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METALWORKING EQUIPMENT AND TOOLS
is poured into a receiving
hopper 15 connected to the
sand cooling and cleaning line.
The FTIMS NASU uses high-
performance continuous sand
coolers in a pseudo-boiling
layer, which are built into
automated sand conveying
lines from the knockout position
to the molding position. Since
dry sand (unlike traditional
molding sand mixtures) does
not lose flowability at low
temperatures, such lines are
usually placed outside the
foundry, near its outer wall.
The lower half of the
half-mold from segments
11 is molded similarly to the
upper half-mold, with the only
difference in this embodiment
of the design: on the model
plate with model 16, a partition
17 is installed equal to the
height of the half-mold and
having an angle α at the apex.
Fig. 3. Device for continuous strip from
the melt. device has been developed (Fig. 3a), consisting of a bath 1
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In order to ensure that the side walls of adjacent segments 11
are joined without a gap during assembly, the model plate is
rotated by the specified angle α during molding compared to its
location at the time the model was pulled from the mold.
As shown in cross section (Fig. 2b), the mold has
longitudinal sidewalls with vacuum valves 18 and perforated
walls 19 for sand vaccuuming when valves 18 are connected to
pipelines 20 of the vacuum tracking system for VFM lines. The
mold is moved on rollers 21.
Since there are no transverse partitions on the conveyor,
using the appropriate models in this installation, cavity formation
is possible to obtain long castings in semi-continuous mode.
It should be noted that upon reaching the counterattack
of the form of strips, profits, when the form is filled with metal,
the film burns around them. The depressurized surface of the
sand mold leads to air suction through it and a significant
decrease in the degree of rarefaction in the upper part of the
mold, which requires an increase in the intensive operation
of the pumps to avoid premature softening of the mold. This
question is especially relevant for the installation shown in Fig.
1, during the operation of which extensive open metal surfaces
are possible. For individual molds in areas of manual molding,
in such cases, immediately after pouring, the end face of
the spike or profit is covered with sand, which prevents the
destruction of the nearby film. In the invention [10], sealing
and «warming» of the exposed metal surfaces and parts of
the mold surface around them are performed by covering with
synthetic film bags filled with molding sand. During continuous
casting on a moving conveyor, open metal surfaces and nearby
mold surfaces are covered with a continuously manufactured
sand bag, which is lined with a sand layer on the surface of
the flooded mold, it can be considered an analogue of the non-
flammable sand-film non-vacuum form. This coating is much
more effective for sealing the mold than a simple dusting with
sand. The lower film of the bag in contact with metal burns out,
and the upper film of the lying bag serves as a reliable sealant.
An option is also provided for laying these sandbags on a mold
before pouring metal [10].
For continuous production of a strip from a melt, a roll
METALWORKING EQUIPMENT AND TOOLS
with a melt and a roll 2 with a rotation drive [11]. The roll 2 is of "flowing metal - solid
partially immersed in the melt, has a cavity 3 and a perforated sand" and vice versa, with
shell 4, lined with sand 5 by the VFM method, onto which the the possibility of performing
strip 6 is frozen. In this embodiment of the roll installation, the molding in a continuous mode.
heated top layer of sand is removed by suction through pipe Conveyor molds based on a
7, cutting off the sand with plow 8 (vibrating blower). In the closed belt or plate conveyor,
direction of rotation of the roll 2, sand from the tube feeder lined with dry sand using the
9 is poured onto it from the tubular feeder 9, and a synthetic VPM method, as well as roller
film 10 from the roll 11 is laid on top with the help of the roll devices provide a combination
12, while leveling and compacting the sand layer by known of transport and technological
methods. The roll cavity 3 is evacuated through valve 13 (Fig. operations of the casting
3b), maintaining the pressure in the sand 50 ± 20 kPa below process, thereby increasing
atmospheric. production productivity while
Upon contact with the melt, the synthetic film 10, which reducing its labor intensity.
seals the sand, evaporates, the evaporation products are Such conveyor molding
instantly absorbed into the evacuated cavity of the roll, after technologies using sand
which the sand surface of the roll continues to seal the metal molding make it possible to
in contact with it, the film or strip 6 of which is pressed out of obtain workpieces such as
the sand (due to evacuation), bathtubs in a continuous mode. thin-walled slabs of figured
By varying, within the available limits, the amount of vacuum, profile or strips. They facilitate
melt temperature, temperature and thermal conductivity of the automation of the casting
sand, the duration of contact of the melt with the roll, you can process, including the use of
adjust the thickness of the freezing strip. concomitant progressive methods
Continuing the theme of casting on moving molds, created for automatic operation,
the FTIMS NASU foundry workers are developing methods for example, magneto-dynamic
for producing blanks such as pipes and thin slab blanks in pumps (MDP) for filling molds with
vacuum sand molds that approach the cross section of finished high rates of metering accuracy
products, as well as previously low-tech cellular castings and and metal quality.
cellular materials, which will be discussed in our next articles.
The described conveyor devices represent examples of the
implementation of innovative casting capabilities in vacuum
sand molds. In the first two examples, by controlling the fluidity
and strength of sand, mainly by removing it by approaching the
vacuum filters of the conveyor, they operate on the principle
V.S. Doroshenko
dorosh@inbox.ru
References:
1. Minaev A.A., Notkin E.B., Sazonov V.A. Vacuum forming. M.: Mechanical Engineering, 1984. 216 p.
2. Doroshenko V.S., Sheiko N.I. Nev V-Process Technology produces Bar, Strip and Shaped Casting on a
Continuous Basis.//Foundry International. 1993. March. R. 224-225, 232.
3. Installation for continuous casting: Copyright of 1771131 USSR: MKI V22C 9/02 / Doroshenko B.C.,
Sheiko N.I. from 12.07.90.
4. Installation for casting: Pat. 2070469 Russia, MKI V22C 9/02 / Doroshenko B.C., Sheiko N.I. Pubd.
12/20/1996.
5. Installation for casting: Pat. 2070470 Russia, MKI V22C 9/02. Doroshenko B.C., Sheiko N.I. Pubd.
12/20/1996.
6. Installation for continuous casting: Pat. 2015794 Russia: MKI V22C 9/02. Doroshenko B.C., Sheiko N.I.
Pubd. 1994.07.07.15.
7. Installation for continuous casting: Pat. 2040357 Russia: MKI V22C 9/02. Doroshenko B.C., Sheiko N.I.
Pubd. 1995.07.25
8. The method of applying a synthetic film to a model during vacuum-film molding: Pat. 2020028 Russia,
MKI V22C 9/02. Doroshenko B.C., Sheiko N.I. Pubd. 09/30/1994.
9. Machine for casting blanks: Pat. 2052310 Russia: MKI V22C 9/03. Doroshenko B.C., Sheiko N.I. Pubd.
01/20/1996.
10. A method of producing castings in vacuum-film forms: Pat. 2014939 Russia: MKI B22C 9/02.
Doroshenko B.C., Sheiko N.I. Pubd. 1994.06.30.
11. A device for producing a strip of melt: Pat. 1836841 Russia: MKI B22D 11/06. Doroshenko V.S.,
Sheyko N.I. Pubd.
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