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User should take care of two major points, if especially the recrystallized tube size is
larger than 60mms.
•
Programming should be applied to manage controlled heating to set temperature
and also controlled cooling is strongly recommended. Heat up rates of less than
8°C/min is strongly advised.
•
Always avoid removal of any substance within the tube while hot as this will create
a sudden cool down at point of contact. If absolutely necessary, use a insulating
sample carrier plate where the sample is placed upon during heating stage.
•
Intervention into the tube ,placing a sample while hot can also be a reason for
cracking, always use a carrier base plate
•
If relatively large samples are placed within the tube always take care for a slower
heat up to enable a stable heating.
5.
We recommend the use of furnaces with SiC heating elements without any shut downs,
kept at stand by at around 4000C when unoperational. This procedure will increase the
service life of SiC heating elements. Furnaces with wire heating do not require any such
precautions and can be turned off whenever required.
Whenever a breakage occurs of SiC elements, user has to change it in pairs, keeping the
unbroken one in stock. It is not possible to use an old SiC element together with a new
one.
The old unbroken element should be kept aside to be used in pairs with an old element.
At high temperatures a glassy phase coating appears on SiC elements. This coating
although not harmful to elements may fracture and disintegrate to small pieces of glass if
handled. For reasons of safety use a glove and eye glass while handling old SiC
elements.
6.
For PTF series furnaces of over 1400°C, a standard over temperature alarm system is
employed to protect the SiC elements. If ever over temperature increase occurs, this alarm
system cuts off the power by means of disengaging a contactor. This function is activated by
the small knob placed on the panel which has to be pressed at initial start ups.
So long as the power is not turned down repeated pressing is unnecessary as O/T
alarm system will always be active. Furnaces with this system will only start heating
when this knob is pressed. You will hear the sound of a contactor closing when the
knob is pressed.
7.
Keep organic solvents and water away from insulation material.
8.
Keep metal slag away from heating elements to avoid a short cut.
9.
Labnics furnaces are not designed for heating food and operator should not use the furnace
for cooking purposes.
10.
Heating elements usually give a long service life but are basically for consumption. They will
have to be replaced after a reasonable period of use. Heating elements are not a part of
Warranty which is provided for a period of 2 years.
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