Control systems trip management in the chemical industry
Abstract
The research was conducted by means of a study of literature and empirical methods. The literature study demonstrated that CSTs (Control System Trips) are very critical throughout the project life cycle in the chemical industry. There is however, a lack of engineering management interaction throughout the different phases, as well as effective front end loading and knowledge of CSTs. Knowledge gained from the literature study as well as personal experience, insight and practical knowledge of this field of engineering management were used to construct a plan that can be used throughout all the different phases of a project in the chemical industry herein referred to as the CSTMP (Control System Trip Management Plan) in South Africa.
The CSTMP was developed for each different phase of a project. The plan covers all reviews, tests, interface management, engineering management, and risk management, end of job / phase documentation, and so forth. The researcher submits that the CSTMP constitutes the issue of the new knowledge that he has contributed to the science of Engineering Management. The CSTMP is developed in detail in Chapter 4 of this work.
The CSTMP was applied to the Nigel PPS (Pressure Protection Station) project for evaluation. The CSTMP was not used until the basic engineering phase and calculated assumptions were made to compute the possible loss in cost. The Nigel PPS project was part of the natural gas network conversion project. The project consisted of the conversion of the Gauteng network from hydrogen-rich gas to natural gas from Mozambique. The total cost of the conversion was R373 million and it was successfully completed in June 2004. It is estimated that by implementing the plan, 4.7% of the cost could have been saved. The CSTMP was validated by means of several questionnaires, completed by control system engineers as well as by technologists and technicians. The aim of the questionnaires was to determine their knowledge regarding the importance of CSTs during project phases. The CSTMP was tested by means of two additional questionnaires which were issued to a dedicated group of engineering managers. The first questionnaire was analysed to determine the engineering managers' knowledge and competence. The second questionnaire was issued after a presentation on the CSTMP to determine the engineering managers' knowledge and acceptance of the CSTMP. The resulting data were statistically analysed and documented to confirm that the CSTMP will indeed make a contribution to the chemical industry in South Africa.
The problem statement addressed by this thesis states that projects in the chemical industry are executed without due cognisance of the engineering management of CSTs, causing rework, unsafe conditions, insufficient front end loading and no continuity in resources. It is crucial that an effective CSTMP is maintained throughout project phases for each new or refurbished project. The CSTMP could be applied to non-chemical plants in the industry.
The lack of a well structured and integrated CST management plan is a root cause of the lack of engineering management effort with respect to CST Management. The following main conclusions were drawn as a result of this work:
• Engineering managers should take cognisance of the requirements of a CSTMP and should implement such as part of their risk management accountability. The CSTMP will help engineering managers to understand and consequently, accept accountability for CSTs during all the different phases of a project.
• There will be a definite cost saving if a formal CSTMP is implemented during a project. Rework will be cut to a minimum and actions will follow in a logical sequence during each phase of a project. This was measured on a single project and could not be executed on several different types of projects, due to time and practical constraints. The CSTMP will also improve the front end loading of a project, due to better management.
• The CSTMP will ensure continuity across identified project phases. The plan will also highlight the importance of the CSTs on all the phases of a project. This enables the control systems engineer to become involved earlier in a project in identifying possible risks as well as continuity during the FAT (Factory Acceptance Test). During the FAT, all designs are integrated into a dedicated system, interfaces are clarified and training (operation and maintenance) finalised. An effective FAT will ensure a quicker and safer startup of a plant.