of available meter runs, while generating reports and device communications. Integrating control functionality was all but out of the question. Recognizing the benefits of being able to deploy integrated measurement and control, Bedrock Automation designed a universal platform in OSA +Flow that exploits the latest in advanced multi-core digital semiconductors for extreme computation and communication performance, enabling concurrent operation as both a high-performance programmable logic controller/remote terminal unit (PLC/RTU) and a best-in-class flow computer.

The more complex the operation, the greater the need to sync and phase terminals and facilities. Right now, many oil fields remain unconnected but as producers have more difficulty finding talent, they will need more capability for remote operations and more flexibility to take advantage of the cloud and other emergent technologies. The OSA +Flow performance and open connectivity provide that.

With a non-integrated system, a separate database to address control requirements must be generated. The data may appear as a block from which real-time flow data can be gathered; variables like temperature and pressure calculated; and analysis performed. However, the user would not be able to access much history or connect to anything else.

Additionally, as more oil and gas companies employ cloud and digital communications, Bedrock is again ahead of the competition in supporting open communication protocols such as open platform communications unified architecture (OPC UA) and message queuing telemetry transport (MQTT), which are increasingly becoming the protocols of choice for communication among diverse applications and devices.

A single set of zero-cost engineering tools

Integrating flow computing and control tightly in the same device offers oil and gas automation users a single set of tools. This boosts productivity and accuracy, which translates into higher profits. So instead of having separate PLC and flow measurement devices, each with a unique software package and the need for training that goes with it, Bedrock’s integrated platform makes life easier for LACT skid makers and end-users. Recognizing how important measurement is, the OSA +Flow application is protected so that no changes can be made to the application, and all performance metrics are available to be monitored so that the user can be assured that the measurement performance is not affected by the control applications.

Baseline licenses for the engineering environment of traditional flow computers or PLC/RTUs can range from $1,000 to almost $10,000 per installation and there are typically additional licensing costs for additional applications. With Bedrock OSA +Flow, a versatile IEC 61131-3 compliant engineering toolset is free regardless of how many users and applications are deployed.

Software-defined input/output (I/O) is a joy to use

No matter how capable the flow computer, if it is difficult to use, it will be less effective as well as more expensive to own. Bedrock OSA +Flow provides truly software configurable I/O to make life easier for the system developer. If a typical flow measurement application required supervisory control and data acquisition (SCADA) mapping of live and batch data, temperature and pressure might be mapped to hard-coded device registers. With Bedrock Automation’s open platform model, however, registers are software-defined versus predefined logically, simplifying implementation and SCADA configuration.

Configurable I/O has advantages in the field as well. Users can simply map to the right devices and protocols in the field. If revisions are required, users can re-configure right there, without having to go back to inventory to get a specific module type. Both the control and flow aspects of the Bedrock system are well defined, and the OSA +Flow is offered in both a single box version, with up to 20 universal I/O per flow computer, and also a backplane version, with up to 400 universal I/O per flow computer and with only a handful of part numbers needed for a complete system.

Maximum security and ruggedness

Custody transfer operators are already implementing some degree of security, isolating their networks and their data from other parties in the transaction, so there is a firewall of sorts. As such, custody transfer operators are beginning to realize the need for cyber security, and this need goes well beyond trying to protect systems with passwords. Because the OSA +Flow builds in the same industry-leading cyber security that is in all Bedrock products, there is no additional cost for providing custody transfer operations with the kind of user authentication and encryption technologies used by advanced military, aerospace and e-commerce applications.

The OSA +Flow product family is also designed for use in ruggedized environments. All OSA +Flow computers have additional cyber-physical protection with anti-tamper metal housings that are sealed from dust, water and other environmental assaults. Extreme operating temperature ratings of -40o C to 80o C are standard, as is UL listing, Class 1 Div 2. Additionally, Bedrock is the only platform that is 100% American made, including all hardware, software and development. No other flow platform vendor can say this. This is extremely important with producers on federal fields that have increasingly stringent supply chain requirements.

Perfect timing

Now is the perfect time to be evaluating flow computers. Existing systems have patches everywhere, and many may not even have SCADA or internet connectivity. Most users have already been notified that their current products are phasing out and will begin testing newer offerings soon.

So, as users test what their legacy provider is offering, it would be wise to look at a system that has been designed from the ground up for simplicity, scalability and security.

There are many customers that have been using their legacy flow computer as a PLC/RTU as well, but the programming capabilities on the flow computers are very limited, which has restricted what they can do. They finally have an option other than investing in an additional PLC; by replacing their flow computer with the OSA +Flow solution, they will have everything they need in a single, secure device.

The Bedrock OSA +Flow boasts memory capacity, software configurable I/O and extraordinary ease of use. Add in the Flow-Cal stack, free engineering software, industry-leading security and rugged housing, and there is nothing comparable.

About the author

Shawn Bellamy is president of G&C Optimization in Houston, which provides skid building and control panel fabrication services to the energy industry. Before that, he was a field specialist supporting RTU and other automation products for Puffer Sweiven, and, before that, director of technology at a charter school. He is an expert in the petroleum operations, electronic instrumentation, instrument calibration, troubleshooting, measurement and control application development fields. Shawn holds a Bachelor of Applied Science (B.A.Sc.) in Computer Science from the University of Houston-Victoria. For more information, email him at shawn.bellamy@gcoptimization.com.

OSA is a registered trademark of Bedrock Automation. Flow-Cal is a trademark of Flow-Cal, Inc.