What is a digital twin?
There are several different types of digital twins. What they have in common is that they are in some aspect a virtual model of a machine, process, production line, building, etc. More concrete examples will be described below.
Why use digital twins?
Much of the benefit of digital twins is to quality assure the work as well as the facility itself. In other words, to have good order in the production plant. It also means that you can do both maintenance and construction much more efficiently, as you have a better overview of what you are starting from.
What are the different types of digital twins?
There are many different types of digital twins that can be categorised or split in different ways. In this article we will not discuss twins related to the product itself. Instead, we will focus on those digital twins that relate to the production facility and production:
- 3D model of the plant - a virtual model of the entire plant in 3D format to facilitate planning, maintenance, training and future development.
- Operation & Simulation - mirrors the production processes and enables development and testing of changes and new deployments.
- Plant information - central database for all technical plant information to streamline maintenance and increase plant uptime.
- Production performance - shows real-time production efficiency and output and allows analysis of historical production information.
1. Digital twins for the plant as a 3D model
In general, these models are created either in CAD during the design phase or during the scanning of the existing plant. Developments have progressed and improved with 3D scanned models using laser scanning, which is a method that has been used for a relatively long time. The technology is now mature and more cost-effective. A trending technique used in recent years is photometry, where a set of photographs is used to build a 3D model. This method is simple and is now seen as business as usual in production facilities.
What is the benefit of a 3D model of a plant?
- To familiarize yourself with the facility before physically visiting Location. Also, for example, in case of any kind of telework.
- To be able to search for individual objects and see their exact location.
- To simplify the work process, where it is dangerous to go out into the plant, difficult to access the plant due to physical distance, or in pharmaceutical factories with clean rooms where one should ideally not be.
- To gain an understanding of the state of the plant, for example before maintenance work.
- Planning evacuation routes and other safety-related matters.
- Knowing whether there is room to maneuver when dismantling a machine on Location and getting all the axles out, for example.
- To simulate certain maintenance actions. This is particularly true in facilities where access is expensive and difficult, such as an oil platform.
- To simulate emergencies for maintenance and operational staff without destroying the plant for real.
- To have a base/basis for future redevelopment.
2. Digital twins for operation and simulation
Digital twinning for operation and simulation really adds real value to automation systems, for example it is possible to test your automation system against a simulated reality before a commissioning or system change. This can be done at different levels, from just using, for example, opening/closing valves, to switching on dynamic simulation, to see how different media react in a reactor. This is done to reduce the commissioning time when implementing process changes in the plant and for quality assurance.
Other benefits can also be gained, such as allowing operators to practice simulated test runs safely and securely when running a plant. By the time the plant starts up for real, operators are already familiar with how the system and process work, and infrequent operating situations can be simulated so that operators get used to them.
3. Digital twins for plant information
There is a huge amount of technical plant information. It ranges from individual data that may be contained in some Excel sheet on pressure and temperature, to various data sheets, manuals, instructions, spare parts lists, etcetera. All these documents with information are today often scattered on various SharePoints, local files, and maybe even some individual PC. Managing such information and data is called Data and Document Management System (DDMS).
The benefits of a Data & Document Management System (DDMS)
Above all, a Data and Document Management System (DDMS) saves a lot of time. Today, maintenance staff spend a lot of time searching and verifying information before each maintenance action because documents are scattered in different places, individual data is in several places and once you find a few different documents, they may show differently.
In addition to saving time, a DDMS allows you to trust your data. For a pharmaceutical company, for example, it is important to be able to quickly retrieve the required information for inspections by authorities. The information also provides a good basis for rebuilding and upgrading. Something that becomes even more relevant is in the face of decommissioning and potential reuse of certain components, which is the trend towards more and more, as part of the sustainable society.
What's happening right now is that we're also moving into mobile solutions so that you can access your information on both your tablet and your phone when you're out in the facility. Whatever solution is chosen, it should support external parties and companies involved in the operation and maintenance of a facility.
4. Digital twins for production performance
A history server, Historian, collects and stores large amounts of data about how a specific process has performed by collecting all the real-time data from instruments and machines in the plant. The information data stored can be anything from specific valve positions, flow rates or temperatures - all values with associated time stamps. The information data is then available when you need to extract information on how a specific product has been manufactured, for reporting or analysis, such as a batch report.
When this data is stored in one place for a long time, you get a good digital picture of how the process is going in a plant over time. It is then possible to monitor and detect if there is anything out of the norm and also, for example, to identify specific patterns that can be used for predictive maintenance.
There are different types of digital twins that can be useful for plant process, operation, development, as well as maintenance. All available information can be managed through a Data & Document Management System (DDMS). The 3D model depicts the plant. Together and separately, these digital twins create real value.