Carbolite BLF 18/21 - Manual (Page 7)

BLF
MF23 – 3.11
7
3.7 Inverted Crucible Option
Take special care over safety considerations: ensure that there is a safe surface on which to place
the crucible when hot. If the process permits, avoid lowering the hearth when the chamber is hot.
Depending on the height of the work-piece, it may be necessary to hold the crucible up in the
chamber when placing the work piece on the hearth; ensure that appropriate tongs are available
before starting.
Clamp Option
This option assists the placing of the crucible over tall workpieces. The “clamp” is provided in the
form of a support shelf which can be fitted to a hinge on the case, and a pair of insulated tongs.
With the hearth lowered, place the support shelf on the hinge, and swing to the side. Use the tongs
to lift the crucible up into the chamber, swing the shelf to the centre, and lower the crucible.
Place the work-piece. Reverse the procedure above and carefully lower the crucible over the
workpiece. Remove the shelf before raising the hearth.
3.8 Element Protection Tube Option
The tubes utilised for element protection within the BLF range of furnaces are fragile and extreme
care should be taken when handling them.
Replacement Procedure
On the underside of the front cowl is a stainless steel mesh, which should be removed for access to
the underside of the furnace.
You will see three crescent shaped stainless steel brackets which will support the protection tube
once in place; these should be removed by loosening the two screws that each of them in place.
Care should be taken as insulation may fall if unsupported during the removal of the sections.
Once the insulation sections have been removed, pass the tube up through the hole in the bottom of
the furnace and locate within the recess of the furnace roof.
Once correctly located, re-fit the insulation sections and the corresponding brackets.
Re-fit the stainless steel mesh guard to the underside of the furnace.