Product Description;
Single Head Finned Heating Rod Origin:
Single Head Finned Heating Rod is made by filling a metal tube with high-resistance electric heating alloy wire as the heating material. It is filled and compacted around the heating wire, has good insulation performance, and uses high-purity magnesium oxide with high thermal conductivity as the filler. It has high power, high thermal efficiency, fast heat dissipation, etc., and can be used for plastic packaging, small mold heating, analytical instruments, and the refrigeration effect during the expansion of various gases.
Single Head Finned Heating Rod Selection Principles:
Temperature and corrosion resistance: For low-temperature tubes, BUNDY, aluminum tubes, or copper tubes are generally used; for high-temperature tubes, stainless steel tubes or Incoloy tubes are generally used. In cases of severe water quality,
Teflon heating tubes or stainless steel tubes with coating treatment can be used. Stainless steel tubes with coating treatment can be used under poor water quality conditions. Incoloy 840 heating tubes have good oxidation resistance at high working temperatures and good corrosion resistance. Generally, Incoloy code tubes are replaced by domestic 2520 material, which has the same effect.
Single Head Finned Heating Rod Performance Indicators:
1 Heating time: Under test voltage, the time for the component to rise from ambient temperature to test temperature should not exceed 15 minutes;
2 Rated power deviation: Under full heating conditions, the deviation of the rated power of the component should not exceed the following specified range: for components with rated power ≤100W: ±10%. For components with rated power >100W: +5% to -10% or 10W, whichever is greater;
3 Insulation resistance: At factory inspection, the cold insulation resistance should not be less than 50MΩ;
Single Head Finned Heating Rod Usage Precautions:
1. During use of high watt density single head heating tubes, due to rapid self-heating and poor heat dissipation conditions, the external stainless steel tube body often becomes blackened, oxidized, and deformed, causing the internal heating element - the electric heating alloy wire - to melt due to high temperature dry burning, shortening the life of the single head heating tube. Therefore, a good single head heating tube not only requires good production quality but also requires the mold material and machining hole diameter (the closer the hole diameter to the tube diameter, the better). A suitable hole diameter not only facilitates replacement of the single head heating tube but also benefits heat conduction between the two, thereby extending the service life of the heating tube itself.
2. Deep hole machining of the mold should pay attention to precision. Do not drill holes from both ends, because the junction cannot be tightly sealed and will have larger gaps, causing poor heat dissipation of the heating tube and uneven temperature of the heated body.
3. Pay attention to the magnesium oxide powder at the outlet end of the heating tube. It should not be exposed to pollutants and moisture in the usage site to prevent leakage. It is best to leave 5mm outside the mold.
4. When starting up the heating tube, it is best to preheat for 5 minutes to avoid leakage due to air humidity or moisture penetration into the tube. The heating machinery must be equipped with a grounding wire.
Selection of Magnesium Oxide Powder for Heating Tubes:
Magnesium oxide powder is located between the resistance wire and the tube wall, used for insulation between the resistance wire and the tube wall. At the same time, magnesium oxide powder has good thermal conductivity. However, magnesium oxide powder also has strong hygroscopicity, so it must undergo moisture-proof treatment (magnesium oxide powder modification or heating tube sealing treatment) before use.
Heating Tube Life
The life of the heating tube is not only related to the quality of the resistance wire but also to the quality of the magnesium oxide powder, the selection of the resistance wire diameter, and other factors. For high-temperature heating tubes, KAWAI can manufacture heating tubes with a surface load below 8W/cm². When selecting the diameter of the resistance wire, the surface load of the resistance wire must be calculated to meet the life requirements.
Environmental Conditions for Heating Tubes:
a. Altitude not exceeding 1000m
b. Ambient temperature -20~50℃
c. Relative humidity of surrounding air not greater than 90% (at ambient temperature of 25℃)
d. No conductive dust, explosive gases, or corrosive gases that can seriously damage metals and insulating materials in the surroundings
e. No significant impact or vibration
Heating Tube Cracking:
(1) The weld quality of the stainless steel tube is particularly poor, and the tensile strength is too low;
(2) For new tubes, the drying process is not done well, and the moisture in the magnesium oxide expands rapidly due to heat, exerting large pressure on the tube wall.
(3) Prolonged non-use in high humidity, allowing significant moisture intrusion into the tube
VerificationElectric Heating Tube The Most Intuitive Method to Judge Quality
First, wipe the surface of the heating tube clean, then connect to AC 220V power supply, dry burn in air, disconnect after the surface turns red, wait for the heating tube to cool completely, then wipe with a napkin. There should be no black oxide powder (unreacted with oxygen in the air) on the white paper, indicating that the heating tube is of high quality.
Electric Heating Tube Design
