Flameproof motors (Ex) d:
Inflamable gases, vapours, fumes and coal dust are
a natural atmospheric hazards in coal mines, refineries,
petro -chemical industries, etc. NEWINDIA™ squirrel
cage motors are equipped with flameproof enclosures
for use in just such industrial application.
These motors can safely be used in Divisional Area
I where the expolsive mixture is present some times
in large quantities and where hazards may occur in
normal operating conditions. Relevant Indian Standerd
IS : 5572 defines these hazardous areas. The primary
objective of flameproof motors is to restrict the
propagation of fire hazards from affected media to
unaffected media. NEWINDIA™ flameproof motors
are employed to drive conveyors, coal cutters, loaders,etc.
in mines and for similar purpose in petro-chemical
industries. The motors comply with Indian Standard
Specification IS : 2148 for gas group I, IIA and IIB
and relevant British Standard Specification 4683 Part
2 for enclosures.They are also suitable for ignition
groups G4 and G5 as per VDE 0170/0171 or Temperature
Class T4 and T5 as per IS : 6381. Flameproof motors
up to 20HP 4 - pole are manufactured under licence
Navyug Electric Motors & Pumps Ltd. Corresponding
outputs in others poles can also be manufactured (
2-pole , 6-pole , 8-pole ) ( 180 , 200, 225 Frame
under development ).
Salient Features:
The flameproof enclosures consist
of sturdy cast iron parts which are mechanically robust
and very liberally designed. The cast iron enclousure
of the motors are built to withstand any internal explosion.
The gaps of joints and where the shaft passes through
the frame are so dimensioned as to prevent transmission
of igniting flame to the surrounding atmosphere. The
motors are so designed that the frame temperature will
remain below the ignition temperature of the gas-air
mixture involved. All cast iron parts forming the flameproof
enclosures are tested during hydraulic pressure test
at ( 16 kg./ cm .)for group IIB after final machining.
All the seats of joints are carefully machined to ensure
that permissible gaps are not exceeded.
Cable Entries:
Motors for mining applications are
provided with cable entries with compound filling sealing
boxes suitable for paper insulated lead covered double
wire armoured ("PILCDWA") cable. Cable entries
with FLP cable glands can also be provided to suit PVC
armoured mining cables.
Performance:
For performance , they comply with
Indian Standard Specification IS : 3682 for motors used
in underground mines and IS : 325 for other industrial
applications.
Approval Certificates:
All motors have been aproved by the
relevant authorities on the basis of test reports issued
by the Central Mining Research Station , Dhanbad. The
testing and certifying authorities for flameproof motors
are as follows :
Testing Authority:
The Central Mining Research Station
, Dhanbad
Certifying Authoroty:
The Director General of Mines Safety
, Dhanbad.
The chief Inspector of Explosives , Napur.
The Director General of Factory Advice Service and Labour
Instites , Bombay.
Performance Particulars of Flame Proof
Motors:
40 C Ambient, 415 V/+6% Voltage
fluctuation, 50Hz + 3% frequency fluctuation & Insulation
Class B.
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