Plastic Processing Heating Element of Cartridge Heater with Metal
Screen Sleeve
Description:
A cartridge heater is a tube-shaped, heavy-duty, industrial joule
heating element electrical resistance used in the process heating
industry, usually custom manufactured to a specific watt density,
based on
its intended application. Highly compacted they reach a surface
watt density of up to 50 W/cm².
The cartridge heater may be divided in 7 main parts:
Heating Coil; Insulation; Sheath; Sealing; Termination; Lead Wire
Type; Watt Density
Insulation is used to prevent the Nichrome coil to contact the
sheath. If such event happened, it would ground the resistance and
potentially 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 vibratory filled.
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, it is considered a
Superalloy.
After the cartridge heater has been filled with MgO, a seal is
applied to the open end of the cartridge heater (where the Nicrome
coil was introduced), this prevents the coil and the MgO from
coming out. Also, it prevents contamination, such as plastic
debris, air, or moisture, to go inside the heater.
Since cartridge heaters are installed in a wide variety of
machines, manufacturers must design the heaters to meet certain
clearances.[5] [dead link] The cartridge heaters might be
terminated with the leads coming out straight, or in a right angle.
Also, manufacturer must be careful that the leads are not exposed
to temperatures higher than the maximum rating for the lead wire.
In order to prevent lead wire damage from temperature, movement or
contamination, the lead wire can be protected with metal conduit,
braided metal or silicone sleeves.
Depending on the clearance and the design of the machine where the
cartridge heater will be inserted, the type of wire used will vary.
Fiberglass is the commonly used for cartridge heaters and other
high temperature applications, such as automotive wiring harnesses
and industrial equipment. Other variants used are silicone
impregnated fiber glass and silicone rubber.
Specifications:
1. Resistance wire: NiCr20/80
2. Insulation: Magnesium Oxide Powder
3. Sheath material: stainless steel304,316,321,incoloy800,
incoloy840
4. Voltage supply:110v,220v,230v
5. Wattage supply:0.5kw-15kw optional
6. Wattage tolerance:+5%/-10%
7. Length tolerance:±5%
8. Water proof:IP65
9. Power source: electric
10. Thermocouple type :K/J
11. Diameter:6-25mm
12. Lead wire length:20-30cm
Applications
1. Seal Bars
2. Torpedo Heaters for injection molding
3. Injection molding manifolds
4. Mass Spectrometry
5. Rubber molding
6. Food production
7. Immersion Tank heating
8. HVAC Compressors
9. Fuel Cell
10. Semiconductor
11. Medical Devices
12. Sensor measurement devices
13. Extrusion
14. Die Casting
15. Hot melt adhesives
16. Heat Staking/ Hole Punch
17. Plastic welding
18. Fluid heating
