MAINTENANCE
5.Maintenance
5.1 Introduction
With this system, maintenance is reduced to a minimum. It is only necessary on the rare
occasion when a part fails. Replacement of parts is described in the following paragraphs.
5.2 Heating Element Coil
• The heating element must be replaced by a new one, when it is out of order.
• Preceding the installation of a new heating element, remove the quartz tube and
thermocouples first (take it out of the furnace).
• After installation, beware of following the procedure, described in item 4.2 again.
Installation of a new heating element (exchange of the heating element) must be
done in the following order:
• Turn-off power to tube level (using the tube switch).
• Place safety marker on tube switch, preventing someone switching on again (meet
customers facility safety requirements).
• Close the ballvalves in the gassource cabinet at shelve (tube) level.
• Remove outer panel at tube level, by turning the DZUS-fasteners at the left- and
right side of the panel.
• Open 'tunnel' in front of heating element in which the thermocouple wires are
connected.
• Disconnect the clamp spring of the connected thermocouples.
• Disconnect the thermocouple wires from, these thermocouples.
• Withdraw carefully, using gloves, and place them at a safe and clean place to prevent
damage and remove the insulating cord (see Figure 4-3, page 4-5).
• Disconnect the gas inlet line to the process tube.
• Remove the frontflange assembly (only mounted for LPCVD) and when present,
also the backflange.
• Remove process tube from the furnace tube level (using gloves) and put it at a safe
and clean place.
• Remove tube adapters and the tube support.
• Remove the front support of the heating element, when necessarily.
• Disconnect the thermocouple-connection cables from the terminal blocks.
• Remove 'tunnel' from the thermocouples.
• Bend the compensation cables from the thermocouples carefully to the side.
FURNACE REFERENCE MANUAL
5-1