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Heaters, Sensors, Controllers, Relays, Linear Displacement, and Leadwire

Miniature Cartridge Heater Manufacturer

1/8″ diameter, 5/32″ diameter, 3/16″ diameter, 4mm diameter

Standard Lead Times


MPI Morheat has an extensive Stock List of Cartridge heaters available for same day shipment. MPI Morheat also manufactures custom cartridge heaters and can expedite production if needed.

Cartridge heaters are most frequently used for heating metal parts through insertion into drilled holes. For easy installation, the heaters are made slightly undersized relative to their nominal diameter. The majority of applications do not require maximum watt/in². Using as little wattage as possible to meet process requirements will ensure maximum heater life.

Holes should be drilled and reamed, rather than drilled to the final diameter with a general purpose drill. At high watt densities, a close fit is important. The fit is the difference between the minimum diameter of the heater and maximum diameter of the hole.

The standard sheath material is 304 Stainless Steel which provides good thermal conductivity and resistance to corrosion and scaling. The welded end disc made from the same material as the sheath provides a positive seal against moisture and other contaminants. Grade “A” Nickel-Chrome resistance wire precisely wound on a high purity magnesium oxide core places the resistance wire as close to the inside of the sheath as possible. A high purity Magnesium Oxide (MgO) powder is used to fill all remaining space inside the sheath. Heater is then swaged, which compacts the magnesium oxide grains into a solid mass.

The standard termination is a Teflon® plug with Teflon® leads (Type M3) with internally connected leads that provide flexibility and allow the leads to bend sharply as they exit the heater.

Nominal Diameter1/8″5/32″3/16″
Actual Diameter0.122″/3.1mm0.153″/3.89mm0.184″/4.67mm
Tolerance± .002″/.051mm
Min Length1.25″/31.8mm
Max Length12″/305mm
Length Tolerance (up to 3.5″L)± .3/32″/2.4mm
Length Tolerance (over 3.5″L)± .3% of Sheath Length
Electrical Ratings
Nominal Diameter1/8″5/32″3/16″
Maximum Voltage240
Maximum Amperage3
Maximum Wattage at 120V360
Maximum Wattage at 240V720
Wattage Tolerance+10,-15%
Resistance Tolerance+15,-10%

1. Welded Disc
2. Stainless steel tube in 304/316/321/INCOLOY
3. Ceramic disc insulator
4. Pure magnesium oxide
5. Nickel-chrome 80/20 heater wire
6. Ceramic core
7. Hard ceramic head
8. Lead Wire
9. Optional Potting Compound

PictureTypeMax TempNotes
MGT 1000°C1832°F / 1000°CFlexible, Not Waterproof
MGT 750°C1382°F / 750°CFlexible, Not Waterproof
Duraflex1022°F / 550°CFlexible, Not Waterproof
MGT842°F / 450°CFlexible, Not Waterproof
TGGT482°F / 250°CDurable, Flexible, Not Waterproof
Teflon500°F / 260°CAbrasion Resistant, Small OD, Waterproof
Silicone Rubber355°F / 180°CVery Flexible, Waterproof, Easy to Nick
SEW2392°F / 200°CVery Flexible, Fair Abrasion Resist, Waterproof
Terminations & options
Common Termination StylesPicture
Teflon End Seal & Plug
Fiberglass Leads Internally Connected
Leads with S/S Braid
Leads with S/S Armor
Bent Cartridge Heater
Locating Ring