Excellent Engineering Solution in Compressor Area to Avoid Project Delay

Abstract Green field projects always have an advantage in terms of optimization because everything can be planned with a calculated time barrier. Whereas for brown filed projects, it is a difficult task due to multiple challenges such as limited shutdown time, limited layout space, accessibility for construction, and so on. This paper demonstrates an excellent engineering solution for overcoming these challenges while replacing the existing compressor without requiring major piping/civil modifications. During a routine asset integrity assessment, it was decided to replace one of ADNOC GAS's existing compressors with a similar one that had the same footprint, nozzle sizes, and orientations. As a result, no significant engineering is required, and only minor adjustments may be required, which can be managed as residual engineering during construction. Consequently, the Purchase Order for the compressor was placed before any engineering activities based on the limited period of the shutdown window. Since the existing compressor was very old and the design data was unknown, it was difficult to determine the nozzle loads. However, based on the new compressor design data/ nozzle loads, a stress analysis with existing piping configurations is required to ensure the piping system's integrity. It was identified that the new compressor nozzle's allowable loads are much lower as per the latest design code, API 661. The existing piping configuration is imposing more loads than expected due to the need for more flexibility in piping layout configuration. Moreover, the new compressor vendor denied the request to increase the nozzle loads. Consequently, the existing piping routing has to be modified to achieve flexibility in the piping system and meet the nozzle load requirements. With the available shutdown window, there was no time to obtain additional pipe material or change civil supports. To overcome this situation, enhanced engineering with specialized stress analysis skills and advanced techniques were used to study various options for minimizing the piping/civil modifications as much as possible while meeting the nozzle loads. The best engineering techniques include utilizing the existing support locations, minimizing piping routing/support modifications, and minimizing civil and foundation modifications. By doing so, the compressor was installed without any changes to the vendor's technical requirements and with significant cost savings in implementation while adhering to the available shutdown window.