Complex Piping Design Guide
This design guide addresses the heat tracing requirements of complex piping. Whether the application is a small project or a complete network of piping and equipment, designing an electric heat tracing system for complex piping is simplified by using self-regulating Thermon cables. The information contained in this design guide will take the reader through a step-by-step procedure to make proper heating cable selections based on:
• Pipe size
• Minimum ambient temperature
• Thermal insulation type and thickness
• Heating cable temperature start-up
• The Desired maintenance temperatu
• Available power supply
• Maximum exposure temperature
• Electrical area classification
After following the prescribed steps in this design guide, the reader will be able to design, select and/or specify or establish a bill of materials for a heat tracing system.
Typically, complex piping is located inside a process unit and consists of highly short runs of pipe with frequent tees, as well as in-line valves, pumps and related process equipment that also requires heat tracing. Circuit lengths can range from several feet (less than one meter) to several hundred feet (meters) in length; However, the average is usually 100 feet (30 meters) or less.
For applications ranging from protecting freeze water lines to maintaining elevated process temperatures high u.s. u.s. 300 ° F (149 ° C), TherMon self-regulating, cut-to-length, parallel resistance heating cables are recommended. Variations in the heat loss of the insulated pipe (due to equipment, supports and/or insulation) are compensated for by the heating cable's PTC (Positive Temperature's) last. Thermon offers heating cables specially designed, manufactured and approved to cover a wide range of applications.
BSX ™ . . . Designed forfreeze protection and temperature maintenance at or below 150 ° F (65 ° C),-the BSX is well suited for both metallic and nonmetallic piping and equipment.
RSX ™ 15-2 ... Designed for applications where the watt density requirements preclude the use of the standard range of BSX cables.
HTSX ™ . . . Designed for process temperature maintenance or freeze protection applications up to 250 ° F (121 ° C) temperatures and withstand intermittent exposure (power-on) up to 420 ° F (216 ° C), intermittent exposure to temperatures (power-off) up to 482 ° F (250 ° C) and continuous exposure (power-off) to 400 ° F (204 ° C). The cable is capable of withstanding the exposure temperatures associated with steam purging.
VSX ™ . . . Designed for process temperature maintenance or freeze protection applications up to 300 ° F (149 ° C) and withstand intermittent exposure temperatures (power-on) up to 450 ° F (232 ° C) intermittent exposure temperatures (power-off) up to 482 ° F (250 ° C) and continuous exposure (power-off) to 400 ° F (204 ° C).
Computer Aided Design Programs ... Thermon has developed a sophisticated yet easy-to-use computer program, CompuTrace ®, that provides detailed design and performance information. Users of CompuTrace are able to input application-specific information intothe program and obtain detailed electrical and thermal performance information. Calculations made within the program are based on the prescribed formulas in IEEE Standard 515-2004.
The information input to and/or generated from Compu-Trace can be printed and summary reports, including "load chart information, exported for use in other programs. While CompuTrace is a valuable asset to use in designing a heat tracing system, the design steps detailed in this guide will still fo