Underwater CPP - Water In and Oil Out

Vessels are outfitted with Controllable Pitch Propeller systems making maneuvering a dream. Operators enjoy the benefits of their flexibility, but this flexibility does come at a price, as they require more maintenance and repair than a typical mono-block propeller system.

The fact is with more and more focus being placed on keeping our environment clean and green, even the smallest leakage of oil on propulsion systems require immediate attention and repair. The Subsea Solutions Alliance has procedures approved by major Original Equipment Manufacturers (OEM's) that allow CPP propeller blade palm seals to be exchanged with a vessel in water at it's NORMAL draft. Typically these repairs can be done while vessels are performing cargo operations with minimal to no off-hire time assessed.

During a routine underwater inspection while a military installation was on standby in a Far Eastern port, it was determined that there was some oil leakage from the CPP blade palm seals. The military personnel contacted the Original Equipment Manufacturer (OEM) and as such the OEM contacted their global diving partner, the Subsea Solutions Alliance to jump into action by deploying equipment and personnel from Subsea Solutions Alliance offices in California USA and Busan Korea. After an inspection dive, the diver / technicians from the Subsea Solutions Alliance confirmed the actual seals that were leaking and prepared for the blade seal exchange. Utilizing procedures developed together with the OEM, and subsequently approved by the OEM, the diver / technicians exchanged the blade palm seals without flooding the CPP hub or CPP hydraulic system with water of any type. No water entered the system, no system flushing was required, and a safe, simple and environmentally friendly method of repair was employed. Creating an "oil bubble" in the area of the CPP propeller hub just below the seal area, the hub and CPP hydraulic system was effectively "sealed from seawater intrusion. Using specialty equipment and unique techniques, the diver / technicians of the Subsea Solutions Alliance effectively managed the propeller blade to allow access to the seal for a proper OEM and Class approved repair. Working under the the close supervision of the American Bureau of Shipping under a procedure reviewed and approved in advance by ABS, the vessel was fully repaired and put back into service without dry docking or the need to off-load critical armaments and other equipment. No notation or comment was made by ABS and the vessel was put back into normal service. A critical OEM and class approved repair was executed. The Subsea Solutions Alliance yet again demonstrated how the impossible could be made possible through the close cooperation and development of critical underwater equipment repair procedures with our OEM partners. Let us know what we can do to support you!