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Berghütten®

Cage elements

Cage-Elements consist of metallic parts and ceramic electrical insulating components as for example ceramic disks and the distance tubes between the disks. The metallic bar is necessary for the compound structure of the ceramic parts.

The holes in the ceramic disks are holding the heating elements in form of straightened heating wires, which are herewith electrically isolated held together. At one end there is a zone for isolation (made out of ceramic fibre) to get from the hot Zone a cold one where you can install the power leads. Normally this zone of isolation is made out of ceramic fibre but normal lightweight refractory bricks are also possible.
(At buyer’s option details of the construction are possible to realize.)

The heaters can made out of CeFeAl-alloys or NiCr-alloys. Caused by the atmosphere or the temperature it must be decided which alloy is the best for longer lifetime.
(Here the customer will get technical support from our experienced engineers.)

The cage-element from Berghütten has in comparison with others some characteristics as for example the ‘swimming’ ceramic support of the heater, which avoids by the the different expansion factors of the used materials an undesirable movement between the ceramic parts.

Application area:

Cage-elements can be used in horizontal position in connection with a radiant tube as well as in vertical position with or without a radiant tube. This must be decided for each application depending on the usage. Cage-elements are in the first line used in end-charge-and discharge-furnace, multipurpose chamber-furnace or in furnaces which have inside an aggressive atmosphere.

The maximum temperature of the heating wire is 1250 degree Celsius if using CrFeAl-alloys and 1150 degree Celsius using NiCr-alloys. Very good experiences are made with construction-lengths between 400 mm up to 2000 mm. But also other lengths are feasible using the necessary methods for the construction. The possible power is depending from the diameter of the cage-elements, from the length and used alloy and also from the needed temperature in the furnace.

Safety arrangements:

For protection against excess temperature of the heater we recommend one safety thermocouple-element for each cage-element or at least one for each heating zone.

Accessories:

For the horizontal installation of the cage-elements we can supply radiant tubes and heating alloys in different qualities which should be coordinated. We also are able to supply devices as connecting leads for high temperatures and support-blocks to guarantee a good installation.

With all that we can offer a solution for a quick and safe usage for the customer.

The diagram shows the maximal power of cage-elements per each meter lengths in dependency from the furnace temperature and the diameter of the cage-element (which is the diameter of the disks).

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