A cartridge heater is a cylindrical, high-performance heating element designed to be inserted into drilled holes for precise, localized heating. Commonly used in industrial applications, it’s ideal for heating metal parts from the inside. These heaters can be custom-built to specific watt densities, depending on your application needs.
Typical Lead Time: Our standard lead time for custom cartridge heaters is approximately 1 week.
Installation Fit
For low- to medium-temperature applications (up to 315°C), general-purpose drilled holes typically suffice. A slightly loose fit (around 0.23 mm to 0.36 mm oversize) makes installation and removal easier, especially for long heaters. However, in high-watt density setups, a tighter fit—achieved by drilling and reaming—is crucial for optimal heat transfer and prolonged heater life.
Operating Temperatures
Cartridge heaters can function across a range of watt densities, supporting temperatures up to 760°C. The actual temperature performance depends on factors such as:
Watt density, fit inside the hole, thermal conductivity of the heated material.
For high-temperature applications (above 540°C), Incoloy® sheaths are recommended for maximum durability and heat transfer efficiency.
Electrical Termination Considerations
At elevated temperatures, it’s essential to protect lead wires from heat exposure. Use heat-resistant terminals or design the cartridge so the lead wire area stays below its temperature limit.
Temperature Control & Sensing
Accurate temperature control is key to extending heater life, particularly in high watt density setups. Sensors should be positioned approximately 12.7 mm (½ inch) from the heater for accurate monitoring. While on/off control is widely used, it may cause large temperature fluctuations. For tighter control and longer heater lifespan, thyristor or proportional control systems are recommended.
Sensor Options:
Surface-mount thermocouples, RTDs, or thermistors
Bolt-on or magnetic-mount temperature sensors
Digital controllers with DC pulse output for proportional control through external relays
What to Specify When Ordering a Cartridge Heater
To ensure your custom cartridge heater is built to your exact specifications, please provide the following information:
Diameter (mm) – The outer diameter of the cartridge heater.
Length (mm) – The heated and overall length of the heater.
Voltage (V) – Operating voltage (e.g., 220V, 240V, etc.).
Power (W) – Required power rating or wattage.
Built-in Temperature Sensor (optional) – Specify if a thermocouple is required (Type J or K).
Additional Features or Requirements – Such as:
Mounting brackets
Threaded fittings or flanges
Lead wire length or type
Lead exit orientation
Screws, bushings, or any special installation accessories
Providing detailed specifications upfront helps us deliver a tailor-made heater quickly and accurately.