Over the past few years, MDD has performed a variety of ship modification and repair projects for the Military Sealift Command (MSV) and the United States Coast Guard (USCG). These ship repair tasks provide swift and exact support of US Navy, MSC, USCG, and commercial ship repair and modification efforts.
One of the projects completed was modifications to the USGC Cutter CGC Vigorous. The scope of effort included removal of the Emergency Diesel Generator’s overhead fuel tank and replacement with a new, custom-designed tank, including an improved fuel supply piping system. In addition, MDD performed the removal and relocation of the Emergency Diesel Generator’s cooling water Sea Strainer, including all associated piping and fittings. This project enhanced the EDGs performance capabilities and optimized the available operating space in the CGC Vigorous‘ EDG compartment.
The USNS LEWIS B. PULLER (T-ESB-3) is the first purpose-built Expeditionary Mobile Base vessel for the United States Navy. It is 764 feet long and has a full load displacement of approximately 78,000 tons. The ship was delivered to the Navy on June 12th 2015.
As delivered, the Puller’s fire main system consisted of 12” CuNi piping with each section connected with carbon steel “Dresser” couplings. Shortly after delivery, the ship experienced failures with the dresser couplings. The failure of the dresser couplings was a major concern and the ship could not sail without it being corrected. In July 2016, under contract N32205-16-P-4512, the Military Sealift Command engaged MDD to develop a test platform to evaluate methods for correcting the fire main piping system problems. The test platform was designed to replicate the piping configurations on the ship and evaluate different repair methods. Based on the results of the testing, it was determined that CuNi flanges would be welded to the pipe and stainless steel coupling would be used. MDD then performed the piping system modifications on the Puller. As the prime contractor, MDD had overall responsibility and provided project management, quality control and oversight. MDD subcontractor, Walashek Industrial and Marine, provided the pipe fitting and shipboard installation service. The piping modification was successfully completed under a very tight timeframe and all work received ABS approval.