• View basket
  • Check Out
  • Home Page

Cartridge Heaters

Things to watch out for when changing suppliers of cartridge heaters. This page explains the differences between high and low watts density cartridge heaters and gives you an idea of the standard diameters that are available.  If you have an urgent need to purchase high watts density cartridge heaters then, the five page datasheet showing 517 standard specifications is an essential read. 

  • We can help to identify the specification of the heater backed up by many years of experience selling cartridge heaters to industry.
  • We are not a manufacturer but we have trading accounts with the all the top producers and stockists.  We know where to source the best “Fit-for-purpose” cartridge heaters. We do carry a small stock of high watts density cartridge heaters.
  • We sometimes import cartridge heaters and we export to customers located throughout the European Union.  We usually source from UK manufacturers as this enable us to be more competitive.
  • We receive resale discounts from our suppliers based on our level of business that enables us to offer a competitively prices.
  • We may be able to offer a replacement quicker than the original equipment supplier.
  • We can offer technical advice on how to improve heater life and good practise.
  • We endeavour to provide quotations within 24 hours from receipt of an accurate specification.
  • We can offer an onsite survey of cartridge heaters to simplify future ordering.
  • We keep a record of all heaters ordered to speed up repeat ordering process.
  • We use reputable courier service to ensure goods are delivered when we say they will be.

All stocked cartridge heaters (Or rod heaters as some peope like to call them) can be found in our webstore under product id Ca

High Watts Density Cartridge Heaters

The picture shows some cartridge heaters I had manufactured for a Werner & Pfleiderer (Stutgard) extruder.  These heaters were manufactured in the UK in 4 working weeks.

High Watts Density Cartridge Heaters
  • These heaters are available in the following imperial sizes. 1/4, 5/16, 3/8, 1/2, 5/8, 3/4, 1 inch.
  • They are also available in the following metric sizes, 6.5, 8, 10, 12.5, 16 and 20mm
  • These heaters have a swaged construction that compacts the insulation.
  • When heating a platen, mould, die or hot runner probe with high watts density cartridge heaters inserted into drilled holes, fit is an important factor in determining the life expectancy of the heater.  Fit is the difference betwen the minimum diameter of the cartridge heater and the maximum diameter of the hole.
  • It is common practise to drill and ream a hole that a cartridge heater is intended to fit into.
  • Many different designs of lead exit are available.  I may be able to offer advise on the most suitable type once I know more about your application.
  • These heaters are designed to operate at sheath temperature up to 760 °C / 1400 °F.  Heater lead wires and terminations are rated for much lower temperatures.
  • Typically these heaters are rated for 120 Vac or 240 Vac supply for UK applications & 230 Vac for European applications. Three phase heaters are also available. Heaters with distributed wattage (i.e. non uniform windings) are also available.
  • We can supply cartridge heaters with various internal wiring configurations. 
  • The standard manufacturing lead time for these heaters is 14 working days.  It can take longer to supply depending on the heater complexity.
  • Care should be taken when changing from one manufacturer to another as the manufacturing tolerances may be different. You could end up with a lose fit heater.
  • I can supply this type of heater on a breakdown service basis but I have to charge extra in this case.  I would have to consult with the factory to determine what is realistically achievable at the time of the enquiry.

High Watts Density Cartridge Heaters from Stock

  • Has your production machine stopped because your cartridge heaters are faulty?
  • Does your mould tool need cartridge heaters?
  • Do you need cartridge heaters in a hurry?
  • Do you want to reduce your maintenance expenditure on cartridge heaters?

If you answer YES to any of the above questions then you need to talk to us.  We can supply any of the 517 specifications of cartridge heaters, with 1 metre fibreglass / teflon leads (specifiy which lead type you require when ordering), shown in the pdf file attachment below to your premises in a couple of working days.

High watts density cartridge heaters from Stock (2456kb)

Cartridge heater with 2 pin plug on housing and locating flange

Cartridge heater with 2 pin plug and locating flange.

We have supplied high watts density cartridge heaters with 2 pin socket and a locating ring in the past for heating a screen changer on plastics extrusion equipment. The heater shown in the picture was 3/4 inch diameter x 123mm inserted length, 240 Vac, 800 watts with a 25mm diameter locating flange.  It takes 4 working weeks to manufacture this style of heater.

Double ended cartridge heater

Double Ended Cartridge Heaters.

We can supply cartridge heaters with a threaded terminal at each end. This makes them double ended. The terminals can have an M3 or M4 thread depending on the amperage of the heater. Higher amperage heaters will require M4 thread. These heaters have a 304 stainless steel sheath. I have supplied 3/8" diameter and 10mm diameter heaters in the past for packaging machine applications. Double ended cartridge heaters are available in all the standard diameters.

It normally takes four weeks manufacturing leadtime but we can supply quicker if you pay a premium. Please call our office to find out more.

Low Watts Density Cartridge Heaters
low watts density cartridge heaters
  • These heaters are available in the following imperial diameters. 3/16, 1/4, 3/8, 1/2, 5/8, 3/4, 7/8, 15/16, 1, 1 1/4 inches.
  • Alloy 304 stainless steel is used to provide high temperature strength, good thermal conductivity and resistance to oxidation upto 650°C / 1200°F.
  • This design of heater is less moisture resistant than the high watts density design.
  • The low watts density design are less expensive than the high watts density design.
  • Maximum watts density 4.6 - 7.0 watts/ cm². (40 - 45 watts / in²).  depending on heater size and operating temperature. 
  • The standard termination design for low watts density heaters is an internally connected flexible lead rated to 250°C / 482 °F.
  • Typically 3 to 4 working weeks to deliver. However it may be possible to produce low watts density cartridge heaters faster if you are prepared to pay a premium.
  • I usually produce a dimensioned drawing with a unique reference for my suppliers to be able to quote accurately. 

Resistance Heaters Ltd, 30 Norbury Close, Knutsford, Cheshire, England, WA16 8 JP

T:- +44 (0)1565 640956, E:- info@resistanceheaters.co.uk