I recently sat down with an automation manager responsible for a subsection of a large manufacturing business. His company is embarking on an effort to standardize the use of process control narratives for all automation projects. To my surprise, the concept of process narratives was new to him. He didn't understand their purpose. But he was intrigued and asked many good questions I was happy to answer.
Simply put, a process control narrative is a written description of a manufacturing process that details the steps needed to start up, maintain an ideal running state, and safely shut down the system.
When is it written?
While a narrative can be written anytime, they are most often created at the onset of a large capital project, such as the installation of a new system or the retrofit of a legacy system. Why? Because kicking off a successful capital project requires a common understanding across several groups of stakeholders on how the manufacturing process will work. For example, the plant engineering team, the system integrator (SI) who is developing the control system, and the plant operations team all must agree on and understand how the process will work.
Who should write the narrative?
Ideally, the plant engineering and operations team should create the documents. This ensures that the plant operations staff owns and completely understands the process. All too often, the control system programmers, typically working for an SI, have key knowledge of the system that is undocumented. This creates a major risk when the SI transitions to the next project, because that knowledge leaves with the team. However, don’t forget that innovation requires collaboration. While plant staff writes the narrative, they should seek opinions and different view points from other stakeholders.
What should be included in a narrative?
A proper narrative will include equipment numbers and descriptions, detailed descriptions of the modes and sequence of operation, how the system will respond to upsets, how the system will ensure personnel, food, and environmental safety, and more. The exact details of what that more includes will depend on the nature of your company. There is no fixed format.
It must take serious effort to write a proper process control narrative. Is it worth it?
Yes. Writing a process narrative is not a quick or particularly easy task. However, if you are serious about innovation and improvement, it’s a necessary step in the process. Let’s consider the benefits of writing a process control narrative:
1. Process optimization—I cannot think of single way to drive process improvement more effectively than having a subject matter expert (SME) on the system sit down and write out the process step by step. Sharing this description with colleagues challenges them to think of better, faster, or just different ways of doing things. Before long, your plant staff will uncover innovations that directly apply to the company’s bottom line.
2. Knowledge transfer—Process knowledge is mission-critical to a manufacturing business. It’s how a company stays a step ahead of the competition by making product better, faster, and cheaper. You’ll need to have process documentation you can use to train future staff. Too often companies lose valuable intellectual property when key resources resign or assume new roles.
3. Documentation for programming team—Process narratives provide clear instructions to your process control programming team, whether internal to your organization or a third-party SI. This will decrease development time and help your startups to run smoothly. Both will save your organization money and save you serious headaches.
Does your organization utilize process narratives for automation projects?
This post was written by Jason Montroy. Jason is a customer relationship manager at MAVERICK Technologies, a leading system integrator providing industrial automation, operational support, and control systems engineering services in the manufacturing and process industries. MAVERICK delivers expertise and consulting in a wide variety of areas including industrial automation controls, distributed control systems,manufacturing execution systems, operational strategy, and business process optimization. The company provides a full range of automation and controls services – ranging from PID controller tuning and HMI programming to serving as a main automation contractor. Additionally MAVERICK offers industrial and technical staffing services, placing on-site automation, instrumentation and controls engineers.