Heating element should be used correctly, otherwise their function can not be fully utilized, but also bring some hidden dangers.
1. Reasonable geometric shape selection and reasonable design of tube surface load
The effective heating zone of the metal tubular electric heating element is actually a main parameter of the comprehensive design parameters when designing the electric heating power (heat surface of the pipe surface). This parameter should be selected reasonably, and the conformity should not be too large. The water pipe is generally about 10W/cm2. The diameter of the pipe is generally determined to be Φ8-12mm. Among them, Φ8mm can choose to meet a slightly larger one, while Φ12mm should be selected to meet a slightly smaller one. For the determination of geometric shape, it can be applied according to the manufacturer's own products.
2, the overall design is reliable
In addition to its own safety and reliability, the components should also be reliable for the supporting anti-dehydration (anti-dry) device (secondary protection device if necessary), otherwise the components will be blown, burned, and even explode after dehydration. The consequences are very serious. In addition, due to the large electric power of the boiler, the leakage current at the working temperature will also be large (some high-power boilers will reach >5 mA). Therefore, the supporting grounding wire must be reliable and good in contact.
3. In some boiler designs, the electric heating element passes through a section of the cylinder for about 150 mm in length to enter the boiler body for heating. During the operation of the electric boiler, the dirt in the water easily stays in the 150 mm cylinder; for a long time, these The dirt becomes muddy, and this part of the electric heating tube is tightly enclosed. If there is a heating wire in this part, the heat will not be transmitted and the wire will be easily broken. Therefore, the electric boiler tube and the fasteners are generally required to have a width of 200m. Non-heating area.
Possibility of repairing defective products in the production of electric heating elements
In general, after the electric heating element is made, it is found that the defective product is difficult to repair, but in practice, we found that some can be repaired.
1. What kinds of electric heating component defective products can be repaired:
When the heating element filler-magnesium powder has the following problems, the components become defective, and such heating elements have the possibility of repair.
A Magnesium powder has a good quality, and when it is modified, due to uneven stirring or other reasons, after the electric heating element is made, its tide resistance is low, about 100 MΩ, the component is placed in the air, the resistance will continuously drop, and the two ends are injected. Red ink, the ink can be sucked in, the two end of the tube is cut open, and the red ink is sucked into >2mm.
B Magnesium powder is slightly damaged during the processing of electric heating elements:
Such as oil Ting tube, water dispenser pipe two-end flange welding, water pipe end welding and pickling during the plating process, (hydrochloric acid, nitric acid) and plating solution immersed.
C Other cases: If the electric heating tube is not over-fired or has been passed after the pipe is made, but the temperature of the furnace is too low or the temperature has arrived, but the furnace time is too short.