Pipeline electric heat tracing and insulation is a new type of heating system, which can also be called a heating cable low-temperature heat tracing system. It is realized by converting electrical energy into heat energy. What is its principle? How to build it? These are all problems that we need to solve, so the editor has collected some knowledge about this aspect from the Internet, hoping to give readers some help and guidance. The introduction is as follows.
1. Working principle
The purpose of pipeline insulation and antifreeze is to supplement the heat loss caused by the temperature difference between the inside and outside of the pipeline shell. To achieve the purpose of anti-freezing and heat preservation of the pipeline, it is only necessary to provide the heat lost to the pipeline and maintain the heat balance of the fluid in the pipeline, so that its temperature can be maintained basically unchanged. The heat preservation and antifreeze system of heating cable pipeline is to provide the heat lost to the pipeline and maintain its temperature basically unchanged.
The pipeline electric heat tracing system consists of three parts: the heating cable power supply system, the pipeline anti-freezing cable heating system and the pipeline electric heat tracing intelligent control and alarm system. Each heating cable unit includes circuits such as thermostat, temperature sensor, air switch, AC over-limit alarm isolation transmission, heating cable disconnection monitor, working status display, fault buzzer alarm and transformer, etc. Adjust the working condition of electric heat tracing. Under working conditions, the temperature sensor is placed on the heated pipe, and its temperature can be measured at any time. According to the pre-set temperature, the thermostat compares with the temperature measured by the temperature sensor, isolates the transmission through the air switch in the heating cable control box and the AC current over-limit alarm, and cuts off and connects the power supply in time to achieve heating and anti-freezing. Purpose.
2. Construction
Construction mainly includes pre-construction preparation and installation.
1) Before installation, check the design drawings to confirm that the heating cables and accessories are fully equipped and consistent with the design. The installation of the piping system and acceptance has been completed, the accessories such as pipes and valves have been installed, and the pressure test and acceptance have been completed according to the relevant installation specifications. The anti-rust layer and anti-corrosion layer are brushed on the outside of the pipeline and completely dried. Check the outer surface of the pipe to confirm that there are no burrs and sharp angles to avoid damage to the cable during installation. The wall bushings for cables should be reserved at the wall where the pipes pass through. Check whether the installation position of the control box meets the design requirements. Coordinate with other professions to ensure that there is no conflict with other professions during the installation process.
2) Start the installation from the power connection point, the cable end should be thrown at the power connection point (do not connect the power first), and the cable between the pipe and the power supply should be connected with a metal hose. Place the two heating cables in a straight line along the pipeline, place the horizontal pipeline below the pipeline at an angle of 120 degrees, and place the vertical pipeline on both sides of the pipeline symmetrically, and fix it with aluminum foil tape every 3-50cm. If the heating cable cannot be placed under the pipe, the cable should be placed on both sides or the upper end of the pipe but the winding coefficient should be appropriately increased. Before placing the heating cable, measure the resistance value of each electric trace heating wire. After making sure that it is correct, wrap and tightly wrap the heating cables and pipes with aluminum foil tape to ensure that the surfaces of the cables and pipes are in close contact.
When placing the heating cable, there should be no dead knots and dead bends, and the sheath of the electric heating cable should not be damaged when piercing holes or pipes. The heating cable cannot be placed on the sharp edge of the pipe, and it is strictly forbidden to step on the heating cable and protect it. The minimum bending radius of the heating cable laying is 5 times the wire diameter, and there should be no cross contact and overlapping. The minimum distance between the two wires is 6cm. The local winding of the heating cable should not be too much, so as not to cause the pipeline to overheat and burn the heating cable. If more winding is necessary, the insulation thickness should be appropriately reduced.
The temperature sensor and monitoring probe should be placed at the lowest temperature point at the top of the pipe, closely attached to the outer wall of the pipe to be measured, fixed with aluminum foil tape and kept away from the heating cable and more than 1m away from the heating body. Shielded copper wire. In order to ensure the accuracy of the electric heat tracing temperature of the pipeline, it is necessary to calibrate the temperature sensor probe, and then install it with a special instrument on site. The probe should be installed in a hidden location to avoid damage. The temperature sensor and monitoring sensor should be placed in the insulation layer, and the connecting wire should be connected with a metal hose when it penetrates the pipeline to be detected.
Jiangsu Weineng Electric Co.,Ltd is profession manufacturer of various types of industrial electric heater, everything is customized in our factory, Should you have any questions please feel free to come back to us.
Contact: Lorena
Email: inter-market@wnheater.com
Mobile: 0086 153 6641 6606 (Wechat/Whatsapp ID)
Post time: May-26-2022