Electrical Apparatus Of Flameproof Type Of Explosion- Protected Construction; Terminology - GE FVP110 Maintenance Manual

GE Energy
Electrical Apparatus of Flameproof Type of Explosion- Protected
Construction
Electrical apparatus which is of flameproof construction is subjected to a type test and
certified by the Japanese Ministry of Labour aiming at preventing explosion caused by
electrical apparatus in a factory or any location where inflammable gases or vapors may
be present. The flameproof construction is of completely enclosed type and its enclosure
shall endure explosive pressures in cases where explosive gases or vapors entering the
enclosure cause explosion. In addition, the enclosure construction shall be such that
flame caused by explosion does not ignite gases or vapors outside the enclosure.
In this manual, the word flameproof is applied to the flameproof equipment combined with
the types of protection e, o, i, and d as well as flameproof equipment.

Terminology

Enclosure
Shroud
Enclosure internal
volume
Path length of joint
surface
Gaps between joint
surfaces
The permissible sizes of gaps between joint surfaces, the path
length of a joint surface and the number of joint threads are deter-
mined by such factors as the enclosure's internal volume, joint
and mating surface construction, and the explosion classification
of the specified gases and vapors.
An outer shell of an electrical apparatus, which encloses live
parts and thus is needed to configure explosion-protected con-
struction.
A component part designed so that the fastening of joint surfaces
cannot be loosened unless a special tool is used.
This is indicated by:— the total internal volume of the flameproof
enclosure minus the volume of the internal components essential
to equipment functions.
On a joint surface, the length of the shortest path through which
flame flows from the inside to outside of the flameproof enclosure.
This definition cannot be applied to threaded joints.
The physical distance between two mating surfaces, or differ-
ences in diameters if the mating surfaces are cylindrical.
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