Importance of Marine Couplings
                     Importance 
Of Marine 
Couplings
Marine gearbox couplings are increasingly used for work boats, 
leisure vessels, and other industrial applications. They work by 
absorbing the shock caused by complex gear changes. They 
improve vibration isolation, minimise the load on the propeller 
Importance shaft seal and help reduce engine noise.
of Marine Maintaining and servicing your couplings is essential as they serve 
Couplings various functions to make your engine work properly. A proper mounting system, such as solid rubber, metal, hydraulic and 
polyurethane engine mount, is critical in maintaining the strength 
of the coupling and preventing vibrations from transmitting from 
the gearbox to the hull. 
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Eliminates Damage Caused by Propeller Thrust
Engine couplings improve alignment. They can be easily fitted and 
adjusted to the desired position. Additionally, most couplings are 
made from durable polyester elastomer to absorb the shock of 
Importance complex gear changes. 
of Marine Electrical Isolation
Couplings They are also designed to provide electrical isolation. Couplings are 
available in various stud sizes, ranging from three-stud to seven-
stud diameters. The flexibility of these couplings makes them 
suitable for most marine engines. They are also designed to reduce 
the impact of electrolysis.
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Prevents Misalignment of the Shaft
Spline coupling is a type of coupling with internal teeth that match 
Importance the externals of the spline shaft. This allows the coupling to be aligned to prevent misalignment of the shaft. This is often done 
of Marine when a ship has multiple engines. 
Couplings Gear couplings have a greater bending moment than spline and 
diaphragm couplings. This allows them to accommodate larger 
shafts and higher axial forces. These types of couplings are utilised 
on most marine gearboxes.
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Looking for a Coupling Replacement? 
Poly Flex offers flexible marine gearbox couplings that can be used 
on commercial and pleasure crafts. These couplings come in sizes 
Importance ranging from 3 stud diameters to 7 stud diameters and can be 
of Marine used with many different bellhousing sizes. 
The flexible disc is moulded from a special engineering polymer 
Couplings alloy and is highly resistant to salt water and petrol. These 
couplings are available with an SA5 Cobalt Zinc finish for maximum 
durability. They are also available with DNV Type Approval. Visit 
their website to learn more. 
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Importance 
Of Marine 
Couplings