UNDERWATER HULL CLEANING

Underwater hull cleaning is a proven cost saving tool for vessel operators. Fouled ship hulls increase the overall cost, causing increased fuel consumption and the emission of gaseous pollutants. The engines are strained as well as the propulsion system, the ship slows down.

FOULED SHIP HULL

One of the biggest problems facing the world shipping is fouled ships hulls. 1746 different species of marine organisms have been counted up, which are attached to submerged surfaces. Like shellfish, seaweed, sea moss and hydroids, which clog the underwater intakes, covering antifouling paint and creating a thick layer on the ship’s hull which in time destroys and affects its “good” function. Shellfish such as oysters and mussels, release millions of young bivalves in the water, which move with the help of the ocean currents. The young bivalves to enable to feed themselves adhere to static objects, which attract various species of algae. Ships that are anchored are ideal for the growth of these microorganisms. Typically, these are reduced when the ship is at sail, except for some that are very durable, such as the Brown Weed, which remain on the hull even when the ship is developing rapidly.

HYDRAULIC HULL CLEANING SYSTEM

The hydraulic hull cleaning Brush Kart System comprises of 3 units of brushes that retract fully from the hull with a clearance to prevent damage on the paint work coating while removing unwanted fouling and corrosion efficiently.

Another very resistant species are algae that secrete a sticky fluid which is highly corrosive, deriving from billions of algae monocytes, which produce syrupy nutritional means, which creates colonies, once installed they reproduce. Thus, a coating of the sticky liquid is created,as a thick layer which remains on the hull as the ship moves.

HIGH QUALITY UNDERWATER HULL CLEANING SERVICE

Kingshipping Trading rich activity of the underwater (uw) ship repairs is a glowing unique example of a speedy and healthy development in the maritime sector. Our Company has experienced and well trained diving staff in underwater repair and underwater maintenance of ship hulls. Moreover, we provide a whole range of wet services that ships require.

HIGH QUALITY UNDERWATER RUDDER REPAIR

 A rudder is the primary control instrument used to steer a vessel. A rudder operates by redirecting the fluid past the hull, thus imparting a turning motion to the vessel. In basic form, a rudder is nearly a flat smooth metal surface hinged at its forward edge to the sternpost. Early detection and repair of rudder damages can prevent future costly DD-repairs. Several defections can be observed on the rudder during an underwater inspection.

DETECTING INGRESS OF WATER

Ingress of sea water into rudder can reveal cracks. The buoyancy of the rudder is lost and extra weight can cause stretching on the pintles. Although no major casualty will occur, the internal parts might corrode. The cracks – holes should be repaired. The plug on the bottom of the rudder should be opened and water should be drained out.

DETECTING EXTREME NUMBERS DURING RUDDER CLEARANCE MEASUREMENTS

Neck bearing, pintle and jumping stopper clearance measurements provide an indication of the general condition of the rudder. Superintendents, class surveyors and naval architects can analyze the data and pinpoint the cause of the defection and give guidelines for the required repairs to the diving team.

DETECTING ABNORMALITIES ON THE RUDDER CARRIER OR ON THE RUDDER STOCK

Loose bolts, cracks or any other abnormalities on the weld joints of the rudder carrier with the hull or on the rudder plate. Early detection and repair can prevent the expansion of an existing problem. In some cases, permanent repairs can take place under the supervision of Class. Depending on the location of the damage, ballasting can provide a dry environment and permanent repair. Nondestructive measurements in and around the keyways of the fractures can be taken before the initiation of any repair.

TWIST ON THE RUDDER STOCK

Twisting is caused due to external force to the rudder plate either due to grounding, touching on rock or floating objects. During underwater inspection, a panoramic view of the rudder or the findings of a bending or excessive scratches on the rudder bottom may reveal twist on the rudder. If any strange behavior of the rudder is reported by the vessel’s officers, inspection may reveal a twist on the rudder. Usually if the angle of the twist is more than 10 degrees the rudder stock should be replaced. Underwater rudder replacement is examined on a case by case basis.

UNDERWATER INSPECTION REPORT

Rudder was found with corrosion.  One deep groove was observed on a welding seem on the port side of the rudder; Repairs took place according to AWS: A5.1:E6013 procedure sequence; which was performed by approved welder. Flat bottom, vertical sides and curves were found in good condition with no abnormalities on the shell plating, indentations or other abnormalities being observed. Bilge keels were found in good condition. No missing pieces, deformations or abnormalities of any nature were observed. Mewis duct was found with corrosion and pitting on the brackets from pressure side. Four bladed fixed propeller: Blade no2: found with minor bending approx. 2cm x 3cm blade no3: found with minor bending approx. 2cm x 5cm. On the bended tip , 2 cracks were observed. Minor pitting was observed on all blades. Vessel is using ICCP.  ICCP instruments were found in not working condition. Massive corrosion was observed on the submerged hull. Sea chest gratings were found in position with bolts and nuts with securing arrangement.We provide high quality underwater hull cleaning services (uw hull cleaning)

DETECTION CORROSION / EROSION

 

Due to the lack of cathodic protection corrosion may lead to extreme pitting and deep fractures on the rudder plate. Installing anodes and repairing the defected areas can solve the problem. In cases with excessive corrosion, class surveyors and superintendents should provide the diving team with the required repair plan.

CASE STUDIES

Rudder repairs, In water class survey, removal of entanglements from tail-shaft photos of operations

OBJECTIVES

The main objective of Kingshipping Trading is the continuous enhancement and development of money saving choices that it ensures its customers. Towards this direction, the most effective solution in saving money is the underwater hull cleaning. “Clean ship’s Hull means, reduction of fuel consumption, reduction of CO2 emissions, increase of ships speed.” “Fouled ship hulls increase the overall cost, causing increased fuel consumption and the emission of gaseous pollutants. The engines are strained as well as the propulsion system, the ship slows down