Honeywell on meeting the metering challenge
18 June 2019
By Eric Bras (pictured), Global Product Marketing Manager, Honeywell Process Solutions.
Metering measurement accuracy is critical to profitability, efficiency and safety in natural operations. Inaccuracy risks compliance failures, legal disputes and increased gas that is lost or unaccounted for. It can rapidly erode profits and irreparably damage reputations.
By their nature, measurement errors are rarely random. Rather than balancing out, they accumulate. Even small errors can lead to substantial losses over time. An error of 0.5 percent in gas measurement can easily account for losses of more than $1 million a year – for a single meter.
The importance of monitoring high-pressure equipment is increased by a broader hydrocarbon mix and increasing occurrences of impurities in the gas in a larger number of pipelines.
Handling high pressures and wide flow ranges, eliminating compressors and moving parts, ultrasonic meters are the solution for modern custody transfer operations. The build-up of contamination and/or liquids inside the pipe can have a significant impact on the accuracy of ultrasonic meter readings, however. For this and other reasons, they must be properly monitored and, where necessary, maintained.
The challenge of doing so is made greater by two factors: remote, dispersed operations and metering stations and a significant loss of expertise and knowledge from the industry as a generation of experienced engineers retire. Combined with competitive pressures, operators are frequently required to monitor and maintain a growing number of high-pressure assets with a dwindling number of experienced staff.
Thus, the risks of undetected errors in metering grow while operators struggle to be everywhere, all the time.
A cure worse than the disease
Gas lost or unaccounted for due to meter errors is not the sole cause of inefficiency in the metering operation. Costly maintenance can also undermine profitable operations.
At least part of the driver for increased use of ultrasonic metering has been the superior reliability and consequently lower maintenance costs that the solution promises compared to alternative technologies. Ultrasonic meters have no moving parts and transducers (which detect and convert the ultrasonic pulse used to calculate the speed of the flow) that can be quickly cleaned and replaced –without shutting down or depressurizing the system.
Most operators opt either for periodic recalibration per a fixed timetable, or risk-based maintenance programs in which the periods between calibration can be extended by a defined limit if there is evidence of stable measurements. However, both inevitably result in recalibrations taking place when there is no measurement error. This adds to maintenance costs and reduces asset utilization.
Time-based and risk-based maintenance strategies are not merely inefficient; they can also be ineffective. Measurement errors that develop between calibration dates can go undetected, particularly in large, complex operations with a high number of metering stations or where meters are geographically remote.
Condition-based monitoring (CBM) tackles this waste by eliminating unnecessary maintenance and recalibrations without compromising confidence in meter readings.
Properly applied, a CBM program will allow maintenance to be targeted at those meters that need it: where indicators show performance deteriorating or evidence of impending equipment failure – before it occurs.
There are two prerequisites for this. The first are analytics that allow operators to reliably identify the meters requiring calibration. They should include changes in the flow meter as well as changes in the environment in which meters operate. The findings then need to be translated into actionable intelligence for operators so they can quickly identify the meters requiring maintenance and what exact actions need to be taken.
The second prerequisite for an effective CBM strategy is a method to capture, consolidate and centralise the data required for that analysis – in real time. This gives users visibility of their high-pressure assets and enables them to manage that maintenance centrally to ensure it takes place before failures or errors emerge.
Advanced diagnostics and analytics combined with an intuitive HMI and intelligent alarms address the challenge of the right analytics. Diagnostic dashboards give users an at-a-glance, real-time overview of all gas metering stations, with warning levels and alarms to identify those meters requiring attention, allowing users to rapidly drill down to diagnose the issue.
They provide real-time alerts when parameters exceed limits, so that errors and risks to reliable meter measurements do not remain undetected. They also provide analysis of historical data to see when and why issues occurred. Users can, therefore, reduce the maintenance of assets without compromising measurement certainty.
In addition, the cloud provides significant benefits such as scalability and unrestricted computing power. Perhaps more significantly, it provides a way to connect to a large number of dispersed metering stations, wherever they are located. Meters connect to a simple edge device at each metering station. Combined with the highest levels of cybersecurity, the data can then be processed and analyzed in the cloud – and securely accessed by users anywhere in the world with a web browser or an app on their mobile phones.
The solution provides businesses with 24/7 visibility and real-time monitoring of all their metering assets and can be used to effectively outsource metering monitoring and maintenance to a provider. Since the solution can be accessed through the web, it also enables businesses to collaborate across the enterprise, and leverage expertise from across the World. Finally, it allows users to centralize security with automatic updates of the software, again helping to reduce costs in the metering operation.
Ultrasonic metering provides reliability and measurement certainty. But these benefits are only fully realized if firms can implement both efficient and effective maintenance programs for their high-pressure assets, through strategies that can be deployed at scale and across widely dispersed operations. Connecting meters using the cloud allows operators to do both and use diagnostics and analytical tools to give them real-time visibility of the metering operation.
If the industry wants to maintain the level of measurement certainty needed as operations become ever more complex, connected solutions will play an increasing role. While operators still cannot be everywhere, these solutions allow them to see increasingly more across the enterprise and act accordingly.
For more information, please visit: www.honeywellprocess.com