"We believe procedural automation supports and drives the consistent use of SOPs [standard operating procedures], and that it leverages and institutionalizes the knowledge of experienced operators," Hawkins said. "We believe that automating steps in the SOP increases reliability and safety, but without decreasing the importance of the operator's role in execution."
Chevron currently is using Yokogawa's Exapilot Modular Procedural Automation (MPA) tool to guide operators step-by-step through production well start-up procedures. Other applications include "compliance testing, manifold valve alignment, equipment swapping," Hawkins said.
"Oil wells don't simply come on with the turn of a valve, Hawkins said, explaining the operational complexities involved with ramping up production well. "They need to be ramped up and ramped off slowly so that pressures equalize and safety can be checked," Hawkins explained.
"We felt that a consistent well ramp-up procedure would minimize the amount of time required to get to full production and remove the variance between crews and between the experience levels of operators," Hawkins said.
"Historical data indicated that ramp-up time was not the same for different operating crews; ramp-up time took longer than expected; and times varied significantly," Hawkins said. Upon further examination, they found that written procedures were not up to date, and that the overlapping start-up of multiple wells meant that none had the operator's full attention. "Operators would make a movement at the top of the hour and then another at the bottom of the hour, regardless of whether the well could be ramped up more quickly," Hawkins said. "This got wells open, but wasn't very efficient."
Operator Involvement Critical
To begin to improve execution, Chevron began by creating one updated consensus operating procedure with significant input from the operators themselves. "We developed the Exapilot procedure as a tool to aid the operator, not replace him, and we needed buy-in from the operations staff to make this work," Hawkins said. The procedure allows the operator to easily manage multiple wells and determine when to make well choke changes based on pressure stability criteria rather than at a fixed time, like "bottom of the hour."
"We used the dynamic simulator we had access to and prototyped the Exapilot procedure list and validated the procedure steps with the operators," Hawkins said. "Not every plant will have a dynamic simulator, but we think this was extremely useful in allowing us to check the procedures before trying to implement them in the field."
Once they had prototyped the procedures in the dynamic simulator, Hawkins and his team implemented the Exapilot modular automation procedures in the operating environment. The training of operators on the new procedure was critical. Operators needed to understand how the automated procedure makes decisions and executes steps, so they don't intervene if things are actually working, but do intervene when there is a problem. The team monitored results and developed metrics to monitor performance.
"Now that we have the procedures in place," Hawkins said, "we can monitor performance. If it should take 12 hours, it should take 12 hours, and if it doesn't, there should be a very good reason."