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OIL TANKER

FAMILIARIZATION

COURSE.

INTRODUCTION TOSTATIC ELECTRICITY AND ITS

SOURCES:

A BRIEF DISCUSSION WITH

CAPT. VIRAF F. CHICHGAR

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STATIC ELECTRICITY - DEFINITION

Static electricity

The build-up of electric charge on the

surface of dissimilar objects. The staticcharges remain on an object until they

either bleed off to ground or are quickly

neutralized by a discharge.

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STATIC ELECTRICITY How is it created?

Materials are generally neutrally charged equal

number of electrons and protons.

However, some materials when rubbed/moved, have

a tendency to loose electrons quite easily.

They then develop a positive charge and the surface

they are rubbed on develop a negative charge.

When any positive / negatively charged material isbrought close to a neutral or opposite charged

surface, there can be a discharge ( due to the

difference in potential between both surfaces)

causing the phenomenon of static electricity.

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+

+

+

+

+

+

+

+

+

+- -

--

-

-

- -

-

-

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+

+

+

+

++- -

-

-

--

- -

-

-

+

+

+

+

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SOURCES OF STATIC ELECTRICITY ON SHIP.

To be discussed during this lecture:

OIL MOVING THROUGH PIPELINES

STATIC GENERATION DUE TO SPLASHING AND

SPRAYING

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OIL MOVING THROUGH PIPELINES.

1. Oil moving through a pipeline : frictional resistance

near the pipe wall and smooth movement near the

central axis of pipe.

2. This disturbed movement, along with impurities in

oil causes separation of molecules.

Stationary Oil droplet no

charge.

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OIL MOVING THROUGH PIPELINES.

1. The molecules then break up into charged particles, as

displayed in the diag. above. Electrons break free and

accumulate as negative charge on the sides of the pipe and

positively charged oil particles start accumulating within the

tank.

2. Once, the flow increases, build up of electron within the pipe

accumulates.3. Eventually the excessive negative charge built up within the

pipeline can be scooped an delivered into the tank where

positively charged oil already awaits- this can cause a static

electricity discharge.

+++++++VE - - - - - - -VE Positively charged oil movingthrough pipeline: -ve ions left

behind in pipe.

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WATCH THE CHARGES SEPERATE.

.

+++++++VE

- - - - - - -VE

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STATIC DUE TO SPLASHING/ SPRAYING

aa) Uncharged condition bb) Commencement of charge separation cc) Charged oil droplet

Tank

bulkhead Charge

developing

Charged

oil droplet

Tank

bulkhead

Tan

k

bulkhead

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STATIC DUE TO SPLASHING/ SPRAYING

aa) Uncharged condition bb) Commencement of charge separation cc) Charged oil droplet

Tank

bulkhead Charge

developing

Charged

oil droplet

Tank

bulkhead

Tan

k

bulkhead

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ANY QUESTIONS ?

THANK YOU FOR BEING ANATTENTIVE AUDIENCE.