Repairs of Hurricane Damaged Platforms in the Bay of Campeche
Authors: Souza Marco , Bayazitoglu Yildirirn , Lu Li Shun , Valdés Victor , Vázquez Rogelio 
Published: October 2008

Several offshore platforms were damaged when the Hurricane Roxanne passed through the Bay of Campeche (BOC), Gulf of Mexico, in October 1995. A detailed assessment of the facilities was performed following the guidelines given in Section 17 of Supplement 1 of the API RP 2A-WSD, 20th Edition (Reference 1) and the transitory criteria for the design and assessment of existing platforms developed by PEPIIMP (Reference 2). Critically damaged platforms were identified for repair. The scope of repairs included jacket structural members and support framing for deck facilities. This paper gives an overview of various techniques used for repairs of the underwater jacket structural members and joints. Different underwater repair methods are discussed. Repairs of both jacket and deck damages caused by Hurricane Roxanne are presented as examples. The repair methods used are based on currently available technology and they will provide practical examples for economical platform repair in shallow, warm water environment.

Introduction

Hurricane Roxanne, of October 1995, damaged several platforms situated in the Marine Region of the Bay of Campeche, Gulf of Mexico. A sample of 51 from the nearly 200 platforms were selected by Petróleos Mexicanos (PEMEX) and Instituto Mexicano del Petróleo (IMP) for structural assessment. The selection was based on previous damage history, damages found during the emergency inspection campaign performed immediately after the passing of the hurricane, and the significance of the platform in the oil producing scheme. Thus, PEMEX and IMP decided to perform the assessment of the 26 platforms of the sample and the detailed engineering for the platforms found to require repair. Special inspections were scheduled and performed so the existing condition and damages of these platforms were properly documented. Special inspection reports were issued and the data obtained was analyzed in detail, which led to a final selection of the damages to be repaired. The major damages consisted of dents, cracks, a combination of dents and cracks, and buckled members. Of the original set of twenty six platforms selected for the assessment project, twelve platforms were found to have damages which required repair in order to preserve the integrity of the structure. On a per platform basis, the selected damages requiring repairs can be summarized as follows: two platforms required repairs in both the jacket and the deck, two platforms required repair in the deck only, and eight platforms required repair in the jackets only. Detailed repair engineering analyses was then carried out for the twelve platforms to be repaired, leading to the repair of 15 damages for the jackets and 9 for the decks. A list of the repaired platforms is presented in Table 1, where the platforms characteristics and the type of repair is indicated. Tables 1 and 2 contains a list of the repaired damages in both the jackets and the decks, respectively, per platform. The damaged members and nodes were labeled according to IMP'S identification system (PL-IDE). Different repair options were considered and the corresponding preliminary detailed repair engineering analysis was developed. The results obtained together with the recommended repair options were analyzed in detail, and the repair method to be used was defined for each damage.