Pipe
a protective covering designed to help maintain an acceptable temperature for pipes and any substance flowing through the pipes
Critical thickness of insulation: The thickness up to which heat flow increases and after which heat flow decreases is termed as critical thickness. In the case of cylinders and spheres it is called critical radius.
Since the critical thickness is almost a few millimeters, it is seldom an issue for piping.
Different types of insulation: Hot using cotton, Cold using plastic, and Personal Protection for a temperature more than 60C.
Winterization:
To avoid winterization, 5C, (check stock and pour point)and protect pipe from winterization:
- Electric heat tracing: electric power to heat through resistor (like toaster)
Joule heating rule: P=I (Va-Vb):
I: Current traveling through the resistor P: Power converted from electrical to thermal energy
Heating mantel (Heizschale) is used to heat the pipeline electrically. After that, an isolation should be installed to prevent the heat loss.
2. Fluid heat tracing: through small pipe attached to the pipe being traced)
Cement can be used to provide an efficient thermal connection by eliminating air voids between the tracer and the process eq.
3. Insulation
4. Maintain a partial flow in sections of piping
5. Draining and flushing
6. Agitation
7. Antifreeze solutions such as hydrate formation inhibitor (molecules of light hydrocarbon, which is surrounded by water molecules/ dew point of gas/low temperature/ high pressure and composition of gas)
8. Hot air re-circulation for air coolers (check stock point)
Furnace:
In order to protect furnace body C-steel from very high temperature 1500C, fireclay(Schamotte) or Vermiculite is highly recommended
Leakage rate:
With Bernoulli equation, the leakage rate can be estimated. The following parameters are required for the estimation:
- Hole size
- Pressure before and after the hole
- Density of fluid through the hole
Pay attention to the total volume of pipeline regarding the leakage rate.
