Marine Engineering

The mechanical flexing couplings accept misalignment from rocking, rolling or sliding of metal surfaces. All metal mechanical flexing couplings require lubrication. Mechanical flexing couplings are: Gear coupling. Grid coupling. Roller chain coupling. Gear Couplings Gear couplings transmit the highest amount of torque and the highest amount of torque in the smallest diameter of any flexible coupling. Each coupling consists of two hubs with crowned external gear teeth. The hubs mesh with two internally splined flanged sleeves that are bolted together. Gear couplings accommodate angular and axial misalignment by the rocking and sliding of the crowned gear teeth against the mating sleeve teeth. Parallel misalignment is accommodated by having two adjacent hub/sleeve flex points. Gear couplings require periodic lubrication depending on the application. They are sensitive to lubrication failures but if properly installed and maintained, these couplings have a service life of...

Material flexing couplings typically do not require lubrication and operate in shear or compression and are able to accept angular, parallel and axial misalignment. Material flexing couplings are Jaw coupling,  Sleeve coupling,  Tire coupling,  Disc coupling,  Grid coupling and Diaphragm coupling Jaw Couplings The jaw coupling also known as spider coupling is a material flexing coupling that transmits torque through compression of an elastomeric spider insert placed between two intermeshing jaws. Flex element is commonly made of NBR, polyurethane, Hytrel or Bronze Accommodates misalignment Transmits torque Used for torsional dampening (vibration) Low torque, general purpose applications Sleeve Coupling The sleeve coupling transmits low to medium torque between connected equipment in shear through an elastomeric insert with male splines that mate with female hub splines. The insert material is typically EPDM, Neoprene or Hytrel...

An ‘Enclosed Space’ is defined as a space that has the following characteristics: Limited openings for entry and exit. Unfavorable natural ventilation. Not designed for continuous worker occupancy. Enclosed or confined spaces include, but are not limited to, cargo spaces, double bottoms, fuel tanks, ballast tanks, pump rooms, compressor rooms, cofferdams, void spaces, duct keels, inter barrier spaces, engine crankcases and sewage tanks. Although pump rooms come within the definition of an enclosed space, they have their own particular equipment, characteristics and risks which require special precautions and procedures. It is the responsibility of the ship’s operator to establish procedures for safe entry of personnel into an enclosed spaces. The process of requesting, raising, issuing and documenting permits to enter into an enclosed or confined  space should  be controlled by procedures in the ship’s  Safety Management System (SMS).  It is  the M...

Ozone depleting substances are man-made gases that destroy ozone once the gases reach the ozone layer. The ozone layer sits in the upper atmosphere and reduces the amount of harmful ultra violet radiation that reaches Earth from the sun.  Ultraviolet radiation can have detrimental effects on both humans and the environment such as inducing skin cancer and cataracts, distorting plant growth and damaging the marine environment . Ozone depleting substances include: chlorofluorocarbons (CFCs) hydrochlorofluorocarbons (HCFCs) hydrobromoflurocarbons (HBFCs) halons methyl bromide carbon tetrachloride methyl chloroform They have been used as: refrigerants in commercial, home and vehicle air conditioners and refrigerators foam blowing agents a component in electrical equipment industrial solvents solvents for cleaning (including dry cleaning) aerosol spray propellants fumigants.  According to MARPOL annex 6, requirement for control of emission from ships ...

The Flag State of a ship is the State under whose laws the vessel is registered or licensed. Flag State denotes the government whose flag the ship is entitled to fly. Normally a vessel will usually bear the flag of the country with which she has closest connections. Although other considerations such as commercial interestor in some cases the terms of a ship’s chartering  government contracts could determine the flag to be flown by a vessel. The Flag state has the authority and the  responsibility to enforce international  maritime regulations over vessels  registered under its flag, including  those relating to inspection, certification  and issuance of safety and pollution  prevention documents Flag States also have the responsibility  of implementing and enforcing rules  adopted by other inter governmental  bodies, including International Labour  Organization ( ILO)and International oil...

AIR BOTTLES :- Two or more air bottles of equal capacity are to be provided. With both the bottles completely pressed up, they should be able to give 12 starts of main engine, alternately in Ahead and Astern direction, without having to replenish them with air from compressors. This is in case of reversible engines. For non reversible engines, 6 starts should be possible under similar conditions. AIR COMPRESSORS :- Two or more main air compressors should have the capacity divided between them to fill up the air bottles starting from atmospheric pressure to required capacity within one hour. SAFETY DEVICES :- 1. Non return valve in starting air line, closest to main engine. 2. Pressure relieving device in starting air line, viz Bursting Disc. 3. Relief Valve in each Cylinder head of Main Engine. 4. Flame trap or flame arrestor in starting air line close to cylinder     head. 5. Means to prevent admission of starting air to cylinder already        ...

During sampling continuous drip samples to be taken from the vessel manifold by means of automatic sampling device in four containers of 1 litre capacity each.  These container are to be sealed and one to be forwarded to laboratory for analysis, one to be given to the fuel supplier, one to be kept as marpol sample and one to be kept on-board. If possible new bunker not to be used till test results of the bunker analysis is received. It is important that self test is carried out in the early stages of bunkering using fuel test kit provided on board. Ignition characteristic of the oil (CCAI) should be checked to ensure that the fuel complies with ISO standard 8217.Max. Allowable values are 1. Water content at viscosity 180/380=1%2. Density at 15 C=0.9913. CCAI value=850-875 or above.If any of the results are not within the range, bunkering to be stopped and ship manager, supplier to be informed.

All deck scuppers to be plugged after draining off any water accumulation on deck. Adequate save-all to be used while connecting or disconnecting bunker hoses. Check Bunker hoses for any damage. Attention to be paid to the tightness of the bunker hoses due to tidal effects. Communication and Emergency shut down signal between ship and shore to be established and fully understood. Tank vent pipes to be kept open to ensure escape of gases. Bunker Loading Plan or Chart to be prepared of the tanks in which bunkers are to be taken with present soundings and sounding at 85% of full capacity of the tank. No internal oil transfer to be carried out during bunkering operation. All unnecessary valves to be kept shut. Fire Fighting , pollution control and oil spill equipment to be kept ready. NO SMOKING SIGN TO BE DISPLAYED. Day / Night signal to be exhibited

These consist of hydro-dynamically based thrust augmentation devices also called as energy saving devices. These devices can be considered to be operating in three basic zones of the hull as follows i.   Located before the propeller. ii.  Located at the propeller. iii. Located after the propeller. Before the propeller 1. Pre-swirl Stator (PSS) It consists of a set of blades right in  front of the propeller. The aim is to  reduce the rotational losses in the  propeller slipstream by introducing a  rotation in the inflow to the propeller. PSS increases the hull efficiency and  hence the total propulsive efficiency.  DNV classification society has  reported a 6% power saving in design  draught but just about 1% in ballast  in a Kamsarmax bulk carrier that gives  indication of the potential of PSS for  the full form vessels. 2.  Becker Mewis Duct It is a Pre-swirl Stator with  Accelerat...

Anti-fouling Coatings Traditional antifouling type known as CDP (Controlled Depletion Polymer) is high rosin based that dissolves slowly in seawater. The useful lifetime of CDP paints is usually limited to 36 months. This can be extended by regular underwater scrubbing to remove the leached layer and rejuvenate the paint film but the effectiveness of such cleaning may be limited with respect to time. Two main high-performance polymer-based tin-free SPC (Self Polishing Co-polymers) technologies in current use are namely metal acrylate co-polymers and silyl acrylate co-polymers. The performance of certain current copper acrylate SPC products are understood to be at least equivalent to TBT-SPC products (TBT-SPC products are banned) that were in use prior to 2003.  While the above mentioned two types of antifouling coatings have biocides release properties, it can only be expected that the trend for increasing legislation in this area will eventually lead to removal ...

Below Procedure will come very handy for seafarers which have to deposits any particular fees for anything related to MMD's in India. As MMD's is going for all online transaction to ease up the process. And it might save your 100-200 Rupees which you will pay to the shops outside of MMD's if you dont know these things for on-line payment. If i got anything wrong, feel free to connect us at  https://meoexamz.com  and plz share this post as it might be useful for others also. Follow below steps for on-line transaction : 1. Open the NTRP site by: https://bharatkosh.gov.in/ 2. Choose Non-Registered Users.Also, you can register by Login, by creating ID and Password. 3. Select Depositors category as Individual or Autonomous body or PSU or Ministry, Department etc for Seafarers select Individual . 4. Click on Search button on  Purpose , in ministry select  Shipping  and Search. 5. Select Payment to your concerned M...

1.Any IC engine of cylinder diameter of 200 mm or a crankcase volume of 0.6 m3 and above shall be provide with crankcase relief valve of a suitable type with sufficient relief area. 2.In large engine, cylinder diameter more than 300mm, require one relief valve to be placed on each crankcase door. 3.In small engine, cylinder diameter not more than 300mm, crankcase door of which are usually very strong. It may have relief valve or valves at its end. 4.Its free area should not be smaller than 45cm2 and there shall be minimum of 115cm2 /m3 of the gross crankcase volume. 5.Spring setting for opening pressure is 0.07 bar at an internal pressure and will close when the pressure has been relieved. 6.The valves should open smartly and close positively and rapidly. 7. The relief valves shall be arranged or provided with means to ensure that discharge from them is so directed as to minimize the possibility of injury to personnel.

The incoming refrigerant temperature is low and chances of emerging hot spots is low. Crankcase forms the suction chamber of the compressor and chances exist that the compressor may draw in air and moisture. There is no O 2  available inside the crankcase of reefer plant which can lead to explosion.

It present the concept of an indicator for the energy efficiency of a ship It can be used to establish a consistent approach for voluntary use of an EEOI as its not mandatory. It will assist ship-owners/operators in the evaluation of the performance of their fleet with regard to CO2 emissions. Ship-owners are invited to implement either these Guidelines or an equivalent method in their environmental management systems. To provide assistance in the process of establishing a mechanism to achieve the limitation or reduction of greenhouse gas emissions from ships in operation. It present the concept of an indicator for the energy efficiency of a ship in operation, as an expression of efficiency expressed in the form of CO2 emitted per unit of transport work. These are intended to provide an example of a calculation method which could be used as an objective, performance-based approach to monitoring the efficiency of a ship’s operation. When using the EEOI as a performance indicator, the i...