Procedures to follow while installing heat tracing in pipeline
Installation shall be carried out under the supervision of a qualified person. Persons involved in the installation and testing of electric trace heating systems shall be suitably trained in all special techniques required, including the purpose and function of the electrical trace heating system, its associated power supply and control equipment, and how to recognize and avoid the hazards associated with its operation and maintenance. Heat tracing are done on the following:-
• Process Lines Complex Piping , Long Transfer Lines
• Tank Heating Vessel Heating ,Tank Foundation Heating , Hopper Heating
• Process Instrumentation Flow, Level and Pressure Transmitters , “CEMS” Continuous Emissions Monitoring Systems , Process Analytical Sample Lines
The above image illustrates how heat tracing is done.
Procedures to follow for installation:
At first temporary installation is done at the propose power supply.
Layout the heating circuit on the pipe allowing extra cable for the power connection and any splice connection. Do not exceed the heating cable with minimum bend radius of 10mm.
Next heating cable allowances are installed for valves, flanges, elbows and pipe supports.
Valves, pumps, and other miscellaneous equipment require additional passes of trace heater to offset the increased heat loss that occurs at these sites. Trace heaters are installed on valves or pumps using looping technique so that they can be removed for service and maintenance.
Finally keep the trace heater in secure contact with the pipe, using bands of attachment tape at least every 30 cm as shown in the figure below. Secure any required temperature sensors to the pipe using attachment tape.