Installation and precautions of electric heating cable for magnetic flap level gauge

　　In the cold winter, especially in the north, magnetic flap level gauges usually need to be heated and kept warm in actual applications to prevent the liquid in the pipe from freezing and ensure the normal operation of the instrument.

　　Among the heat tracing and heat preservation methods, there are steam, hot water tracing, electric tracing and other heat preservation methods to choose from. However, due to the characteristics of the electric heat tracing system, which is simple in structure, easy to use, high in thermal efficiency, safe and reliable, no pollution to the environment, long in service life and low in maintenance workload, the electric heat tracing technology is gradually replacing traditional heat preservation methods such as steam and hot water tracing and is widely adopted.

　　As an advanced heating system, whether electric heating can operate normally depends not only on the product quality and the scientific rationality of the selected design, but also on the correct installation method of the product. The following will focus on the installation of the electric heating cable for the magnetic flap level gauge and the precautions.

1. Installation of electric heating cable for magnetic flap level gauge

　　Heat tracing and heat preservation are generally carried out by bundling electric heating cables on the surface of the pipe to ensure that the liquid medium works at a certain temperature so that the level measurement of the easy-to-solidify and high-viscosity liquid medium can be carried out normally. There are generally two ways to install electric heating cables: spiral winding method and parallel laying method.

　　The electric heating tape for magnetic flap level gauges is mainly divided into single-piece electric heating tape and multiple-piece electric heating tape. The float of the magnetic flap level gauge is bundled with a magnetic flap and a display panel assembly. The magnetic flap is flipped by the magnetic coupling of the magnetic float in the float. In order to prevent the display panel from being far away from the float and affecting the flipping of the magnetic flap, the heating and insulation of the magnetic flap level gauge generally adopts a self-controlling electric heating tape, and adopts the method of parallel laying and multiple electric heating tapes to avoid the display panel for installation without affecting the heating effect.

2. Precautions for installing the electric heating cable of the magnetic flap level gauge

　　Generally speaking, the matters that need to be paid attention to when installing the electric heating cable of the magnetic flap level gauge are mainly the following:

　　1. During the construction operation, the electric heating tape is laid from one end of the buoy to the tail end, and then returned to the starting point for parallel laying, and the spacing between each heating tape shall not be less than 2 times the bandwidth.

　　2. Twisting should be minimized during installation, and the bending radius should not be less than 5 times the thickness of the heating tape. Generally, the heating tape should be fixed to the main pipe with glass fiber pressure-sensitive tape or aluminum foil tape every 50 cm to make the heating tape close to the buoy and improve the thermal conductivity.

　　3. It is strictly forbidden to use iron wire or plastic wire for binding. One end of the heating cable is connected to the power box, and the tail needs to be tightly sealed with a matching head. It is strictly forbidden to twist the two cables at the tail end.

　　4. The power cord should be a three-core cable, one of which is used as the grounding cable and is connected to the grounding terminal together with the heating cable shielding layer. The internal and external grounding bolts must be firm and reliable.

　　5. After the electric heating tape is installed, a layer of insulation needs to be added on its outer surface, and the insulation layer should be wrapped tightly with aluminum foil tape to reduce heat loss and improve the effect of electric heating.