Heater Cartridge
תכונות :
● Max Sheath Temperature 800°C (Depend of sheath material)
● 6V ~ 480V Voltages
● Dia.3mm to 30mm
● High Purity MGO
● Glass filament blanket
● 12” standard lead wire length
● Crimped On Lead & Swaged In Lead
● Custom design or built in thermocouples are available
בַּקָשָׁה :
● Semiconductor chamber heating
● Semiconductor wire & die bonding
● Humidity Control
● Patient comfort heating used in medical devices
● Mold die and platen heating
● Seal bars used in packaging equipment
● Test sample heating in gas chromatography equipment
Construction of a cartridge heater may be divided in 6 main parts:
1.Heating coil
The heating coil is the actual resistance which is where the electrical load occurs. The most common type of metal alloy used for this purpose is a nickel-chromium mixture, also known as nichrome. The nichrome wire is wound around a ceramic core, and the number of spirals per inch vary according to the requested watt density. Potential from an alternating current source, which can either be 2 phase or 3 phase, flows through the coiled nichrome wire, heating up the wire, which in turn, heats the cartridge heater sheath.
2.Insulation
Insulation is used to prevent the nichrome coil contacting the sheath, an event that would ground the resistance and could produce a catastrophic short-circuit, resulting in a melted sheath and a major equipment failure. Damage can be mitigated by installing a ground fault interrupting circuit. To prevent the coil from touching the sheath, the coil is inserted into the sheath, and immediately filled with magnesium oxide (MgO). To ensure the MgO fills the empty space between the sheath and the coil, the cartridge heater is filled under vibration.
3.Sheath
The sheath is the part of the cartridge heater which makes contact with the material or substance to be heated. Several metal alloys are used, depending on the type of application, such as highly acidic or corrosive environments. The most common types of sheaths are 304 stainless steel, 316 stainless steel, and incoloy 800. Incoloy has the highest temperature rating, and is considered a superalloy.
4.Sealing
After the cartridge heater has been filled with MgO, a seal is applied to the open end of the cartridge heater (where the nichrome coil was introduced). This prevents the coil and the MgO from coming out, as well as preventing contaminants such as plastic debris, air, or moisture from entering the heater.
5.Termination
Since cartridge heaters are installed in a wide variety of machines, manufacturers must design the heaters to meet certain
