Imperial Eastman
Immersion
Heaters
Applications
Pipe flange immersion heaters are designed for use in
pressurized vessel such as hot water and fuel oil storage
tan steam super heaters, hot water and ste boilers,
systems utilizing heat transfer oil reclaiming systems
and marine applications such as fuel, lube and hydraulic
oil heating.
Unique Construction Features
- Removable outlet boxes
provide free access to line terminals.
- Element spacers prevent hot spots.
- Permanent bus bars prevent less( connections.
- CSA Approval available on most items. (See
Special Feature 21.)
- Raised face flanges insure leaktight union with
mating flange.
- Lifting rings afford ease of handling.
- Large diameter elements provide extra electrical
insulation for better dielectric strength.
Engineering Design Information
Outlet Boxes-Removable NEMA 1 outlet boxes are
furnished on heaters with 3" through 8"
flanges, drawing up to 150 amps. A permanently mounted
plate contains electrical knockouts. The rest of the box
is secured with a single nut allowing easy removal and
access to line terminals.
On heaters with 10" and 12" flanges or
heaters drawing more than 150 amps, permanently attached
NEMA 1 outlet boxes with threaded hubs are provided
Element Spacers-Element spacers are
fabricated from material similar to the element sheath
and are pertorated to allow for maximum fluid flow
parallel to the elements. They prevent hot spots caused
by elements touching while maintaining the size and
rigidity of the heater bundle.
Spacers are provided on 24" maximum centers and
are secured in such a manner as to allow elements to
expand and contract freely.
Flanges-Raised face flanges carr
a nominal 150 # rating and are mad from forged steel or
mill certified ste plate to ANSI standards. Raised face
insures a leaktight gasketed union with mating flange.
Electrical Connections-Pipe flange
heaters are furnished with properly sized terminals and
candui openings to match the heater load, number of
circuits and operating temperature. Table 4 shows the
maximum amperage per circuit for various gauges of field
wiring brought to heaters having one through eight
circuits. Note: the maximum conduit size shown is
3".
Unless otherwise specified, heaters are furnished with
conduit openings and terminals suitable for a maximum
fluid temperature of 250' F. and the number of circuits
shown in the listing tables (pages 32 through 36).
Heaters ordered with additional circuits, of for higher
fluid temperatures will by furnished with conduit
openings and terminals to accommodate the wire gauges
shown in Table 4.
Occasionally low KW heaters operate from single phase
power. In this case, omit the 1.73 factor in the above
formula.
When a heater has more than eight circuits, or
requires field wiring that will not fit into a single
3" conduit multiple conduit openings will be
furnished. For example, a heater operating at 200' n with
six circuits drawing 70 amps each would be furnished with
two openings, each sized for 3" conduit. At 70 amps
and 200*F, 2/0 field wiring is required for three to
eight circuits.
Gasketing - A 1/16" thick gasket is
furnished as standard with each heater. The gasket is
sized to match the seating surface on the flange.
Spirotallic gaskets are also available. (See Special
Feature 12.)
Flange Temperature/ Pressure Ratings-Although pipe
flanges have nominal ratings, the actual pressure that
they will safely withstand is a function of temperature.
Table 5 below shows pressure ratings per ANSI Standard
1316.5.
Large Diameter Elements Elements measure .475
" 0. D., providing extra electrical insulation for
superior dielectric strength. As a result, elements are
suitable for line voltages up to 600 volts. At the same
time, uniform heat transfer from coil to sheath is
assured by compacting the insulation in high pressure
carbide rollers, then repressing all bends to insure
insulation integrity in this critical area. Copper
sheathed elements are silver soldered to the flange; all
other materials are welded.
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