3D Systems sPro, Руководство пользователя

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SLS p r o c e s s 1 4 3 I R S & I P C
u s e r ’ s g u i d e h o w t h e I R S & I P C w o r k
Transporter Systems
The left and right transporter systems are similar.
Powder flows from a bin by gravity into an
L-Valve, which controls the flow into a collector
funnel. From the funnel, the powder flows by
gravity into a chamber that can be closed and
pressurized to force powder to the powder
manifold and on to the intended destination.
L-VALVE AND COLLECTOR FUNNEL
The bottom of the L valve contains a permeable
fabric that allows air to flow through it. Air,
flowing through a #13 orifice and the permeable
fabric, provides the motive force to convey the
powder. Note that the number of an orifice is an
indication of the orifice hole size, i.e., a #13 orifice
has a 0.013-inch diameter hole. A larger air flow
will result in a higher powder flow rate. If there
are air leaks around the membrane or at the air
connection, the powder flow rate might be too
low.
The L-Valve empties its powder through the
collector funnel lid and into the collector funnel.
It is important that the L-Valve not touch the
Collector Funnel lid. If it touches here, the
resulting friction will influence the load cell
readings that determine powder weight in the
bins. The dust collection fan will ensure that air
always flows into the gap around the outside to
capture dust.
TRANSPORTER
A conical stopper valve, operated by an air
cylinder, is opened while the transporter is filling
and closes to pressurize the transporter and
convey the powder. The transporter hopper has a
high-level proximity switch, which signals when
the transporter is full. An air line with a # 19
orifice provides air to clean adhered powder off
the proximity switch after each transfer.
The bottom of the transporter or fluidizer is a
permeable membrane similar to that in the L-
Valves. Flow to the fluidizer membrane is
controlled by a #63 orifice. This flow fluidizes the
powder and forces the powder out a side port.
From there, a second air stream dilutes the
powder to limit the ratio of powder to air in the
powder conveying lines. If there is too much
powder, the lines will plug.
POWDER MANIFOLD
The powder manifold is a series of “T” fittings
with the flow out each branch controlled by a
pinch valve. A pinch valve is essentially a rubber
sleeve contained within a cavity that can be
pressurized to “pinch” the rubber sleeve closed.
The pinch valves may only be closed when the
powder flow line is empty or nearly empty. If
closed when full of powder, the powder will be
compressed into a firm agglomerate and will not
clear when the pinch valve is opened.