A complex shutdown in limited time with limited space

Mammoet, the world’s largest service provider specializing in engineered heavy lifting and transport, completed heavy lifting, transportation and rigging activities at Chevron South Africa in Cape Town for their annual scheduled maintenance.  Megchem, an engineering company operating primarily in the oil, gas, power generation and energy related industries, contracted Mammoet for the refurbishment of a 350 ton reactor dome, replacement of a 400 ton atmospheric column and 400 ton heat exchanger. The shutdown started on schedule on 10 February 2017 and all components had to be replaced within 41 days. Therefore as much work as possible had been done leading up to the shutdown that was on a strict schedule.  With the shutdown happening during a windy time of year in Cape Town, special attention was paid to weather conditions.  Mammoet’s schedule and working hours were flexible so progress of the work would not be affected by wind delays and stay aligned within Chevron’s schedule.

The refurbishment of a heat exchanger column had to be executed with surgical precision as the structure around the column was extremely congested and left little room for maneuvering.  With no time to spare, due to strict time constraints for other contractors to complete their work on site, the preparations to install the new column started immediately after removal of the old column using a 400Te crawler crane and a suitable assist crane for the top and tailing purposes of the column. The old column was directly installed on a conventional trailer for transportation to the demolition yard 26km off site. To minimize impact on traffic, the column was transported in the early hours of the morning. For the refurbishment of the reactor the crane had to be assembled in an extremely tight location and the new dome and cyclones were built next to the crane in a specially designed structure leading up to the shutdown period.  Mammoet successfully and safely completed all activities at Chevron within the allocated timeframes and without lost time incidents, causing no delays for other parties involved in the shutdown.