Steam Tracing
Steam tracing is heat tracing performed by circulating steam around process pipes to heat them
Steam tracing is normally installed on:
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Stagnant piping sections such as branch connections from parallel heat exchangers or pumps, bypasses around equipment. In such piping sections, condensation or solidification could occur. Steam tracing is used to avoid this.
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Equipment or piping that needs to be prevented from winterization due to low ambient temperature conditions, utilize steam tracing.
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Suction piping of a gas compressor from the outlet of the upstream KO drum can be equipped with steam tracing to ensure no condensation occurs which could damage the compressor.
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Inlet piping of relief valves has steam tracing to ensure the piping and valve interior is kept free of any solidified material or crystallized hydrates.
Purpose of Steam Tracing
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Keep the fluid inside to prevent solidifying due to wax separation, crystallization and water freezing.
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Maintain the fluidity of highly viscous products, e.g. no flow situations, shutdown, isolated lines, etc.
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To avoid fluid component separation due to low temperature.
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To prevent freezing of water-containing process fluid.
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To prevent corrosive compounds forming if condensation occurs.
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To prevent condensation of gaseous process fluids.
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To prevent cold brittleness of piping material.
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To prevent hydrate formation in pipelines due to low temperature.
A steam tracing system could be:
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A closed system, in which all condensate discharge from steam traps are collected for re-use or recovery.
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An open system, when approaches are not available or rare cases in which the condensate are discharged into a drain or atmospheric.
Types of Steam Tracing
Jacketed : used in ultra-critical applications, usually where a product temperature has to be maintained at an elevated temperature all of the time. The use of a steam jacket also allows quick pre-heating of the pipeline.
Critical : here, steam tracing is used to maintain the temperature of a product that will solidify or spoil should its temperature fall below a predetermined level.
Non-critical : tracing is used to maintain the product viscosity at its optimum pumping level.
Winterization : to ensure pipelines are not damaged due to freezing in adverse weather conditions.
Instrument : small bore steam tracing pipes, normally 10 mm, used to protect flowmeters, control valves, sampling stations, impulse lines etc.
Tube on pipe tracing arrangement
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Depending on heat mass, numbers of tube can be decided.
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Below figure A shows an example of one tube on pipe
Figure A
Jacketed Pipeline tracing arrangement
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Jacketed- used in ultra-critical applications, usually where a product temperature has to be maintained at an elevated temperature all of the time. The use of a steam jacket also allows quick pre-heating of the pipeline
Figure B
Schematic Arrangement of Steam & Condensate Circuit
