The downside of these types of heaters is that if they are crossed over themselves they can overheat and burn out, they are provided in specific lengths and cannot be shortened in the field, also, a break anywhere along the line will result in a failure of the entire cable. It is powered at a specific voltage and the resistance heat of the wire creates heat.
#Heat cable series
Types Constant electric power "series" Ī series heating cable is made of a run of high-resistance wire, insulated and often enclosed in a protective jacket. However, care must be taken not to increase the vapour pressure of the fluid too much, as this would have a strong side effect on the available head, possibly outweighing any benefit. Therefore, the net positive suction head (pressure difference) available can be raised, decreasing the likelihood of cavitation when pumping. This is an effective means of slowly heating an object to measure thermodynamic properties such as thermal expansion.Īs heating a thick fluid decreases its viscosity, it reduces losses occurring in a pipe. They may use trace heating in conjunction with a variac, so as to control the heat energy delivered. In laboratories, researchers working in the field of materials science use trace heating to heat a sample isotropically.
#Heat cable install
Trace heating can also be done with steam, but this requires a source of steam and may be inconvenient to install and operate. Therefore, the pipeline must be provided with an external source of heat to prevent the pipe and the material inside it from cooling down. For example, wax is a material which starts to solidify below 70 ☌ which is usually far above the temperature of the surrounding air. Industrial applications for trace heating range from chemical industry, oil refineries, nuclear power plants, food factories. Hit-temperature trace heating elements can prevent blockage of pipes. Self-limiting or regulating heating tapes have been developed and are very successful in this application.Ī similar principle can be applied to process piping carrying fluids which may congeal at low temperatures, for example, tars or molten sulfur. The combination of trace heating and the correct thermal insulation for the operating ambient temperature maintains a thermal balance where the heat output from the trace heating matches the heat loss from the pipe. Hot water service piping can also be traced, so that a circulating system is not needed to provide hot water at outlets. ( December 2018) ( Learn how and when to remove this template message) Unsourced material may be challenged and removed. Please help improve this section by adding citations to reliable sources. Other uses of trace heating cables include: The most common pipe trace heating applications include: International standards applied in the design and installation of electric trace heating systems include IEEE standards 515 and 622, British standard BS 6351, and IEC standard 60208. One paper projected that between 20 trace heating would account for 100 megawatts of connected load, and that trace heating and insulation would account for up to CAD $700 million capital investment in the Alberta oil sands. Ĭontrol systems for trace heating systems developed from capillary filled-bulb thermostats and contactors in the 1970s to networked computerized controls in the 1990s, in large systems that require centralized control and monitoring. Self-limiting thermoplastic cables were marketed in 1971. Mineral-insulated resistance heating cable was introduced in the 1950s, and parallel-type heating cables that could be cut to length in the field became available. Mineral insulated cables ran at high current densities to produce heat, and control equipment was adapted from other applications. Development Įlectric trace heating began in the 1930s but initially no dedicated equipment was available. Electric trace heating cables are an alternative to steam trace heating where steam is unavailable or unwanted. Trace heating may be used to protect pipes from freezing, to maintain a constant flow temperature in hot water systems, or to maintain process temperatures for piping that must transport substances that solidify at ambient temperatures.
Heat generated by the element then maintains the temperature of the pipe.
The pipe is usually covered with thermal insulation to retain heat losses from the pipe. Trace heating takes the form of an electrical heating element run in physical contact along the length of a pipe. Įlectric heat tracing, heat tape or surface heating, is a system used to maintain or raise the temperature of pipes and vessels using heat tracing cables. Self-regulating heat tracing tape with the gray end seal next to a copper drain pipe with insulator wrapped around them.
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