The enclosure protection is defined by the Ingress Protection (IP) Code where a two-figure number is used to indicate the degree of protection against the ingress of solids and liquids.
1.Drip-proof open ventilated motors are used where the risk of liquids leaking from overhead pipes and valves may be a problem.
2.Totally enclosed fan ventilated When a greater degree of protection is required the enclosure is made Totally Enclosed Fan Ventilated (TEFV) and jetproof. No external air is allowed inside the motor. To improve heat transfer the motor casing is finned to increase the surface area, and airflow across the fins is achieved by means of an external fan and cowl arrangement.
Motors located outside on weather decks have deck watertight enclosures but the external fan is omitted because of the possibility of ice formation.
3.Deck watertight motors (IP56) have sealed bearings and a watertight terminal box. They can be completely immersed in shallow water for short periods. Sealing washers are fitted under all screws and a coat of special corrosion resisting paint is generally applied to all external and internal surfaces
4.Deck motors for tankers must have a flameproof (Exd) enclosure if they are within 3m (4.5m for some ships) of an oil tank outlet
1.Drip-proof open ventilated motors are used where the risk of liquids leaking from overhead pipes and valves may be a problem.
2.Totally enclosed fan ventilated When a greater degree of protection is required the enclosure is made Totally Enclosed Fan Ventilated (TEFV) and jetproof. No external air is allowed inside the motor. To improve heat transfer the motor casing is finned to increase the surface area, and airflow across the fins is achieved by means of an external fan and cowl arrangement.
Motors located outside on weather decks have deck watertight enclosures but the external fan is omitted because of the possibility of ice formation.
3.Deck watertight motors (IP56) have sealed bearings and a watertight terminal box. They can be completely immersed in shallow water for short periods. Sealing washers are fitted under all screws and a coat of special corrosion resisting paint is generally applied to all external and internal surfaces
4.Deck motors for tankers must have a flameproof (Exd) enclosure if they are within 3m (4.5m for some ships) of an oil tank outlet
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