This includes the selection of the power of the heating element and the quality of the outer tube.
The power design of electric heating is a comprehensive consideration of various factors, mainly based on the surface load of electric heating tube to calculate, and liquid heating and dry air heating tube on the surface load requirements are also different.
In general,
In the case of scale is not serious, the surface load of the electric heating tube is controlled below 10W/ C ㎡;
Air dry heating tube surface load control in 8W/ C square meters.
Of course, the final power design needs to be designed according to the specific situation. The above is a very conservative design, which requires accurate calculation. Welcome to contact us directly.
For the outer tube material selection of electric heating tube,
SUS 304 is used for non-acid and non-alkaline liquid heating or dry air heating at operating temperature below 300℃.
SUS 316L is used for weak acid and alkaline liquid.
SUS 316L+ coating for strong acid and strong base;
SUS 321 is used for air dry firing at operating temperature between 300℃ and 500℃.
SUS 310S is used for gas dry firing at temperatures between 500℃ and 800℃.
IQC phase inspection
Upon receipt of the electric heating tube, the quality control department shall inspect its electrical properties, including,
The outer tube inspection: the outer surface is intact, bright, the welding is firm, the welding joint is beautiful, the bend shape is well formed, symmetrical, the sealing silicone is uniform, and there is no glue impurities in the screw teeth.
Power, resistance is within the tolerance range, power (+5%, -10%), resistance value (+10%, -5%);
Insulation resistance shall be > 1000 m Ω;
Leakage current ≤0.5mA;
Water pressure test (under the pressure of 1.2MPa, the welding place of the heating pipe shall not have water leakage and water seepage, and the pressure holding time shall be 5 minutes)
Guarantee
Pay attention to record the service life of the electric heating element. If the supplier's warranty period is 1 year, the product can actually be used for 2 years, it shows that the product quality and the supplier are trustworthy.
On the contrary, if the product is actually used for half a year under reasonable circumstances, there will be a problem.The product is obviously of low quality.
Note: the electric heating tube can not be used against the rules, such as heating liquid, remember not to dry burning out of the liquid.
The electric heating element we need to do should conform to the design specification, the electrical performance is within the standard range and the service life should reach the standard
