Very high temperature furnaces

GENERAL DESCRIPTION:

High temperature chamber furnaces with maximum operating temperature of 1700°C. Constructed using a ventilated ‘heat box’ located in a welded steel framework with panels attractively finished in blue.

(Note: Furnaces with operating temperature of upto 1850°C can be constructed but they are very expensive and generally have a short service life. They are only made to special order.)

The furnace work chamber has a hard wearing removable hearth tile/s and is surrounded by a graded selection of the latest high efficiency, low thermal mass insulations, to minimise heat losses and to enhance a uniform working zone.

Heating is by means of free radiating molybdenum disilicide heating elements mounted vertically in recesses in the work chamber sides.

A manually (or optionally an electrically) operated up and over door provides for obstruction free access to the work chamber and keeps the hot face away from the operator at all times. The door holds a low thermal mass fibre door plug, and conceals the door linkages behind the fascia panel. A full width stainless steel shelf is fitted below the door.

Fans are fitted within the furnace casing giving forced cooling to the element terminals for increased life. The fans operate in conjunction with an internal case thermostat and also ensure that the control equipment and casing remains relatively cool at all times.

The furnace control system is mounted in a ventilated enclosure below the furnace body. The controls consist of a green illuminating on/off switch; a green ‘mains on’ neon; amber ‘load on’ neon; red ‘over-temperature cut out’ warning neon; digital over-temperature controller, and a digital PID fully automatic temperature controller.

Over-temperature protection is provided in the form of an independent adjustable digital temperature controller complete with its own thermocouple, and operates in conjunction with an overriding secondary contactor to offer a fail-safe back-up circuit.

Type B (Pt.30% Rh/Pt.6%Rh) thermocouples probe the furnace chamber for accurate temperature sensing for control and over-temperature protection purposes.

A door safety switch is fitted to all models, this operates in conjunction with a secondary contactor to provide isolation of power from the elements when the furnace door is opened. The over-temperature controller also works in this secondary circuit to complete the high standard of electrical specification.

The furnace heating elements are on low voltage provided by an integral transformer and power switching is by means of thyristors for accuracy and long life.

Various optional extras are available including: alternative models of temperature programmer; temperature recorder; time switch; chimney, and inert gas fitting etc.

Heating rates vary between models, for example RH1 0-1600°C. 10 minutes, RH4 0-1600°C. 30 minutes

Larger or non-standard furnaces can be manufactured to order.

Dimensions do not include door counterweights and movement.
Power requirements will depend on local conditions and usage.

The information and data herein are offered solely for your consideration and guidance and are not to be construed as a warranty or specification. Nothing contained herein is to be interpreted as authorisation to practice a patented invention without a licence.

ML Furnaces Limited