Ship Repair & Conversion Report

Cascade General Gets Crystal Harmony Back In Sync

Subsequent to the departure of Holland America's Statendam in April, Cascade General took in Crystal Cruises' Crystal Harmony for a 10-day stopover in May. The 10-year-old ship underwent maintenance and overhaul work below its waterline, extensive interior remodeling and steel replacement for pool areas on Deck 11.

With maximization of work in mind, Cascade normally sends advanced crews to join cruise ships on their way to the yard's Portland, Ore. locale. This time though, the first mobile crew met the ship in Los Angeles, where work commenced immediately on an overhaul of one of Harmony's auxiliary boilers. A second team was then summoned to San Francisco to clean ballast tanks before undertaking structural repairs and preservation work.

easuring 790 ft. (240 m), the vessel was drydocked at Cascade's 982 ft. (299 m) Drydock four, beginning with the mechanical systems below the waterline. Sperry stabilizer fins, each weighing 27 tons were removed to a building bay for complete refurbishment, while the 1,000 kW Lips bowthrusters were taken out for complete disassembly, overhaul and testing in one of the shipyard machine shops.

Multiple layers of paint were blasted away to clean the hull down to its bare metal so that a five-coat Jotun paint system could be applied. Welding crews replaced corroded steel in several locations, and more than 50 sea valves were overhauled and inspections performed on propellers, shafting and rudders for Lloyd's Register compliance. Sri Lanka Diving Team Goes Beneath The Surface

Following the arrival of M/V Neptune Jasper at the Sri Lankan capitol and port city of Colombo, the vessel's crew spoke of a vibration that was occurring in the propeller shaft. Taking immediate action was the Colombo Engineering dive team who was summoned to examine the 20 ft. diameter prop. Using a JW Fisher DV-2 underwater camera system, the group was able to shoot an underwater video inspection that was then observed by an agent of Lloyd's Register of Shipping, who in turn discovered that one of the vessel's four propeller blades had been sheared off.

The JW Fisher camera allowed the shipping agent to perform an accurate assessment regarding the problem as well as the necessary repairs involved. Actions taken were that the propeller blade opposite the sheared propeller blade should be cut off to balance the rotation. Immediate action was necessary, as the drive shaft bearings would be severely damaged if left unrepaired.

Extensive oxy-arc underwater cutting on the required blade, which measured 97-in. with an 8-in. thickness. Working around-the-clock, the team was able to successfully complete the job despite obstacles as bad weather and underwater currents. Following this, M/V Neptune underwent sea trials where it was discovered that the vibration had been eliminated and the vessel was able to move on to its destination carrying its consignment of containers.

While the Fishers DV-2 camera is designed to used as a deep water drop camera, many commercial diving companies utilize the system as a diver-held camera.