Welcome to Swift heat & control

General information

Swift high watt density cartridge heaters are a futher development of the brass and steel jacketed cartridge heaters and tubular heaters. They are electric heaters which, where space is limited, will provide a relatively large heat requirement. They are specially suitable for use in moulds and tools for plastic processing particularly with hot runner systems, packaging machinery and the casting industry e.g. pressure die cast forms. They are designed for use up to maximum operating temperatures of 750°C and have a reputation for giving a long working life fully appreciated by designers and users. The preperation of the type list took into consideration market requirements so that export of tooling, machines and instruments fitted with Swift cartridge heaters does not create problems.

Standard Construction

a-Gas tight welded tip
b-Highly compressed insulating material MgO
c-Highcapacity heat conductor CN 8020
d-Sheath manufactured from Chrome-Nickel
..Steel No 1.4541

e-Ceramic coil former
f-Glass silk insulation emerging from the
...inside the cartridge heater (suitable forup to
...250°C)
g-Pure nickel connecting leads, approx.
...length 40mm

1/4' and 6.5mm diameter Swift heaters are supplied as standard with 250mm long flexible wire leads emerging from the inside of the cartridge heater.

Diameters: 4.5/6/6.5/8/10/11/12/12.5/16/19/20 are the equivalent of imperial sizes.
Length tolerance: ±1.5% minimum ±1mm
Diameter tolerance: Metric sizes - 0.02 - 0.06mm, Imperial sizes ±0.02mm of actual diameter
Unheated zone: On both sides 5-10mm dependant on diameter
Rating tolerances: ±10% of Ohm value
Every heater is tested for the following:
Diameter tolerance/Length tolerance/Resistance (Ohm value)/High Voltage stabilaty at 1500V
Insulation resistance (cold): 5 M ohms min @ 500 V
Discharge current (cold): less than 0.1 mA at 242 V

Options available
o tighter diameter tolerance
o deviations from nominal diameter up to ± 0.5mm dependant on diameter
o length of cartridge heaters on request but dependant on required wattages
o different voltages and wattages
o various types of leads and connections to suit applications.

Swift cartridge heaters are available with built-in Thermocouples, which enables exact temperature sensing especially where space is restricted.

The selection of sensor depends on the required operating temperature, or existing temperature controller.

Available sensors are

J-Iron/Constantan - up to ±300°C
K-Nickel/Chromium-nickel - up to ±750°C

Las 1-Lenth of thermocouple lead
Las 2-Fibre glass flexible stranded nickel leads
d-Diameter
L-Lenth
e-Flat or conical end disc for better conductivity and sensing.

In the case of the sensor measuring point (a) the rating is increased towards the base with these cartridge heaters. Also, with the sensor in this position at the bottom of the cartridge (normaly concave) is made flat, to improve the accuracy of the sensor. Note that it is important that the seat is correctly and accurately bored to allow the cartridge to "bottom".
Note also that the response of these heaters is very fast and the use of a simple on/off switch will result in fast ageing and a short life span. Energy regulators, or temperature controllers with built-in energy regulators should always be used.

Notes for fitting

o The service life depends on the correct dimensions and rating of the cartridge heater together
..with the correct temperature controller.
o For compacted cartridge heaters up to 20W/cm(square) surface loading the hole should be an
..ISA H 7 fit, and should have a smooth finish.
o With cartridge heaters having a surface loading exceeding 20W/cm(square) a slide or press fit
..should be aimed at using a 2-part design of the hole.
o Assembly spray, resistant up to 1200°C, aids assembly and especially removal.
o Assembly can be simplified by using through holes(possibly offset).
o The connection area of the cartridge heater or the tool should be free from liquids shuch as
..assembly spray, oil, molten plastic etc. Contact with liquids in this area will cause a short
..circuit, liquids must also not be allowed to penetrate through the bottom of the cartridge
..heater.
o The distance between cartridge heaters should be at least 1,5 times the diameter of the
..heater and 1 times the diameter between the heater and outside edge.

A NFG Tails Crimped to Studs

B Galvanised Sprague Tubing

C NFG Tail at 90°

D Sprague Tubing

E Ceramic Beaded Tails

F Stainless Steel Sprague Tubing

N Threaded Studs or NFG Tails each end

O NFG Tails (Flexible from within the cartridge)

Solid pin/multi-stranded connecting wires

Pure nickel pins/stranded wires are used as the connection wire for temperatures exceeding
400°C. Generaly the wire is insulated from the inside to the outside with a glass fibre sleeving.
With cartridge heaters of a diameter of 6.5mm the multi stranded wire is 250mm long and passes from the inside to the outside of the cartridge heater and is already insulated.

Heating conductor

The heating conductor is the actual heating element that converts the electrical energy to heat enery. It is therefore subject to the greatest physical stress. Consequently taking into account even the smallest change in resistance at different temperatures only iron free austenitic Nickel-Chrome-alloy NiCr 8020 (tested to Din 17470) can be used.

Composition

Designation according to DIN 17470	Main components in % by weight	Mould temp.	Density	Specific resistance at 20°C	Structure
NiCr 8020	Ni=77-80 Cr~19-21	1400°C	8,3	1,12	austenitic