Zubler VARIO PRESS 300, Руководство по эксплуатации

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6.
Important notes for the processing of Lithium Disilicate
VARIO PRESS 300. e
6.4 Investing
Pay attention to the attached brochure re-
garding the VARIO BALANCE dosing device.
■ The mixing bowl should be moist.
■ Choose the desired concentration
■ The components will be weighed in
the following order: Liquid, water then
powder
■ When the powder is being put into the
mixing bowl, start the timer.
■
With every investment the total set-
ting time is different
(e.g. Zubler Press-max 25min.)
■ To achieve repeatable results, all steps
should always be carried out in the
same way.
• For the same quantities, always
use the same mixing bowl.
• Using different size mixing bowls
will result in different expansion
results.
• Spatulate by hand (e.g. 10 sec.)
• Depending on the investment,
always choose the same mixing
program.
■ Using light vibration while pouring the
investment into the ring.
■
Seat the levelling top at an angle, to
avoid trapping air (blisters) at the
bottom of the ring.
■
While setting, place the filled ring in a
vibration-free place.
■
The setting time must be followed ex-
actly (e.g. 25 min for Zubler Press-Max)
6.5 Burnout furnace
Set burnout temperature to 850°C
■ Keep in mind that the distribution of
temperature depends on the volume
of the furnace chamber, the number
and position of the heating elements
and the number of the rings.
■ Maintain the burnout furnace accor-
ding to the manufacturer's instruc-
tions.
■
Check the temperatures on a regular
basis and calibrate when necessary
■ Pay attention to the correct position
of the ring inside the burnout furnace
(see schema of the burnout furnace)
■ Depending on the number of rings
inside the chamber, increase the hold
time by 15 minutes for each
additional ring.
■
When the door is opened the tempe-
rature in the burnout furnace declines
by up to 80°C, the effective holding
time starts only when the oven
reaches the set temperature
(e.g. at 850°C) for a
100g ring: minimum 45min.
200g ring: minimum 60min.
How to position rings in a burnout furnace
❶
The distance of the rings to the inside
walls and to each other must be at
least 2,5cm (1inch). This is shown in
the illustration as red zone 1.
➋
The door of the furnace makes a
homogeious distribution of heat
impossible. Therefore, the ring may
not be placed in the front third of the
furnace (for large furnaces, this
applies to one quarter of the front
area). This is shown in the illustrati-
on as red zone 2.
➌
Place the rings in the remaining area
of the furnace chamber left over from
points 1) and 2). This is shown in the
illustration as the green zone.
➍
To avoid the development of shades
among the rings, do not position
them in a strait line.
■
Remove the top and base of the ring
with a rotating movement.
■
Remove the investment ring from the
silicone ring former. Let the ring set
for a minimum of 1 minute to ensure
complete moisture evaporation before
placing it in the burnout furnace.
➍
➌
➋
❶