1. The electric heating tube is made of a metal tube as the outer shell, with an alloy heating wire as the heating element. At one or both ends, there is a lead out rod (wire) filled with magnesium oxide insulation medium inside the metal tube to fix the heating element of the heating element.
2. Lead out rod: a metal conductive component connected to a heating element, used for connecting components to a power source, and components to components.
3. Unfolded length (L), mm: The sum of the straight and curved lengths of the metal tube on the component drawing.
4. Heating length (t), mm: The length of the heating element arranged on the component drawing.
5. Heating surface area, cm square: The surface area of the metal tube on the heating length.
6. Surface load, W/cm square: The power per unit area on a heating surface.
7. Adequate heating conditions: The working conditions that enable the component to reach the specified working state.
8. Rated voltage, V: refers to the voltage specified in the design and marked on the component casing when connected to the component.
9. Rated power, kW: refers to the input power of the component specified and marked on the component casing during design.
10. Working voltage, V for a single component connected to the power supply, refers to the voltage specified in the design when connected to the component, that is, the rated voltage; For a group of components connected in series to a power supply, it refers to the voltage specified in the design to be connected to this group of components.
11. Working temperature, ℃: The average temperature of the heating surface of the component under rated power and sufficient heating conditions.
12. Maximum temperature: The temperature at the highest temperature point on the heating length of the component under 1.27 times the rated power and sufficient heating conditions.
13. Simulation conditions: The working conditions under which measures are taken to ensure that the operating temperature of the component basically matches the specified value under the conditions of each clause of the standard.
14. Allow repairs
Repair refers to the repair of damaged lead out rods, metal surface coatings, insulators, and seals, without affecting the performance and normal use of the components.
15. Recovery
Due to usage and long-term storage, the electrical insulation performance of the component is lower than the standard value. The process of restoring its electrical insulation performance to the standard value through methods such as oven drying, without affecting the performance and normal use of the component.
16. Damage
a. The withstand voltage of the component is lower than the standard value, the leakage current is greater than 5mA, or the insulation current is lower than 1M Ω, and it cannot be restored;
b. The shell has flame emission and molten material, severe surface corrosion or other damage that cannot be repaired;
c. The actual power of the component exceeds the rated power by 20%