Underwater Propeller Blade Straightening

(Press Release)
Wednesday, June 13, 2012

With all five blades of its propeller severely bent, a 290-meter container vessel needed a fast, on-site solution to restore the propeller’s balance and efficiency. Hydrex diver/technicians are trained to carry out repairs underwater in the shortest possible time frame and a team was therefore mobilized to the ship’s location in Diego Garcia in the British Indian Ocean Territory to perform a cold straightening of the blades.

After the equipment arrived at the vessel’s location, the divers installed a monitoring station on a workboat and made all the required preparations. The workboat was then positioned next to the vessel and the team leader went on board to discuss the details of the operation with the captain and the chief engineer of the ship and to go over the safety procedures.

Next the team started the underwater operation with a detailed underwater survey of the damaged propeller blades. Because fouling was present on the blades, the divers carried out a polishing to be able to inspect the blades for stress fractures and cracks. The inspection revealed that the five blades had suffered multiple deformations along the trailing edges and that there were stress fractures and nicks in the same areas. Cracks were also found up to 15 mm deep.

Part of the team started the repair part of the underwater operation with grinding work on the blades to remove the cracks. Once this was done the locations were smoothed to create a hydrodynamic profile on the trailing edges. Meanwhile, the rest of the team also entered the water and prepared the in-house developed hydraulic cold straightening machine for the straightening operation. The divers carefully positioned the machine over the bends of the trailing edges of the first blade and, in close communication with the team leader on the work boat, applied pressure to return the bent blade to its original state. This procedure was then successfully repeated for the other four blades.

When the divers had also completed all grinding and polishing repairs on all identified cracks and gouges of the blades, they made a full inspection of the newly modified condition of the blades for the attending ABS surveyor and the captain of the vessel. With all parties involved satisfied, the divers demobilized their equipment and returned home.

The operation restored the balance and the efficiency of the propeller. By carrying out the straightening on-site and underwater, Hydrex avoided a costly and time consuming drydock visit for the owner of the vessel. 

Maritime Today


The Maritime Industry's original and most viewed E-News Service

Maritime Reporter June 2016 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

People & Company News

“Twiggy” Baker Wins BWT Puerto Escondido Challenge

Grant “Twiggy” Baker (ZAF) claimed victory today at the Puerto Escondido Challenge, besting a field of 24 of the world’s best big wave surfers in towering 20-to-35

Winners of International Seafarers' Welfare Awards

The winners of ISWAN's International Seafarers' Welfare Awards 2016 were announced on 24th June at a high-profile ceremony held in Manila, the Philippines. The

Maritime Needs More Women Power

United Nations  International Maritime Organization (IMO) Secretary- General Ki Tack Lim pushed for the increased involvement of women in the seafaring industry

Ship Repair & Conversion

Turkey to Modernize Pakistan’s Subs

The Turkish defense firm Defense Technologies and Engineering (STM) won the tender to modernize Pakistan's submarines against its French competitor DCNS, reports Daily Sabah.

Turkey Launches F-513 TCG Burgazada

Turkish Navy’s third Milgem class corvette, the F-513 TCG Burgazada, created as part of the MILGEM project, was launched with a ceremony attended by Turkish President

SeaPro FourStroke Making Gains in the Commercial Market

Mercury Marine’s family of SeaPro FourStroke outboard engines is suited for high-hour applications and harsh environments, according to the manufacturer, who said

Casualties

Blue Angels Resume Schedule

The U.S. Navy Blue Angels will return to its 2016 demonstration schedule July 2-4 in Traverse City, Mich., Commander, Naval Air Forces announced. The Blue Angels temporarily stood down,

Indonesian Navy fires on Chinese boat, injures fisherman

An Indonesian naval vessel fired on a Chinese fishing boat on Friday, injuring one person, China's foreign ministry said, the countries' third reported confrontation

Amid Melting Arctic Ice, Kerry sees Looming Climate Catastrophe

Standing near Greenland's Jakobshavn glacier, the reputed source of the iceberg that sank the Titanic over a century ago, U.S Secretary of State John Kerry saw evidence of another looming catastrophe.

Underwater Engineering

UK First to Accept Marine Geoengineering Amendments

The United Kingdom has become the first State to formally accept the 2013 marine geoengineering amendments to the 1996 “London Protocol”, the treaty covering dumping of wastes at sea.

Orca Energy ESS to Power Fish Farm Support Vessel

Grovfjord Mek. Verksted AS (GMV) has selected Corvus Energy as the supplier of the lithium ion based energy storage system (ESS) for a fish farm support vessel called GMV ZERO.

Viscometer Helps Coating Process

Oxfordshire based Chiltern Connections specialist is a provider of conformal coating machines and associated solutions for a wide range of industrial customers.

 
 
Maritime Careers / Shipboard Positions Maritime Security Navigation Offshore Oil Pod Propulsion Port Authority Salvage Ship Electronics Ship Simulators Shipbuilding / Vessel Construction
rss | archive | history | articles | privacy | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.0990 sec (10 req/sec)