Page 297 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

Block Diagram of Immersion Heater:

The direct heat transfer of this type of heater allows liquids to achieve the desired temperature rapidly. Heaters,
which are made of tubing bundles, can be fixed on the side of a container or submerged in its contents. Their
heating coils deliver heat to the contents of the container, which are distributed throughout the container.
Working Process Of Immersion Heater:
These heaters have an electrically resistant heating element encased in a sheath. When the heating element is
turned on, it heats its enclosing jacket, which in turn heats the sheath, which in turn heats the liquid. The conduc-
tivity of the jacket and sheath determines its effectiveness. There are two immersion heaters direct and indirect
that heat liquids in different ways.
Direct Immersion:
It is put directly into the liquid at the top or through a side fitting. Its heating element comes into touch with the to-
be-heated fluid. When it’s in place, it’s turned on, and electricity flows through the heating element into the liquid.
Indirect Immersion:
It is immersed in liquid after being placed into a pipe with a closed end. The heating element heats the air within
the pipe, resulting in an oven effect that heats the liquid. An indirect immersion has the advantage and purpose of
not coming into direct contact with the fluid, which prevents contamination and corrosion.
Moreover, the time required to heat a substance is determined by the quantity and power level of the heater. They
are intended to heat specific sorts of materials.
Parts of an Immersion Heater:
When examining an immersion heater, there are certain elements that have to be closely observed. They include:
Sheath material
Power density
Wattage
Enclosure
Temperature range
Heating element
Each of these factors are discussed below.
Sheath Material:
The most important consideration regarding the sheath is the material or fluid that will be in direct contact with
it since different sheath materials react differently to certain liquids. The chart below is a short guide regarding
sheath materials. Immersion heater manufacturers provide charts regarding sheathing regarding which ones are
appropriate for certain applications.

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CITS : E & H - Electronics Mechanic - Lesson 160 - 179