Two Nuovo Pignone MS1002 Turbo-Compressor Controls for AGIP in Nigeria
HPI provided service and an overhaul for AGIP’s Nuovo Pignone gas turbines at the OB-OB gas plant. Initially, an HPI representative was requested at the plant to investigate overheating problems inside several Nuovo Pignone gas turbine enclosures. It was determined that approximately 3 years previously, the existing fire protection system was replaced with a CO2 fire protection system. With some of the turbines, the systems were not fully functioning currently, and some of the CO2 bottles were missing. HPI concluded that the major reason for the detectors failing could be due to short circuits in the original 25-year old cables.
HPI provided a few recommendations to AGIP for their consideration: Rewiring, re-specifying, and replacement of gas detection components; installation of exhaust duct fan motors to reduce overheating; inspection of the control systems and repair of the machine that has a hazardous gas path leak; and development and oversight of a plant-wide maintenance program. AGIP decided to upgrade the control system for its two GE Frame 1 units packaged by Nuovo Pignone.
HPI supplied qualified personnel to work onsite and remotely from the HPI headquarters. The typical roles of the onsite HPI employees included: Site manager for overall processes/procedures and interfacing with the customer; property manager to manage sign-out log for stores, inspection, and lay down area coordination; four supervisory advisers with strong mechanical, instrumentation, hydraulic, rig/crane operating, and ASME-code compliant welding skills; and an assistant technical advisor to help in all areas and manage the QA/QC and safety procedures.
The replacement controller for the new turbine control systems was based upon the Allen-Bradley ControlLogix™ PLC. The PLC was connected with the I/O via an Allen-Bradley Flex I/O™ interface system over a ControlNet™ communications network. Each Flex I/O module was mounted on a separate terminal base and mounted directly on standard terminal rails on the rear panel of the control cabinet.
The HMI on each control panel was based on the Allen-Bradley PanelView Plus 1250, 24 VDC with touchscreen color display.
HPI supplied the digital turbine control systems, which were designed for easy retrofit onto the existing turbine units. These systems replaced the existing control system and supplied its unique fuel governing software written in Ladder Logic on the ControlLogix PLC, providing all governing functions. All of the engineering, design, and manufacturing was carried out at the Houston headquarters office.