Pipeline
heating is a common requirement in many industrial processes across a broad
spectrum of industries, including petroleum, plastics, chemicals,
pharmaceuticals, power generation and food processing. Pipeline heating
applications, commonly referred to as heat tracer And Drum Heater systems, provide
heat both to prevent pipeline freezing and to replace process heat loss. Often,
electrical heating is the most practical and lowest cost way of achieving
pipeline heat tracing. Self-regulating heating cables produce heat from the flow of current through a polymeric heating element
located between two parallel copper wires. The heating element possesses a
positive change of resistance with temperature, thus limiting internal power
dissipation and preventing destruction due to self-heating. It is this
relationship between the heating element resistance and temperature that can be
used to control pipeline temperature in lieu of dedicated sensors such as thermostats
and thermocouples.
A self-regulating heating cable can be visualized as an array of parallel resistors with each individual resistor having a value inversely related to its temperature. As a result the measurement of pipeline temperature by sensing cable resistance produces a value averaged over the length of the cable being used. The averaging effect is a desirable feature when one considers that individual heating zones can exceed 200 feet in length, and that pipeline temperature will vary along its length due to variations in thermal losses caused by such effects as valves, pipe supports, damp insulation, etc. The problem of positioning a single external sensor in the correct location along a pipeline is thus avoided.
A self-regulating heating cable can be visualized as an array of parallel resistors with each individual resistor having a value inversely related to its temperature. As a result the measurement of pipeline temperature by sensing cable resistance produces a value averaged over the length of the cable being used. The averaging effect is a desirable feature when one considers that individual heating zones can exceed 200 feet in length, and that pipeline temperature will vary along its length due to variations in thermal losses caused by such effects as valves, pipe supports, damp insulation, etc. The problem of positioning a single external sensor in the correct location along a pipeline is thus avoided.
A
typical pipeline heating system consists of self-regulating cable strapped to
the upper quadrant of the pipe with both pipe and cable jacketed under a thick
insulating blanket to minimize thermal losses to the environment. The inside
diameter of the insulation should be larger than the pipe/cable diameter to
provide an air chamber which acts via convection to warm the pipe. In a steady
state condition the heat produced by the cable balances the heat which is lost
by the system to its ambient. The cable temperature must exceed the pipe
temperature if heat is to flow from cable to pipe. At equilibrium the heat
being lost to the environment equals the product of the thermal resistance (Ø)
and the heat energy produced per unit time or watts. In actual practice, the
user of self- regulating cable has the option of selecting wattage per foot
cable and low temperature or high temperature range operating characteristics. Shantinathsales
Is Best Drum Heater
Company In Delhi NCr.
Company Website:-
http://shantinathsales.in/product/drum-heater-jacket-barrel-heating-pad/
