BACKGROUND OF THE INVENTION
[0001] The invention generally relates to an alignment device for aligning arced silo panels
to form a silo wall during construction of a silo. The invention may also relate to
a lifting device for lifting silo panels during the construction of a silo, and an
arced silo panel for the construction of a silo. The invention may further relate
to a method for constructing a silo. A silo may be understood to encompass storage
tanks, in particular large storage tanks.
[0002] Mass production of increasing amounts of goods of varied nature makes it necessary
to build storage structures of a proportionally growing capacity for storing materials.
Industries such as the petrochemical, biodiesel, oil and the dairy industry, as well
as wastewater treatment plants, water purification plants and, in general, every industry
requiring the storage of large quantities of fuel, liquids, grains and other products,
need large size silos in order to achieve competitive prices in the purchase of raw
materials as well as in large-scale production.
[0003] The construction of large size silos presents a number of technological challenges
which are hard to address. A silo is generally constructed using a multiplicity of
stacked cylindrical rings to achieve the desired height. The traditional construction
system starts from the base of the silo. The walls are built up from below, using
cylindrical rings, starting from the lowest ring welded to the base and ending with
the construction of the roof and the subsequent attachment of all fittings (ladders,
piping, telemetry and control systems, etc.). This approach to the construction of
silos brings about difficulties with regards to, amongst others, required equipment,
safety, alignment, and quality of welding.
[0004] Attempts have been made to overcome the problems associated with the traditional
methods of silo construction. For example, to ensure that the equipment necessary
to join the cylindrical rings is not required to be raised, the silo under construction
may be raised so that a new cylindrical ring may be provided under the part of the
silo which is already constructed. As such, the silo under construction is raised,
rather than all the materials necessary to form a new cylindrical ring. In this manner,
e.g. welding equipment and/or alignment equipment, as well as the parts forming the
new cylindrical rings, may be kept on the ground, which improves safety and efficiency.
[0005] A known method of constructing silos is to provide a multiplicity of separate silo
panels, which are joined to form a cylindrical ring. These separate silo panels are
generally pre-bent and often comprise outwardly projecting flanges around the periphery
of the silo panel. Such separate silo panels are shown in
WO00/49249. Even in such systems, the alignment of the silo panels provides significant challenges.
[0006] It is therefore desirable to provide an alignment device for the construction of
a silo that has benefits and/or overcomes one or more disadvantages of silo construction
devices/methods of the prior art. Exemplary benefits may be achievement of improved
efficiency, lowered safety-risks, lowered production costs, and/or higher quality
of the silo construction.
[0007] In the below relative positions will be mentioned, such as upper and lower. In the
below, those positions refer mostly to the respective positions in the under construction
silo. It will clear however that those positions can be generalized. Upper and lower
generally refers to a first and a second at a distance. The invention is not limited
to the specific in use positions.
BRIEF SUMMARY OF THE INVENTION
[0008] The present invention addresses these problems by providing an alignment device for
aligning panels, in particular arced silo panels, to form a silo wall during construction
of a silo. The alignment device may comprise a base frame supporting an outer side
and an inner side. The base frame with inner and outer side may form a U-shape having
a space for receiving an arced silo panel in between the outer and inner side. Such
an arrangement allows engaging the arced silo from multiple sides. The open side of
the U-shape allows connecting a new arced panel to an existing arced part, e.g. an
arced silo panel that is already part of the silo under construction.
[0009] The alignment device may further comprise at least one clamping unit provided on
the outer side of the base frame, the clamping unit being arranged to clamp two flanges
of a lower arced silo panel and upper arced silo panel together. In other or additional
embodiments, the clamping unit may be on the inner side, or on both inner and outer
side, of the base frame for clamping flanges that are part of an inner periphery of
a lower and upper arced silo panel.
[0010] The alignment device may further comprise at least one pressing unit, comprising
an inner panel aligner provided on the innerside and an outer panel aligner provided
on the outer side. The pressing unit may be arranged to engage the lower arced silo
panel and the upper arced silo panel, wherein the pressing unit is arranged to provide
opposing alignment forces on inner and an outer sides of lower and upper arced silo
panels.
[0011] Preferably, the pressing unit and the clamping unit are arranged to align the lower
arced silo panel and the upper arced silo panel radially and vertically. The pressing
an clamping units can position and align a new arced panel with an existing arced
part, e.g. an arced silo panel that is already part of the silo under construction.
To manipulate the position of the new arced silo panel with respect to the existing
part, the clamping and pressing unit engage the new arced silo panel and the existing
silo part. For constructing a silo, a new arced silo panel is added to the already
constructed part of the silo that comprises other arced silo panels. The new part
is to be held in position and is to be aligned with an arced silo panel that is already
part of the partially constructed silo. To that end the pressing and clamping units
engage on inner and outer sides of the arced silo panels during construction for positioning
and aligning.
[0012] Further, the alignment device may have a drive arranged to move along a existing
part of the silo under construction, that existing part being a stationary part. This
allows to move the alignment device in a circumferential direction along arced panels,
along the wall region of the silo under construction. As a result, the silo under
construction can remain stationary, while the alignment device travels around its
periphery. This is highly advantageous as it mitigates the need for rotating the entire
silo during construction. Driving the alignment device allows moving the alignment
device to a position that allows aligning the new arced silo panel into position with
reduced lever. The alignment device can be driven to positions that allow engaging
closer to misaligned regions. The alignment device can also be driven, after positioning
and aligning and preferably fixing a new arced panel to the silo under construction,
to a further position where it can receive the next new arced silo panel and start
with positioning and aligning that next arced silo panel.
[0013] To mount the pressing and clamping units in a suitable position for alignment of
the arced silo panels, the base frame has an outer and an inner side. The pressing
and clamping units can then engage on inner and outer side of the received arced silo
panel. In addition, the use of such a U-shape ensures that forces exerted on either
side of the arced silo panels are communicated, thus providing opposing alignment
forces. In an embodiment, the base frame, the outer side, and the inner side, are
formed from a single frame defining U-shape, the frame defining the outer and the
inner side. This is advantageous since the forces that need to be transferred between
the outer side and the inner side are large, requiring high structural loads to be
transferred through the U-shape. Preferably, these loads are transferred with low
deformation of the U-shape. In an another embodiment, the base frame, the outer side,
and the inner side are separately joined components, which act together to form the
U-shape.
[0014] The clamping unit can generally exert a force in a vertical direction, resulting
in bringing the new arced silo panel in a desired vertical position with respect to
the arced silo panel of the under-construction-silo. In embodiments, the clamping
unit is arranged to clamp two flanges of two arced silo panels together. In particular,
when a new arced silo panel is provided into the system, underneath an existing cylindrical
ring, the new arced silo panel is aligned with the existing cylindrical ring by clamping
the top flange of the new arced silo panel together with the bottom flange of the
arced silo panel above, which forms a part of the existing cylindrical ring. In this
manner, the height of the new arced silo panel, and thus its height alignment with
respect to the existing cylindrical ring, is set.
[0015] In embodiments, the silo is built from prefabricated pieces, in particular arced
silo panels. In embodiments the arced silo panels are formed and shaped at the work
location. The invention will be described with reference to arced silo panels, the
silo can be formed from other pieces. Preferably the arced silo panels have a horizontal
flange when the arced silo panel is part of the silo. The flange preferably extends
in the radially outward direction, along a periphery of the arced silo panel. A horizontal
flange of an arced silo panel already part of the silo can be engaged by the clamping
unit and allows positioning the alignment device with respect to the already-partially
constructed silo. A new arced silo panel having a similar horizonal flange can be
aligned with the horizontal flange of an arced silo panel already part of the silo.
The flanges will abut, which also allows connecting the flanges. The clamping unit
can clamp on the top side of one flange and on the bottom side of the other flange,
clamping the flanges together, resulting in alignment in the vertical direction.
[0016] The pressing unit can generally exert force on the new arced silo panel in a radial
direction. To that end, the pressing unit can have an inner and an outer panel aligner.
The new arced silo panel can be engaged at multiple spots. The silo-under-construction
can be engaged at multiple spots. The pressing unit can be controlled to bring the
new arced silo panel aligned with the already existing silo part in the circumferential
direction. The pressing unit can provide opposing radial forces against both the newly
provided arced silo panel and the existing cylindrical ring. As a result, the inner
surface of the new arced silo panel and the inner surface of the existing cylindrical
ring align, to radially align the new arced silo panel with the existing structure.
Simultaneously, the outwardly extending peripheral flange of the new arced silo panel
is aligned with the flange of the existing cylindrical ring.
[0017] In a preferred embodiment, the clamping unit comprises two opposing clamping wheels.
These wheels may be provided on two substantially parallel and substantially horizontal
axes, said axes being vertically spaced from one another. The clamping wheels are
preferably arranged to clamp two flanges of two arced silo panels together. The wheels
are mounted on rotatable shafts that e.g. are connected to the frame via one or more
bearings.
[0018] In embodiments the clamping unit comprises two opposing clamping wheels. The wheels
can roll over the flange of the silo, in particular a flange of the silo panel. This
allows the alignment device to move along the wall region of the silo under construction.
As a result, the silo under construction can remain stationary, while the alignment
device travels around its periphery. This is highly advantageous as it mitigates the
need for rotating the entire silo during construction.
[0019] In a preferred embodiment, at least one of the clamping wheels is driven to move
the alignment device along the silo wall. In an alternative or additional embodiment,
an external drive system may be provided to move the alignment device along the stationary
silo wall. In an embodiment, at least one of the horizontal axes of the clamping wheels
is driven by a drive unit. In a preferred embodiment, the drive unit is an electromotor.
Preferably, a single drive unit is arranged to drive multiple axes, by a drive chain,
provided over two or more axes. That way, if one axis is driven, it will translate
rotational force to a second axis.
[0020] In a preferred embodiment, the clamping wheels are made of a hard material, preferably
a metal, more preferably of steel. Since the coefficient of friction between the material
of the arced silo panels and such wheels is generally low, it is preferred to have
more than one wheel being driven to prevent the wheels from spinning on the surface
of the flange or on the surface of the arced silo panel. That way, more control is
provided over the alignment device due to improved traction between the arced silo
panels and the wheels.
[0021] In a preferred embodiment, the clamping unit is arranged to suspend the alignment
device from a flange of an arced silo panel. In such an embodiment, the alignment
device is suspended from the silo under construction. As a result, the alignment device
can freely move around the periphery of the silo without the need of additional guiding
material, such as tracks, cables, carts, or the like. In addition, the friction required
to move the alignment device is reduced, so that a drive unit needs less power to
move the alignment device along the silo wall. The clamping unit provides the necessary
force to clamp the alignment device onto the flange and to suspend the alignment device
from the flange.
[0022] When a new arced silo panel is provided into the system, it is attached to the arced
silo panel which was previously joined to the silo under construction. This is done
by joining straight opposing side sections of the peripheral flange using e.g., bolts.
The connected side sections extend generally in a vertical direction. The new arced
silo panel is also grabbed by the clamping unit at the top flange that will generally
extend in the horizontal direction. The top flange of the new arced silo panel is
then clamped together with the bottom flange of the existing cylindrical ring, above
the new arced silo panel. The new arced silo panel and the alignment device are then
suspended from the bottom flange of the existing cylindrical ring.
[0023] As the alignment device is driven along the periphery of the silo, the silo being
stationary, the seam between the new arced silo panel and the existing cylindrical
ring is welded, thereby joining the new arced silo panel to the existing structure.
In other embodiment a temporary connection is provided first before a permanent connection
such as welding. As a result of this procedure, the weld is only provided as the new
arced silo panel is aligned with the existing structure.
[0024] In an embodiment, the alignment device further comprises one or more wheels provided
on the base frame, the wheel being arranged to support the alignment device on the
ground, and to move the alignment device along the periphery of a silo under construction.
In an embodiment, the alignment device further comprises a rail wheel provided on
the base frame, the rail wheel being arranged to support the alignment device on a
track.
[0025] Alternatively, or in addition to at least partial suspension of the alignment device,
a rail wheel may be provided on the base frame, such that the alignment device can
be moved along a track provided on the floor of the silo to be constructed. In such
an embodiment, a track is provided in the shape of the silo to be constructed, and
the alignment device travels along the track to build up the silo structure. Such
an arrangement may aid in stability of the system and may reduce load on the flanges
of the arced silo panels.
[0026] In an embodiment, the inner panel aligner may comprise at least one inner pressing
unit. The inner pressing unit may comprise at least one inner pressing wheel. The
inner pressing wheel may be provided on a substantially vertical axis and preferably
being arranged to engage with two arced silo panels and to provide an outwardly directed
pressing force on the two arced silo panels.
[0027] In an embodiment, the outer panel aligner may comprise at least one outer pressing
unit. The outer pressing unit may comprise at least one outer pressing wheel. The
outer pressing wheel may be provided on a substantially vertical axis and preferably
being arranged to engage with two arced silo panels and to provide an inwardly directed
pressing force on the two arced silo panels.
[0028] The use of an inner and/or an outer pressing unit having at least one inner and outer
pressing wheel, respectively, allows the alignment device to travel along the arced
silo panels, while reducing friction. As a result, a high pressing force can be exerted,
without a high friction while the alignment device travels along the silo wall. As
such, the alignment device can be moved along the wall of the stationary silo under
construction, while allowing for large alignment forces to be applied by the pressing
unit.
[0029] In a preferred embodiment, the inner panel aligner comprises at least two inner pressing
wheels provided on a substantially vertical axis. In an embodiment, the inner pressing
wheels may be provided on separate substantially vertical axes. By providing at least
two pressing wheels, the inner panel aligner can provide pressing forces on two arced
silo panels without providing a force to the seam between the two arced silo panels.
This is advantageous since the seam is preferably welded, the generated heat of which
may lead to increased malleability.
[0030] In addition, the provision of two vertically spaced inner pressing wheels that are
arranged to engage a lower and a upper arced silo panel respectively, allows for access
to the seam between the new silo arced silo panel and the existing cylindrical ring.
As a result, the welding may occur closer to the point where the arced silo panel
is best aligned.
[0031] Similarly, in an embodiment, the outer panel aligner comprises at least two outer
pressing wheels, which are arranged to provide a pressing force to two arced silo
panels without engaging the flanges in the seam area of the two arced silo panels.
[0032] In an embodiment, the alignment device may further comprise a pre-alignment unit
comprising a further clamping unit and/or a further pressing unit, said pre-alignment
unit being arranged at a lateral distance such that the pre-alignment unit is arranged
to engage with an arced silo panel to pre-align the arced silo panel. The pre-alignment
unit is positioned upstream, so in the driving direction, from the main alignment
units
[0033] The pre-alignment unit is preferably positioned at a lateral distance such that it
is the first point of contact for a new arced silo panel. The pre-alignment unit can
then bring the arced silo panel in a position such that it can be engaged by the rest
of the alignment device. This allows the tolerances of the rest of the alignment unit
to be lowered, since the pre-alignment unit can bring the new arced silo panel in
such a position that it already closely conforms to its eventual position. The engagement
points of the alignment device on a first side are provided by the pre-alignment unit,
while the engagement points on a second side are defined by the last clamping unit
and/or pressing unit of the alignment device. These engagement points define a distance
therebetween. In a preferred embodiment, the pre-alignment unit is provided at a lateral
distance such that the ultimate distance between the engagement points is more than
the length of an arced silo panel, preferably of about the length of two arced silo
panels. In an embodiment, the distance between the engagement points between about
1 and 8 meters, preferably between about 2 and 6 meters.
[0034] In an embodiment, the alignment device may further comprise a welding unit. The welding
unit preferably comprises a welding torch mounted on the inner side of the base frame.
In a preferred embodiment, the welding torch is mounted adjacent to the inner panel
aligner. The welding torch is preferably arranged to provide an elongated weld along
two arced silo panels as the alignment device travels along the arced silo panels.
[0035] In a preferred embodiment, a welding unit is integrated in the alignment device so
that the aligned panels are automatically welded upon placement. As a result, the
weld is integral with the alignment procedure and risks associated with manual welding
are lowered.
[0036] In an embodiment, the alignment device further may comprise at least two laterally
positioned clamping units, preferably at least four laterally positioned clamping
units, more preferably six laterally positioned clamping units. By providing multiple
laterally positioned clamping units, the new arced silo panels are better aligned
and balanced in the alignment device. In addition, a multiplicity of clamping units
can also divide a driving force better, preventing the wheels to slip on the flanges.
[0037] In embodiments, multiple clamping units, each with wheels are provided, each engaging
on the flange of the silo. This allows welding at a position in between two clamping
units. This makes sure that the flanges are correctly clamped and held in aligned
positions during welding.
[0038] In an embodiment, the alignment device may comprise at least two laterally positioned
pressing units, preferably comprising at least three laterally positioned pressing
units, more preferably comprising at least four laterally positioned pressing units.
[0039] In an aspect of the invention, there is provided an arced silo panel for the construction
of a silo. In an embodiment, the arced silo panel comprises an arced wall defining
a section of a cylindrical shape to form a silo panel body being arced in a first
angular direction, and substantially straight in a second direction defining a height,
perpendicular to the first angular direction. As a result, a multiplicity of laterally
positioned panel bodies defines a cylinder. Further, the arced panel body defines
a convex outer surface.
[0040] In an embodiment, the arced silo panel may comprise a circumferential flange provided
around the periphery of the arced panel body, said flange extending outwardly, in
the direction of the convex outer surface. The flange may define arced top and bottom
sections, and straight opposing side sections. The flange may be interrupted at the
ends of the opposing side sections. This allows a wheel to pass over the arced top
and bottom sections, between adjacent arced silo panels. Advantageously, such an arced
silo panel allows the continuous movement of the alignment device having clamping
units with wheels. That is, the clamping wheels can continuously move over the flanges
of arced silo panels forming the silo, without being interrupted by a side flange.
The opening provided in the opposing side sections by interrupting the flange thus
allows for a continuous movement of the alignment device.
[0041] In an embodiment, the arced silo panel may comprise a lifting clamp extending outwardly
from the outer surface. In a preferred embodiment, the lifting clamp is provided at
a distance of about a quarter along the first angular direction of the arced silo
panel, said lifting clamp comprising an engagement element to communicate with a lifting
device. Preferably, the lifting clamp extends substantially parallel to the straight
opposing side sections.
[0042] The provision of a lifting clamp allows a lifting device to engage with the silo
panel to lift the silo once a cylindrical ring has been formed from the arced silo
panels. By lifting the silo using such lifting devices, the silo is raised for the
formation of a new cylindrical ring.
[0043] In an embodiment, the lifting clamp is provided centrally along the arced wall. In
such an embodiment, the central lifting clamp is provided substantially in the middle
of the first angular direction.
[0044] The use of a central lifting clamp a lifting device to raise the silo even if the
subsequent panels are provided in a staggered manner with respect to the previous
cylindrical ring. In particular, the use of a central lifting clamp ensures that the
lifting device can either engage with the combination of two opposed side flanges
of lateral panels, or engage with the central lifting clamp. Either way, a staggered
pattern of silo panels can be used without the need to shift the lifting devices to
lift the silo to the next level.
[0045] In an embodiment, the central lifting clamp extends upwards over between about 5%
and 80% of the height, preferably to between about 5% and 60% of the height, more
preferably to between about 5% and 50% of the height. A lower central lifting clamp
ensures that the panel can be grasped with less height of the lifting device required.
The same holds for a lifting clamp being provided on the silo panel.
[0046] In an aspect of the invention, there is provided a lifting device for lifting arced
silo panels during the construction of a silo. The lifting apparatus may comprise
a base, a vertical frame, connected to the base, and a lifting jack, arranged to travel
along the vertical frame.
[0047] In an embodiment, the lifting jack may comprise an engagement unit, preferably a
hook. Preferably, said engagement unit is moveable in a direction substantially perpendicular
to the vertical frame, so that the engagement unit can move outwardly and inwardly
to engage and disengage with an engagement element of the lifting clamp on an arced
silo panel.
[0048] The use of such a lifting device ensures that the silo may be raised during construction
without the need for a lifting device being the height of the silo. Rather, the lifting
device can lift the silo so that a new cylindrical ring can be provided underneath.
The silo can then be placed on the ground or on blocks by the lifting device. The
lifting device will then engage with the engaging element of the silo panels of the
newly formed cylindrical ring, and raise the silo to provide a space for new arced
silo panels for the formation of a ring. The lifting device can then lift the silo
again, to form a space sufficient for the formation of a subsequent cylindrical ring.
[0049] In a preferred embodiment, the engagement unit is a parallelogram hook.
[0050] In an embodiment, the lifting jack may be arranged to engage with the engagement
element of the lifting clamp of the arced silo panel according to any of the embodiments
discussed hereinbefore.
[0051] In an aspect according to the invention, there is provided a method for constructing
a silo. The method comprises the steps of providing a plurality of arced silo panels,
preferably according to any of the embodiments discussed hereinbefore, providing an
alignment device, preferably according to any of the embodiments described hereinbefore,
laterally joining arced silo panels to construct a first cylindrical ring, providing
a lifting device, preferably according to any of the embodiments described hereinbefore,
raising the silo with the lifting device to provide space for a next cylindrical ring,
aligning and joining arced silo panels with the alignment device to form the next
cylindrical ring, and repeating these steps to form the silo.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] The features and advantages of the invention will be appreciated upon reference to
the following drawings, in which:
FIG. 1 is a three-dimensional view according to an embodiment of the invention, showing
silo under construction;
FIG. 2 is a top view according to an embodiment of to the invention, showing the silo
under construction;
FIG. 3 is a side view of the alignment device according to an embodiment of to the
invention, taken at section J-J of FIG. 2, showing the use of the alignment device
during the construction of the silo;
FIG. 4 is a side view of the silo under construction according to an embodiment of
to the invention, showing the use of the lifting device during the construction of
the silo;
FIG. 5 is a side view of the silo under construction according to an embodiment of
to the invention, showing the formation of a new cylindrical ring during the construction
of the silo;
FIG. 6 is a three-dimensional view of the alignment device according to an embodiment
of to the invention;
FIG. 7 is a detailed cross-sectional side view of the alignment device according to
an embodiment of to the invention;
FIG. 8 is a top view of the alignment device according to an embodiment of to the
invention;
FIG. 9 is a side view of the alignment device according to an embodiment of to the
invention; and
FIG. 10 is a top view of the alignment device according to an embodiment of to the
invention, during the construction of the silo.
DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0053] The following is a description of certain embodiments of the invention, given by
way of example only and with reference to the drawings. Relative positions will be
mentioned, such as upper and lower. Those positions refer mostly to the respective
positions in the under construction silo. It will clear however that those positions
can be generalized. Upper and lower generally refers to a first and a second at a
distance. The invention is not limited to the specific in use positions.
[0054] Referring to FIG. 1, a three-dimensional view of a silo 10 under construction is
shown. As shown, the silo is built from a plurality of arced silo panels 12, which
are arced along a first angular direction. Such silo panels 12 comprise an arced wall
defining a section of a cylindrical shape to form a silo panel body being arced in
a first angular direction. In the illustrated embodiment the arced silo panels are
substantially straight in a second direction. In FIG. 1, the first angular direction
extends substantially horizontal, while the second direction is substantially vertical.
During the construction of the silo 10, a multiplicity of laterally positioned panels
define a cylindrical ring. The panels are formed by arced silo panels. The ring forms
a level of the silo.
[0055] The silo panels 12 comprise a circumferential flange provided around a part of the
periphery of the panel body. Here said flange extends outwardly. In the shown embodiment,
the flange extends around a major part of the curved shape of the arced silo panel
and defines arced top and bottom sections, and a flange extends along the straight
(vertical) opposing side sections. The flange is preferably interrupted at the two
ends of the opposing side sections close to the curved flange. The formed opening
in the flange, of about 2-15cm, preferably 4-10cm, allows a wheel to pass over the
arced top and bottom flange sections, between adjacent panels 12, during the construction
of the silo 10. Preferably the arced silo panel has four openings in the circumferential
flange. Preferably one or both arced flange extend from one to the other opposing
end. The flange preferably extends generally perpendicular to the surface of the arced
panel, extending about 1-12 cm, preferably about 2-10cm.
[0056] A silo 10 generally has a diameter of between about 5-50 meters, and a height of
between about 5-40 meters. While the present invention is most advantageous for these
sizes, it may also be utilized for smaller or larger silos.
[0057] The silo 10 further comprises a roof 11, which preferably defines a convex shape
on top of the silo 10, forming a dome roof, allowing rain water and/or debris to flow
off. The silo 10 further comprises a floor 14. In embodiments, the floor 14 is omitted,
and the silo is provided directly on the ground, or on e.g. a concrete base.
[0058] As shown, during the construction of the silo 10, a multiplicity of arced silo panels
12 are combined to form the cylindrical shape of the silo 10. The silo panels are
curved such that an integral number of silo panels forms a cylindrical ring of the
silo. The silo panels 12 are provided to the lower end of the silo 10, during construction.
Upon completion of an entire ring, the whole silo 10 is raised, to provide space to
form the next ring. As shown, silo panel 13 is not yet part of the silo 10 and is
provided in the opening defined between the floor 14 of the silo 10 and the next completed
ring of silo panels 12.
[0059] To raise the silo 10 during construction, a plurality of lifting devices 15 is provided.
In embodiments, the lifting device 15 is formed by a base from which a vertical pole
extends upward. A (partial) sleeve over the pole can be moved upwards/downwards. The
sleeve has a drive. The sleeve connects to a lifting arm that can engage panels of
the silo under construction. In embodiments, the number of lifting devices corresponds
with the number of silo panels that form a single ring of the silo.
[0060] The lifting devices 15 raise the under construction silo 10. The lift can take place
once an entire ring of silo panels 12 is connected. The lifting devices 15 engage
the arced silo panels 12. In embodiments, the vertical flange of the silo panels is
engaged. The arced silo panels 12 can have an engagement device, such as a central
lifting clamp 18 welded thereto, preferably on an outer circumference thereof.
[0061] By lifting a finished ring of silo panels, space is formed for positioning new panels
to form a next ring of panels 12. Once an entire ring of panels 12 is provided, the
lifting devices 15 may release the panels 12 and attach to a lower row of panels 12.
This is only necessary when the reach of the lifting devices 15 is insufficient for
the required height of the silo 10.
[0062] As shown in FIG. 1, the panels 12 are provided in a staggered manner 17. In the illustrated
embodiment two laterally positioned side sections of the flange of two adjacent panels
on a first ring coincides with the middle of the arced panel 12 on a higher ring.
At that middle position along the arced panel 12 a central lifting clamp 18 is provided.
In the staggered arrangement, the lifting devices 15 can engage with either the two
laterally positioned flange sections of the panels 12 or with the central lifting
clamp 18 of the panel above, or below. As a result, every ring can be engaged by the
lifting devices 15, even though the panels 12 are provided in a staggered manner 17.
[0063] As further shown, an alignment device 16 is provided for aligning arced silo panels
12 to form a silo wall during construction of a silo 10. The alignment device 16 is
arranged to efficiently position the panels 12 in such a way that they do not need
to be manually aligned with earlier panels 12, thereby increasing the efficiency of
the construction of the silo 10.
[0064] Now referring to FIG. 2, a top view of the silo 10 is shown, without roof 11. It
is noted that features described in relation to this embodiment may be combined with
any other embodiment described herein. As shown, the silo 10 comprises a floor 14,
which in this embodiment is built up from staggered flat panels. The alignment device
16 is shown being engaged with the wall of the silo 10, which is built up from panels
12. The silo 10 is supported by a plurality of lifting devices 16. A cross-section
taken on line J-J of the alignment device 16 is shown in FIG. 3, discussed below.
[0065] The alignment device 16 is arranged to travel along the periphery of the stationary
silo 10 during construction, aligning panels 12 as it travels around the silo 10.
In embodiments, the alignment device 16 suspends on a ring of the silo.
[0066] Now referring to FIG. 3, a side view of the alignment device according to an embodiment
of to the invention is shown, taken at section J-J of FIG. 2, showing the use of the
alignment device 16 during the construction of the silo. It is noted that features
described in relation to this embodiment may be combined with any other embodiment
described herein.
[0067] FIG.3 shows a side view of the silo panel 13. FIG.3 shows the silo panel 13 being
aligned during construction with the existing structure of the silo. The alignment
device 16 engages and is suspended by the existing panel 12 of the silo. The panel
12 of the existing structure is shown in cross-section, since the panels of the silo
are provided in a staggered manner, with the middle of one panel coinciding with an
edge region of a panel above, or below. The alignment device 16 further engages the
panel 13 and clamps it together with the panel 12, which is located above the new
panel 13.
[0068] As shown, the panels 12, 13 have a flange on their periphery. FIG.3 shows the cross-section
of the arced panel at the position where two arced panels 13 sideward connect. As
shown, panel 13 comprises a straight (vertical) side flange 22, and an arced bottom
flange 24 and an arced top flange 25. Near the top and bottom of flange 22 openings
26 are formed. In embodiments, the straight side flange 22 is interrupted at its upper
and lower regions, defining a gap through which the wheels of the alignment device
16 can travel while aligning the panels for the construction of the silo.
[0069] The top flange 25 is clamped together with the bottom flange of the top panel 12
by the alignment device 16. By clamping the flanges of panels 12 and 13 together,
panels 13 is brought into position with respect to the already constructed silo. Panel
13 can then be connected, e.g. by welding, to the already formed silo.
[0070] In an embodiment, the bottom flange 24 is held by a bottom clamping unit. This may
be advantageous to stop the bottom panel 13 from freely swinging while it is clamped
together with the top panel 12.
[0071] Alignment device 16 comprises a base frame 27 supporting an outer side 28 and an
inner side 29, forming a U-shape having a space for receiving an arced panel 13 in
between the outer 28 and inner side 29. On an inner side 29 a platform for supporting
a worker is formed. A ladder makes the platform accessible.
[0072] Now referring to FIG. 4, a side view of the silo under construction according to
an embodiment of to the invention is shown, detailing the use of the lifting device
during the construction of the silo. It is noted that features described in relation
to this embodiment may be combined with any other embodiment described herein. The
figures shows a silo 50 under construction, showing a roof 51 being built up using
ring elements 52 and 52' to form a first ring supporting the roof 51. These ring elements
52, 52' at least have a radially outwardly directed flange on the lower side. This
way, the alignment device can clamp the lower flange of the ring elements together
with the upper arced flange of the silo panel underneath. Silo panels 53 and 54 are
connected to the ring elements 52 and 52', as well as to each other. The silo panels
53, 54 have outwardly directed radial flanges, which are used to align the panels
to each other and to the existing structure. The silo 50 under construction is carried
by lifting devices 60, comprising a base 61, a vertical frame 62 acting as a guide
and connected to the base 61, and a lifting jack 63, 64, arranged to travel along
the vertical frame 62. The lifting jack 63, 64 preferably comprises a sleeve like
element 63 comprising and/or being integrally formed with an engaging unit 64. Preferably,
the engaging unit is a parallelogram hook.
[0073] Vertical frame 62 is positioned at a distance from the panels to allow the alignment
device 16 to move on an inner side thereof without colliding.
[0074] As shown in FIG.4, the hook 64 is not engaged with the engagement element 56 of the
lifting clamp provided on the silo wall. If the hook is not engaged, the silo 50 rests
on temporary supports 70, which may be folded away when not in use.
[0075] In embodiments, the arced silo panel is provided comprising an arced wall defining
a section of a cylindrical shape to form a silo panel body being arced in a first
angular direction defining a width, and substantially straight in a second direction
defining a height, perpendicular to the first angular direction so that a multiplicity
of laterally positioned panel bodies defines a cylinder and such that the arced panel
body defines a convex outer surface. The arced silo panel can have a circumferential
flange provided around the periphery of the arced panel body, said flange extending
outwardly, in the direction of the convex outer surface. This can be a partial flange
or a flange extending along the full length. In embodiments the silo panel has a flange
along the arced top and bottom sections. In embodiments the silo panel has a flange
extending along vertical side sections, preferably both opposite side sections. In
embodiments the side flange is interrupted at the ends of the opposing side sections,
to allow a wheel to pass over the arced top and bottom sections, between adjacent
arced silo panels.
[0076] In embodiments the arced silo panel 53, 54 has a engagement element 56 for a lifting
device. The engagement element is preferably mounted to an outer side of the arced
silo panel. In embodiments that engagement element is adapted to be engaged by a hook
like lifting device.
[0077] In embodiments the arced silo panels are rotationally symmetric, except for the engagement
element of the lifting clamp. Preferably the engagement element is positioned at about
¼ and/or ¾ of periphery of the arced silo panel. In such an arrangement, the positions
of the engagement elements are, even though the silo panels are staggered, at the
same peripheral position, albeit vertically at a distance. This allows the lifting
device to pick up the next level without having to make a peripheral movement, while
providing only two kinds of silo panels. Moreover, the silo panel have only a single
engagement element or lifting clamp. The silo panels can have multiple engagement
elements.
[0078] In an embodiment different from FIG.4, the engagement element extends and is positioned
at similar distances from the top and bottom flange at ¼ of the periphery. The engagement
element can be arranged to be engaged for lifting on both vertical sides. This embodiment
then allows positioning the silo panel in a staggered manner, with the side panels
of one ring positioned upside down with respect to the side panels of the next ring.
In this embodiment only a single kind of arced panels is needed.
[0079] Now referring to FIG. 5, a side view of the silo under construction according to
an embodiment of to the invention is shown, detailing the formation of a new cylindrical
ring during the construction of the silo. As shown in FIG. 5, the silo 200 is raised
using the lifting devices 205, which are engaged with the arced silo panels to lift
the silo under construction to such an extent that new arced silo panels 204, 203
may be provided underneath for continued construction of the silo.
[0080] While the silo is raised by the lifting devices 205, the alignment device 201 is
provided to the lower flange of the arced silo panels of the raised silo 200 such
that the alignment device 201 is suspended from the arced silo panels. The suspended
alignment device can move in the peripheral direction around the formed silo, without
colliding with the lifting device. The lifting devices 205 are positioned at a distance
further from the centre of the silo 200 then the outer most part of the suspended
alignment device, although e.g. support legs of the lifting device can extend more
inwardly. The lifting device is generally U-shaped, with the open end of the U receiving
the alignment device.
[0081] A new arced silo panel 204 is provided to the space between the inner and outer side
of the alignment device 201, while the alignment device is suspended from the lower
arced flange of the top arced silo panel. Upon the provision of the new arced silo
panel 204, the top flange of the new arced silo panel 204 is clamped together with
the lower arced flange of the top arced silo panel. The alignment device 201 travels
along the periphery of the silo to continuously clamp and align the two silo panels
and to weld the new arced silo panel 204 to the existing silo structure.
[0082] A still further arced silo panel 203 is then provided to the system by raising it
using panel lifting stands 206, provided underneath the new arced silo panel 203 to
raise it so that it may be connected to the arced silo panel 204. The straight side
flanges of the panels 204 and 203 are connected using e.g. bolts, after which the
alignment device 201 travels along the arced flanges of panels 204 and 203 to align
the new panels with the existing structure and to weld the panels to the existing
structure, thereby creating a further cylindrical ring 202 for the formation of the
silo.
[0083] Many different methods and method steps can be used to form the silo using the alignment
device of the invention. The invention is in no way limited to the shown method steps.
[0084] Now referring to FIG. 6, a three-dimensional view of the alignment device 800 according
to an embodiment of to the invention is shown. The alignment device 800 comprises
a base frame 88 having an inner side 81 and an outer side 80. As the alignment device
800 is configured to receive a silo panel, the inner and outer side 81,80 are positioned
on the two sides of that silo panel. The inner and outer side 81, 80 with respect
to a silo panel 100 are better shown in Fig.9.
[0085] In this embodiment, the inner side provides a platform 89 where a worker can be positioned
to monitor the process and to provide alterations to e.g., the welding process. Accordingly,
the alignment device is arranged to weld silo panels on an inner side thereof. The
alignment device 800 further comprises a welding arrangement, provided on the inner
side 81.
[0086] The alignment device 800 may further comprise a plurality of clamping units 82, 85,
arranged to clamp the flanges of two panels together. The clamping units 82, 85 are
provided on the outer side 80, the clamping units 82, 85 being arranged to clamp two
flanges of a lower arced silo panel and newly positioned upper arced silo panel together.
The clamping units 82, 85 each comprise a plurality of opposing clamping wheels, here
four, provided on substantially parallel and substantially horizontal axes, said axes
being vertically spaced from one another. The clamping wheels are arranged to clamp
two flanges of two arced silo panels together.
[0087] The wheels of the clamping unit are also arranged to suspend from the flange. In
embodiment the centre of gravity of the alignment device is close to or in the plane
of the flange of the silo panel.
[0088] The wheels of the clamping unit allow movement of the alignment device over a flange
of an arced silo panel. The clamping wheels are driven by one or more drives 83, which
are arranged to provide a driving force to move the alignment device 800 along the
periphery of the silo under construction.
[0089] The alignment device 800 further comprises a plurality of outer panel aligners, which
form part of the pressing unit. The inner panel aligners are not shown for clarity.
The outer panel aligners comprise at least one outer pressing unit comprising at least
one outer pressing wheel 86 provided on a substantially vertical axis, the outer pressing
wheels 86 being arranged to engage with two arced silo panels and to provide an inwardly
directed pressing force on the two arced silo panels. In the shown embodiment, the
outer pressing wheel 86 provides a force directed inwardly.
[0090] In the specific embodiment of Fig.6, one wheel 86 can engage the lower flange of
the two clamped flanges and press that flange inwardly until wheel 86 engages on the
two flanges, including the upper flange of the already part-of-the-constructed silo
panel. To the end the wheel 86 is positioned at a height / horizontal plane that correspond
to the height of the space between the upper and lower clamping wheel of clamping
units 82,85. In an alternative or additional embodiment, outer pressing wheels may
be provided in a vertically spaced manner such that they engage with the top and bottom
arced silo panels separately.
[0091] The alignment device 800 further comprises a pre-alignment unit 84 comprising a further
clamping unit and/or a further pressing unit 87. The pre-alignment unit 84 is arranged
at a lateral distance such that the pre-alignment unit is arranged to engage with
an arced silo panel to pre-align the arced silo panel. This allows the pre-alignment
unit 84 to limit misalignment of arced silo panels being moved between the inner and
outer side of the alignment device 800.
[0092] Now referring to FIG. 7, a detailed cross-sectional side view of the alignment device
according to an embodiment of to the invention is shown, where the left side shows
the inner side of the alignment device, and the right side shows the outer side of
the alignment device.
[0093] The inner panel aligner 120 provides a pressing force in direction 127, such that
the top panel 100 and the bottom panel 104 are radially aligned. The pressing force
is provided in direction 127 by the pressing unit 123, which is connected to the frame
121.
[0094] The top panel 100 has a vertical flange 101 and a horizontal flange 102. The bottom
panel 104 has a horizontal flange 105. The outer panel aligner 132 presses in a direction
opposite to direction 127 such that a reaction force may be applied between the inner
and outer panel aligners to radially align the panels 100, 104. This alignment will
be shown in more in detail with reference to FIGs 8-10.
[0095] The clamping unit comprises two wheels 110, 111, which are provided on substantially
horizontal axes 112, 113, respectively. The bottom horizontal shaft 112 can pivot
in direction 115, along guide 116 to move wheel 110 away from wheel 111, allowing
the entry of to flanges 102, 105 between the wheels 110, 111, even if the flanges
102, 105 are slightly spaced apart. For clamping, the wheels 110 and 111 are moved
towards each other. Suitable hydraulic means can be used.
[0096] Now referring to FIG. 8, a top view of the alignment device according to an embodiment
of to the invention is shown. Here, the inner panel aligner 113 is shown, providing
an opposite force to the outer panel aligner, having outer pressing wheels 132 to
radially align the panels. The pre-alignment device 130 is arranged to provide the
panels entering from side 131 into the system such that the panels are accepted in
the further clamping units without large misalignment.
[0097] Referring now to FIG. 9, a side view of the alignment device according to an embodiment
of to the invention is shown. The inner alignment unit 120 is shown to have two inner
pressing wheels 122 which provide an alignment force opposite to the outer pressing
wheel provided on a vertical axis on the outer side 80 of the alignment device. FIG.
9 further shows that the panels 100, 104 are clamped together using clamping wheels
110, 111, which are provided on horizontal axes. Once clamped, the welding unit 140
joins the two panels together.
[0098] Now referring to FIG. 10, a top view of the alignment device 316 according to an
embodiment of to the invention is shown, during the construction of the silo. The
pre-alignment unit 318 positions the new panel 312 such that it is received by the
pressing unit, comprising the inner panel aligner 320 and the outer panel aligner,
having outer pressing wheels 321, 323. As illustrated in Fig. 10, wheels 321,323 engage
on an outer side of the clamped flanges, while clamping wheel 322 engage on a top
side of the clamped flange. Further, the alignment device 316 comprises a clamping
unit 325, arranged to vertically align the panels such that the welding unit 340 can
join the panels together. A still further arced silo panel 313 is attached to the
new arced silo panel 312, before it is brough into pre-alignment by the pre-alignment
unit 318 and provided to the pressing unit and the clamping unit.
[0099] Thus, the invention has been described by reference to certain embodiments discussed
above. It will be recognized that these embodiments are susceptible to various modifications
and alternative forms well known to those of skill in the art. In particular, while
different reference signs have been used in different figures to denote similar or
the same components, these may be combined to form further embodiments.
[0100] Further modifications in addition to those described above may be made to the structures
and techniques described herein without departing from the spirit and scope of the
invention. Accordingly, although specific embodiments have been described, these are
examples only and are not limiting upon the scope of the invention.
1. An alignment device for aligning arced silo panels to form a silo wall during construction
of a silo, the alignment device comprising:
- a base frame supporting an outer side and an inner side, forming a U-shape having
a space for receiving an arced silo panel in between the outer and inner side;
- a drive arranged to move along a stationary silo wall during construction of the
silo ;
- at least one clamping unit provided on the outer side; and
- at least one pressing unit, comprising an inner panel aligner provided on the inner
side and an outer panel aligner provided on the outer side, the pressing unit being
arranged to engage the lower arced silo panel and the upper arced silo panel;
wherein the clamping unit being arranged to clamp two flanges of a lower arced silo
panel and upper arced silo panel together,
wherein the pressing unit is arranged to provide opposing alignment forces on inner
and an outer sides of lower and upper arced silo panels, and
wherein the pressing unit and the clamping unit are arranged to align the lower arced
silo panel and the upper arced silo panel radially and vertically.
2. The alignment device of claim 1, wherein the clamping unit comprises two opposing
clamping wheels provided on two substantially parallel and substantially horizontal
axes, said axes being vertically spaced from one another, the clamping wheels being
arranged to clamp two flanges of two arced silo panels together and wherein the clamping
unit is preferably arranged to suspend the alignment device from a flange of an arced
silo panel
wherein preferably the drive is arranged to drive the clamping wheels to move the
alignment along the periphery of the stationary silo.
3. The alignment device of claims 1 or 2, wherein the alignment device further comprises
a welding unit, the welding unit comprising a welding torch mounted on the inner side,
preferably being mounted adjacent to the inner panel aligner, the welding torch being
arranged to provide an elongated weld along two arced silo panels as the alignment
device travels along the arced silo panels.
4. The alignment device of any preceding claim, wherein the inner panel aligner comprises
at least one inner pressing unit comprising at least one inner pressing wheel provided
on a substantially vertical axis, the inner pressing wheel being arranged to engage
with two arced silo panels and to provide an outwardly directed pressing force on
the two arced silo panels.
5. The alignment device of any preceding claim, wherein the outer panel aligner comprises
at least one outer pressing unit comprising at least one outer pressing wheel provided
on a substantially vertical axis, the outer pressing wheel being arranged to engage
with two arced silo panels and to provide an inwardly directed pressing force on the
two arced silo panels.
6. The alignment device of any preceding claim, further comprising a pre-alignment unit
comprising a further clamping unit and/or a further pressing unit, said pre-alignment
unit being arranged at a lateral distance such that the pre-alignment unit is arranged
to engage with an arced silo panel to pre-align the arced silo panel.
7. The alignment device of any preceding claim, comprising at least two laterally positioned
clamping units, preferably at least four laterally positioned clamping units, more
preferably at least eight laterally positioned clamping units, and/or comprising at
least two laterally positioned pressing units, preferably comprising at least three
laterally positioned pressing units, more preferably comprising at least four laterally
positioned pressing units.
8. The alignment device of any preceding claim, wherein the alignment device further
comprises one or more wheels provided on the base frame, the wheel being arranged
to support the alignment device on ground, and to move the alignment device along
the periphery of a silo under construction and/or wherein the alignment device further
comprises a rail wheel provided on the base frame, the rail wheel being arranged to
support the alignment device on a track.
9. An arced silo panel for the construction of a silo, the arced silo panel comprising:
- an arced wall defining a section of a cylindrical shape to form a silo panel body
being arced in a first angular direction, and substantially straight in a second direction
defining a height, perpendicular to the first angular direction so that a multiplicity
of laterally positioned panel bodies defines a cylinder and such that the arced panel
body defines a convex outer surface;
- a circumferential flange provided around the periphery of the arced panel body,
said flange extending outwardly, in the direction of the convex outer surface;
wherein said flange defines arced top and bottom sections, and straight opposing side
sections, and
wherein said flange is interrupted at the ends of the opposing side sections, to allow
a wheel to pass over the arced top and bottom sections, between adjacent arced silo
panels.
10. The arced silo panel according to claim 9, further comprising a lifting clamp extending
outwardly from the outer surface, preferably provided at a distance of about a quarter
along the first angular direction of the arced silo panel, said lifting clamp comprising
an engagement element to communicate with a lifting device.
11. The arced silo panel according to any of claims 10, wherein the lifting clamp is a
central lifting clamp, provided substantially parallel to the straight opposing side
sections, and provided substantially in the middle of the first angular direction.
12. The arced silo panel according to claim 11, wherein the central lifting clamp extends
upwards over between about 5% and 80% of the height, preferably to between about 5%
and 60% of the height, more preferably to between about 5% and 50% of the height.
13. A lifting device for lifting arced silo panels during the construction of a silo,
the lifting apparatus comprising:
- a base;
- a vertical frame, connected to the base; and
- a lifting jack, arranged to travel along the vertical frame,
wherein the lifting jack comprises an engagement unit, preferably a hook, said engagement
unit being moveable in a direction substantially perpendicular to the vertical frame,
so that the engagement unit can move outwardly and inwardly to engage and disengage
with an engagement element on an arced silo panel.
14. The lifting device according to claim 13, wherein the lifting jack is arranged to
engage with the engagement element of the arced silo panel according to claim 10.
15. Method for constructing a silo, the method comprising the steps of:
- providing a plurality of arced silo panels according to any of claims 9 to 12;
- providing an alignment device according to any of claims 1 to 7;
- laterally joining arced silo panels to construct a first cylindrical ring;
- providing a lifting device according to any of claims 13 to 14;
- raising the cylindrical ring with the lifting device to provide space for a next
cylindrical ring;
- aligning and joining arced silo panels with the alignment device to form the next
cylindrical ring;
- repeating the steps of raising and aligning to form the silo.