3D Systems sPro, User Manual

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SLS p r o c e s s 1 6 6 I R S & I P C
u s e r ’ s g u i d e b l e n d i n g
B l e n d i n g
When the Blender drops below approx. 20 kg, it
will attempt to blend a batch of powder. Blending
will not start until a sufficient quantity of both
Used and Virgin powder is available as measured
by the load cells supporting the Used and Virgin
powder bins. Once this has been checked and
satisfied, the IRS will begin blending by
transferring a load of whichever powder makes
up the majority of the batch.
Following this, at the end of each transfer
(whether of Virgin or Used powder) the IRS
calculates the current percent virgin based on
weights transferred so far.
If the percent of virgin is...
`
above the final desired percent virgin (user
settable at the UI on the IRS) it transfers a
load of used powder.
`
below the final desired percent virgin, it
transfers a load of virgin. The weight of
powder transferred with each load varies
somewhat and it is different between the
used and virgin bin due to the slightly
different flow properties of each material.
In addition, the desired ratio of virgin to used
powder may not be 1:1. Therefore, the powder
proportioning does not always alternate one load
of each. At the end of the proportioning, the last
load may be greater than the final weight of
powder needed to arrive at the percent Virgin
needed for the entire batch. Therefore, it transfers
only the required weight to the blender and
returns the excess powder in the transporter to
the bin it was originally fed from. This ensures
that the final blend will be the desired percent
Virgin. Once the blender contains the desired
amount of Used powder and Virgin powder, it
blends the powder within the blender to obtain a
uniform batch. Once blending is complete, the
IRS resumes processing other transfer requests
for loading Virgin or Used Powders into their
respective bins or supplying blended powder to
the Sinterstations connected to the IRS.
View or Change the Used/Virgin Powder
Ratio