Industry 4.0 and the Industrial Internet of Things (Industrial IoT) can help plants improve reliability, energy efficiency, productivity, and safety while reducing emissions and maintenance costs. By Jonas Berge, Director, Applied Technology, Plantweb Solutions, Emerson Automation Solutions (Singapore)
It can be difficult for plant personnel to keep up with maintenance tasks such as inspection, data collection, and review and analysis of field data – tasks that ensure plant reliability and help avoid losses and energy over-consumption. Not keeping pace could result in noncompliance, fines, maintenance budget overrun, disruption of production, or safety incidents. If you are like most people, you probably feel you have less time now than only a year ago. However, you can help yourself and your plant keep up by using new technology to enable the digital transformation of your plant.
Industry 4.0 For Process Industries
Industry 4.0 is mostly relevant to discrete products and their manufacturing – assembly lines, machines, and robots. Central to Industry 4.0 is information exchange over the entire lifecycle of a product. This means collecting and storing all data generated for a product throughout its life end-to-end, from design thru manufacturing, operation and repair, to recycling. This makes sense for discrete items like toaster ovens and cars, but not so much to continuously processed fluids. Another important aspect of Industry 4.0 is the ability to make single customised units, ‘lot size 1,’ to accommodate exact individual requirements. However, it does not really apply to continuous processing since there is no ‘lot,’ except in batch processing such as for speciality chemicals and pharmaceuticals.
In a process plant, the Industry 4.0 concept comes into play with respect to the processing equipment such as the pumps, heat exchangers, and cooling towers. For instance, a valve manufacturer can these days remotely monitor the condition of hundreds of control valves in a plant across the internet as a connected service based on Industrial IoT data collection. The valve manufacturer’s software analyses the data and notifies the plant of any impending problem. A pool of valve experts is available to support the plant personnel. That is, the operation phase of the equipment lifecycle is where Industry 4.0 meets Internet of Things (IoT) and we get Industrial IoT (Industrial IoT).
Closed Loop Maintenance
Imagine not having to collect data manually, especially on days when it is cold and icy, rainy and windy, or hot and humid. Imagine not having to analyse a huge backlog of vibration spectrums. Imagine simply receiving reports pinpointing where maintenance is required, automatically.
Across all industries, plants are now deploying additional sensors to enable the condition and performance of a broader scope of equipment (‘things’) such as pumps, cooling towers, blowers, and valves around the site to be monitored online from a central location. Sensors are also added to computerise energy management and improve situational awareness. This includes sensors for pressure, flow, fluid level, valve position, vibration, temperature, acoustic noise, corrosion, pipe wall thickness, electric power consumption, etc., depending on the application. These transmitters are often wireless as this is the easiest way to add more sensors to an existing plant. If the site uses digital Fieldbus, that also makes it simple to integrate additional devices. By automating data collection, plants become more productive as time is saved gathering data that then frees up personnel to perform more value-added activities like fixing small issues detected before they turn into big problems. Since data is more current, up to the minute or hour instead of weekly or monthly, maintenance becomes much more predictive.
Some plants prefer the in-house maintenance team to monitor the equipment ‘on-prem,’ while other plants prefer their equipment to be monitored by a pool of company experts from a corporate central engineering office. These experts are responsible for reliability and performance at multiple plants across a country or globally. And yet other plants prefer a third-party company to monitor the equipment as a connected service for a monthly subscription fee, which reduces the burden on the site personnel. For connected services, the sensor data is transmitted to the cloud.
A few methods are available to securely transfer the data to the cloud.
1. Many plants already have a Demilitarized Zone (DMZ) connection to the internet with back-to-back firewalls.
2. Cloud connection may already be provided by the plant’s historian.
3. The Industrial IoT can be a separate system not connected to the plant control system.
4. Use a data diode, which as the name suggests, is a network appliance that only allows selected data to leave the plant. There is no path to receive data, thus preventing attacks on the control system through this connection.
Note that the process is controlled from within the plant. The connected services are for asset monitoring.
In the cloud, which is nothing but a virtually unlimited number of servers with massive computing and storage capacity connected to the internet, software ‘apps’ are running to analyse the raw data from the sensors in the plant. These software apps are specialised for the task at hand, such as monitoring the condition and performance of equipment like pumps, compressors, blowers, valves, etc. The beauty of cloud computing is that the server machines need not be physically present in the plant, so they take up no space, you do not need your IT department to maintain them, and they can be accessed from anywhere in the world. The apps generate reports listing which equipment is in good condition and performing well and which equipment needs attention.
The reports are reviewed by the service provider’s experts for correctness and completeness before they are sent to the plant. Plant personnel act upon the recommendations, such as replacing, repairing, and adjusting equipment, thus closing the loop by improving equipment condition and performance.
Closed Loop Maintenance
Closed loop control is measure-control-actuate. Closed loop maintenance is see-decide-act. Sensors on plant equipment like pumps pick up vibration, temperature, and acoustic noise, allowing you to ‘see’ the equipment. Analytics software on-premise or in the cloud helps you diagnose the equipment and decide which need attention and which do not. Third-party connected services do the reporting for you, and experts provide the recommendations. The plant maintenance personnel simply act on the recommendations in the report. The service provider may also come to the site to carry out the overhaul.
Reliability apps are pre-built analytic software which can be integrated with the plant’s historian or can be web-based using HTML5 graphics, enabling them to be displayed in a web browser on a computer, tablet or smart phone from anywhere. Maintenance personnel could be in the cafeteria, in a meeting, or on the way home and still be able to access equipment health information instantly.
The apps use graphical representation in the form of colour coded dial gauges and trend charts. This includes health for the overall population of each type of equipment, and how many of them have critical issues, warnings, or are in good condition.
Equipment like pumps are identified by tag and location and specific tags can be sorted and searched. The list shows status, health index, problem description, alarm condition, and the length of time the equipment has been in this condition. The apps provide plain text problem descriptions. There is no need to interpret complex 3D scatter plots or spectrums. There is an early warning about developing problems, which allows maintenance personnel to intervene to prevent equipment failure. This health information can be used for risk-based inspection planning to prioritise and schedule daily maintenance and turnaround activities. By not spending time on a routine inspection of equipment which is in good condition, this instead allows focusing of resources on the equipment that needs attention.
The equipment health summary can be exported to Excel to be compiled into reports for use in meetings, etc., again saving valuable maintenance management time. The type of problems detected by the diagnostics algorithm depends on the type of equipment and how it has been instrumented. In the case of a pump, this may include pre-cavitation, low head, high seal temperature, high vibration, low flow, etc. A compound health index is also computed for each type of equipment allowing for easy prioritisation and optimisation of maintenance activities. The health index is based on a predefined weightage of each type of problem a piece of equipment has.
A trend chart of the health index and other pertinent information for each piece of equipment makes it easy to visualise if its condition is deteriorating significantly, and how fast. As the user interface is very intuitive, days of training are not required to operate the software and there is certainly no need to be a data scientist with a degree in analytics. The apps are designed for maintenance and reliability personnel. Compressors, blowers, and other equipment will be managed the same way as pumps. The digital transformation of work processes means maintenance and reliability personnel now check the software first before going to the field, while in the past they would always go to the field to first check what is going on. With the information from the app, maintenance engineers can quickly decide what action needs to be taken.
Reports And Experts
If the plant is using connected services, then it does not matter what the analytics software application looks like or how easy it is to use because the plant’s maintenance personnel need not use the application themselves. Periodic reports or text messages from the equipment monitoring service provider tells maintenance personnel what actions are required. In the case of connected services, it is the clarity of the reports which matter.
The report’s executive summary uses graphical pie and trend charts for the health of the overall sensors or equipment. The equipment can be viewed at a glance – for example, how many pumps are in good condition and how many have critical issues or just a warning. Other sections of the report list problem pumps and other equipment by tag including location information, health index, problem description, and how long the condition has persisted. The information in the report is used to prioritise and schedule daily maintenance as well as for turnaround planning, including workforce planning. The actions that come out of the report could be as simple as checking with operations if there is a closed valve obstructing flow causing pump cavitation; a reminder to fill up lube oil, or to schedule replacement of a bearing. The plant maintenance and reliability teams save time by reducing routine inspection. It also frees up expert resources, such as vibration analysts, to focus their effort on equipment which needs attention.
Thanks to cloud connectivity, personnel in multiple locations and departments can access the information at the same time, enabling new levels of collaboration between teams. Teams can consist of technicians at the site, subject matter experts at a corporate centre of excellence, third-party service providers, and original equipment vendors to discuss problems and plan solutions. Cloud connectivity also enables visibility of equipment from multiple sites in one central location to coordinate the deployment of maintenance personnel to the site.
Note that the data now collected automatically by the system and sent to the cloud is the same data, which in the past was collected manually for maintenance purposes, often by external parties taking it to their office for manual analysis. This type of data leaving the plant is not new, just more up to date and easier to use.
Energy Efficiency Apps
Energy Management Information System (EMIS) software is integrated with the plant’s historian to support efficient use of energy and utilities. The EMIS software also uses colour-coded dial gauges and trend charts, illustrating below target, on target, or over consumption of each energy stream such as water, air, gas, electricity, steam, etc. These consumption targets are computed dynamically by the equipment performance models in the software and from historical energy utilisation patterns.
For instance, based on the current production of steam, the models could predict what the consumption of water, fuel gas and electricity should be in real-time. Alarms are triggered on overconsumption. These alarms make it easy to detect when equipment like motors that are not in use are left running or run faster than required. Inefficient combustion and valves left open when not producing are targeted. Depending on the level of additional instrumentation deployed in the plant, the energy manager can drill deeper down into the plant hierarchy to see consumption for each plant area, unit and individual pieces of equipment. Such equipment includes pumps, air compressors, blowers, cooling towers, etc. This allows energy managers to pinpoint the source of the over consumption with finer granularity to help to troubleshoot. For plants adopting ISO 50001 energy management practices to reduce and sustain energy consumption, EMIS software saves a tremendous amount of time.
Digital Transformation To Keep Up
Getting the plant started on the path towards digital transformation begins with an operational certainty discovery session to uncover latent needs of each department in the plant; maintenance, reliability, process, safety, and operations etc. Based on the findings the second layer of automation with instrumentation and analytics software is proposed to keep the plant evergreen, improving reliability and energy efficiency, reducing maintenance costs, and saving people’s time, enabling them to keep up with their workload.
This makes the plant ready for Industrial IoT and Industry 4.0. Monitoring can either be on-prem or as a connected service provided by a corporate engineering centre or outsourced to a third party. Applying technology for digital transformation of work practices is critical towards saving time and money.