Immersion Heaters
Tubular Heaters
Finned Tubular Heaters
CalRod® Heaters
Mould Heaters
Duct Heaters
Tank Heaters
Cartridge Heaters
Band Heaters
Strip Heaters
Radiant Heaters
Temperature Controls
Thermocouples & RTD’S
Relays
Drum Heaters
Silicone Rubber Heaters
Technical Data
   
   

The construction of high temperature cartridge heaters positions a nickel-chrome resistance wire precision wound around a magnesium oxide core. It is inserted into a stainless or Incoloy tube locating the resistance wire close to the sheath. The core is centrally positioned within the tube and filled with magnesium oxide powder. Nickel pins pass through the centre of the core making contact with the resistance wire at both ends. The whole is assembly is highly compacted by a swaging operation and thus ensuring excellent heat transfer to the external sheath. This allows for operating temperatures to 1600ºF and high watt densities. One end of the heater is closed with a welded metal end-disc and wire leads exit at the opposite end which is typically closed with a lava seal. A variety of wire leads and lead protection options are available. Heaters can be supplied with internal thermocouples, mounting fittings and many other options.


DIAMETER

     
 
Imperial Sizes
NOMINAL DIAMETER ACTUAL DIAMETER
1/8”
¼”
5/16”
3/8”
½”
5/8”
¾”
1”

Tolerance – ±0.002
0.121”
0.246”
0.308”
0.371”
0.496”
0.621”
0.746”
0.996”
 
     
     
 
Metric Sizes
NOMINAL DIAMETER ACTUAL DIAMETER
6.0 mm
6.5 mm
8.0 mm
10.0 mm
12.0 mm
12.5 mm
16.0 mm
20.0 mm

Tolerance – ±0.05 mm
5.89 mm
6.4 mm
7.9 mm
9.91 mm
11.89 mm
12.4 mm
15.88 mm
19.9 mm
 
     


ELECTRICAL CONNECTIONS

     
 
Wiring Options
High Temperature Fiberglass
90 Degree High Temperature Fiberglass Leads – See options
Stainless Steel Braid Over Wire Leads
90 Degree Stainless Steel Braid Over Wire Leads – See options
Armor Cable Over Wire Leads
90 Degree Armor Cable Over Wire Leads – See options
Teflon with Teflon End Seal Wire Leads – See options
Silicone Rubber Wire Leads
Threaded Post Terminals – See options
Terminal Box – See options
 
     


THERMOCOUPLES

     
 
Built-In
Thermocouple
"K" calibration thermocouple for high limit protection or temperature control.

"J" calibration thermocouple for high limit protection or temperature control.
 
     


ZONED HEATING

     
 
Zoned or Distributed
Wattage
Cartridge Heaters can be designed with varying wattage densities along the length of the heater. This is common for sealing bars where increased heat is required at the ends. This option offers more or less heat where required to ensure even and uniform heating.
 
     


MOUNTING FITTINGS

     
 
Fittings
Welded and Brazed Fittings are offered in Brass, Steel and Stainless Steel. They are available in single ended and dual ended constructions. These are suitable for immersion into liquids. Custom fittings are available and are subject to quantity minimums.
 
     


MOUNTING BRACKETS

     
 
Brackets
Mounting Brackets are available in a variety of materials, sizes and configurations. They can be supplied with or without gaskets. These are typically custom made to match your mounting requirements, but we do offer some standard designs.
 
     


LEAD WIRE OPTIONS

Crimped-On Leads
A high temperature double crimp connects the MGT (450°C) leads to solid nickel pins. This construction is recommended for applications with elevated temperatures. Due to the rigid nickel pins, this construction is not recommended in applications where movement or flexing is encountered, or if sharp bends are required adjacent to the heater exit.

   

Swaged in Leads
High temperature MGT (450°C) wire is internally connected and swaged in place. This construction is recommended for applications in which the leads must be bent at the exit point from the heater and where mild flexing may be found. For applications with continuous or more severe movement, we would recommend metal braid or armor cable.

   

Stainless Steel Braid
High temperature MGT (450°C) wire is internally connected and swaged in place along with stainless steel braid. This construction offers protection against abrasion and sharp edges. This is a very strong construction which offers full length flexibility. This construction is recommended in applications with flexing and where the leads must pass through metal openings or routed along metal components.

   

Stainless Steel Armoured Cable (Hose)
High temperature MGT (450°C) wire is internally connected and swaged in place along with stainless steel hose. This construction is recommended for applications in which the leads are subjected to abrasion or run the risk of being pinched. This is the strongest lead protection available and works well in moving or flexing applications.

   

Right Angle Fibreglass Leads
High temperature MGT (450°C) leads exiting at right angle to the sheath. This construction offers a compact design where space is limited. This construction is not recommended where abrasion or flexing is present.

   

Right Angle Stainless Steel Braid
Stainless steel braid over high temperature MGT (450°C) wire exiting at right angle to the sheath. This construction is recommended in applications with flexing and where the leads must pass through metal openings or routed along metal components. This construction is desirable when space is limited and it is not feasible to bend standard leads.

   

Right Angel Stainless Steel Armour (Hose)
Stainless steel hose over high temperature MGT (450°C) wire exiting at right angle to the sheath. This is the strongest lead protection for use in applications where severe abrasion is present. These leads offer good flexibility and are good for moving or flexing applications.

 


FITTINGS & FLANGES






Single and Double Threaded Fittings
Single or double threaded fittings attached to sheath to allow for installation into threaded holes.

Fitting
- Brass, Steel and Stainless Steel Materials

Leadwires

- Fiberglass for high temperature applications
- Teflon for moisture protection
- Stainless Braid or Hose for flexing applications and abrasion protection

Terminal Boxes
- General purpose and moisture resistant housings.

 

Mounting Flanges
Mounting flanges are recommended for applications where vibration or movement may cause the heater to be disloged from its hole. Stainless steel flanges are available in a variety of sizes and configurations. The standard flange is round and is supplied with two mounting holes. For heaters 5/8" diameter and under, the flange would be 1 1/2" in diameter. For larger diameter heaters the standard flange would be 2.00" in diameter.

   


OPTIONAL CONSTRUCTIONS

Teflon End Seal
A Teflon plug is swaged in place along with Teflon leads. This construction resists oil and water to 250°C/480°F. There is a minimum of a 1.00" unheated length at the lead end. Longer cold sections may be required if the watt density or operating temperature is high.

   

Screw Terminals
Threaded stud terminals are supplied complete with high temperatue nuts and washers. Standard screw is #8-32. Available in 5/8", 3/4", 1", 16 mm and 20mm diameters heaters.

   





Double Ended Terminals
These terminations are ideal for applications where wiring form both ends is required. A minimum cold section of 1" is required for these leads.

Available Terminations

- Solid nickel pins
- Leadwires
- Threaded studs

   

Terminal Boxes
Terminal boxes are permanently attached to the heater sheath to provide excellent protection in a variety of environments.

Available Boxes
- General purpose sheet metal
- Moisture proof
- Cast aluminum explosion resistant

   


INTERNAL THERMOCOUPLES

Internal thermocouples are built into the heater assembly to monitor the internal or sheath temperatures. These are useful as high limit devices or in applications where space is at a premium. The power and sensor leads exit the sheath together and can be ordered with a variety of lead protections. Not all thermocouple configurations are available on smaller diameter heaters.

Type J and K calibrations are standard for the shown constructions.



Grounded at Disc End
The thermocouple junction is grounded to the disc end of the heater. This construction is commonly used in hot runner applications. The disc end can be filled with silver solder and ground flat. This will ensure good contact when inserted into a flat end blind hole.

   

Ungrounded at Disc End
The thermocouple junction is ungrounded and is located just behind the disc end. This will give a reference temperature of the part being heated.

   

Grounded at Centre
The thermocouple junction is grounded to the sheath along the length of the heater. The standard location is at the center of the heater, but can be located anywhere along the lenght of the sheath. This construction will provide a quick response.

   

Ungrounded at Centre
The thermocouple junction is ungrounded and is centered in the diameter of the sheath. The standard location is at the center of the heater, but can be located anywhere along the length of the sheath. Typically used as a high limit in air or vaccum applications.