U.S. patent application number 13/602462 was filed with the patent office on 2013-08-29 for protective cover for a ventilation opening.
This patent application is currently assigned to AREVA NP GMBH. The applicant listed for this patent is CARSTEN CHRISTGAU, CLAUDE GRATIEUX, WLADIMIR TRUBNIKOW. Invention is credited to CARSTEN CHRISTGAU, CLAUDE GRATIEUX, WLADIMIR TRUBNIKOW.
Application Number | 20130225066 13/602462 |
Document ID | / |
Family ID | 47710605 |
Filed Date | 2013-08-29 |
United States Patent
Application |
20130225066 |
Kind Code |
A1 |
TRUBNIKOW; WLADIMIR ; et
al. |
August 29, 2013 |
PROTECTIVE COVER FOR A VENTILATION OPENING
Abstract
A protective cover is provided for a ventilation opening in a
plant space of a nuclear-engineering plant. The cover is
configured, with a construction that is simple, and with simple
manufacture and mounting, for a sufficient air-flow cross section
and also for protection against ingress of destructive projectiles
into the building interior. The protective cover has profile
elements, which are arranged in a mounting plane in a rectangular
frame, are aligned in a longitudinal direction such that they are
parallel to one another, and are shaped in the same way and
orientated in the same way. The relevant profile element has an
L-shaped or V-shaped cross section with two limbs that meet in a
peak, with the peaks pointing in the transverse direction. A
spacing between profile elements that immediately follow each other
is chosen such that there is no rectilinear passage between
them.
Inventors: |
TRUBNIKOW; WLADIMIR;
(OFFENBACH, DE) ; CHRISTGAU; CARSTEN; (CHARLOTTE,
NC) ; GRATIEUX; CLAUDE; (FRANKFURT AM MAIN,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TRUBNIKOW; WLADIMIR
CHRISTGAU; CARSTEN
GRATIEUX; CLAUDE |
OFFENBACH
CHARLOTTE
FRANKFURT AM MAIN |
NC |
DE
US
DE |
|
|
Assignee: |
AREVA NP GMBH
ERLANGEN
DE
|
Family ID: |
47710605 |
Appl. No.: |
13/602462 |
Filed: |
September 4, 2012 |
Current U.S.
Class: |
454/367 |
Current CPC
Class: |
F24F 13/20 20130101;
E04C 2/425 20130101 |
Class at
Publication: |
454/367 |
International
Class: |
F24F 13/20 20060101
F24F013/20 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 1, 2011 |
DE |
10 2011 111 666.8 |
Claims
1. A protective cover for a ventilation opening in a plant space of
a nuclear-engineering plant, the protective cover comprising: a
rectangular frame having a longitudinal direction and a transverse
direction; and a plurality of elongate profile elements disposed in
a mounting plane in said rectangular frame, said profile elements
aligned in said longitudinal direction such that said profile
elements are parallel to one another, and are shaped in a same way
and orientated in a same way, wherein each of said profile elements
having an L-shaped cross section or a V-shaped cross section with
at least two limbs that meet in a peak, with said peak pointing in
said transverse direction, and wherein a first spacing between said
profile elements that immediately follow each other is chosen such
that there is no rectilinear passage between said profile
elements.
2. The protective cover according to claim 1, wherein said two
limbs of said profile elements meet in said peak at an angle that
ranges from 80.degree. to 110.degree..
3. The protective cover according to claim 1, wherein, when viewed
in said transverse direction, a second spacing which characterizes
an overlap between a leading edge of said profile element and a
trailing edge of said profile element that is located immediately
in front of it is approximately 0.5% to 5% of a total width of said
profile element in said transverse direction.
4. The protective cover according to claim 1, wherein said two
limbs of said profile elements have same dimensions.
5. The protective cover according to claim 1, wherein said profile
elements have a cross section being constant over an entire
longitudinal extent.
6. The protective cover according to 1, wherein each of said
profile elements have two end faces, at which each of said profile
elements is welded to said frame.
7. The protective cover according to claim 1, wherein said profile
elements are configured in a unipartite manner and produced by
bending an originally planar steel sheet.
8. The protective cover according to claim 1, wherein said
rectangular frame is composed of said profile elements with
U-shaped cross sections or double-U-shaped cross sections.
9. The protective cover according to claim 1, wherein said two
limbs of each of said profile elements meet in said peak at an
angle of 90.degree..
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority, under 35 U.S.C.
.sctn.119, of German application DE 10 2011 111 666.8, filed Sep.
1, 2011; the prior application is herewith incorporated by
reference in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The invention relates to a protective cover (in short:
cover) for a ventilation opening in a plant space or plant building
of a nuclear-engineering plant.
[0003] The plant spaces of a nuclear-engineering plant located
outside the reactor containment include among others for example
what is referred to as diesel generator building, which houses
safety-relevant cooling systems and/or associated diesel
generators. The walls of such plant spaces are provided with
supply-air/exhaust-air openings (in short: ventilation openings),
which are typically configured as solid prismatic
reinforced-concrete ducts. The geometry and through-guidance of
such ducts requires as a rule large planning outlay and high costs.
Not only must the ventilation openings ensure a sufficient air-flow
cross section for the unimpeded operation of the cooling unit.
There should also be provided sufficient ingress protection with
respect to what is referred to as tornado missiles and similar
projectiles and high-energy fragments that are set free during, for
example, a hurricane (tornado) in the vicinity of the relevant
plant building. For this purpose, the relevant ventilation opening
is typically provided with a cover in the manner of a steel grid.
However, it has been found that the hitherto known covers meet the
requirements that are expected of them only in part, such that
there is a need for improvement in this regard.
SUMMARY OF THE INVENTION
[0004] The present invention is therefore based on the object of
further developing a protective cover of the type mentioned in the
introduction such that, with a construction that is kept simple,
and with simple manufacture and mounting, the abovementioned
requirements--sufficient air-flow area and simultaneously
protection against ingress of destructive projectiles into the
building interior--are met to a high degree.
[0005] This object is achieved according to the invention by the
features of the claims.
[0006] Accordingly, a protective cover for a ventilation opening in
a plant space of a nuclear-engineering plant is provided. The cover
has a plurality of elongate profile elements, which are arranged in
a mounting plane in a rectangular frame having a longitudinal
direction and a transverse direction, are aligned in the
longitudinal direction such that they are parallel to one another,
and are shaped in the same way and orientated in the same way. The
relevant profile element has an L-shaped or V-shaped cross section
with at least two limbs that meet in a peak, with the peaks
pointing in the transverse direction, and the spacing between
profile elements that immediately follow each other is chosen such
that there is no rectilinear passage between them.
[0007] As will be described in more detail further below, this
realizes a penetration protection against airborne projectiles
coming from any directions while having a high mechanical load
capacity.
[0008] In a preferred embodiment, the two limbs of the relevant
profile element meet in the peak at an angle that ranges from
80.degree. to 110.degree. and is preferably 90.degree. (right
angle). The advantage over other angle ranges and over rounded
embodiments, for example arc-shaped or wave-shaped profile
elements, is that primarily effective perforation protection is
achieved with comparatively simple and economic measures, coupled
with a high load-bearing capacity on impact of impact bodies.
[0009] It is furthermore advantageous if, when viewed in the
transverse direction, the spacing which characterizes the overlap
between the leading edge of a profile element and the trailing edge
of the profile element that is located immediately in front of it
is approximately 0.5% to 5% of the total width of the relevant
profile element in the transverse direction.
[0010] A symmetrical embodiment, in which the two limbs of the
relevant profile element have the same dimensions, is particularly
expedient.
[0011] It is particularly expedient and advantageous from a
production-technological viewpoint if the cross section of the
relevant profile element is constant over its entire longitudinal
extent.
[0012] The relevant profile element advantageously has two end
faces, at which it is welded to the frame.
[0013] In a configuration that is particularly advantageous for
reasons of economic efficiency, strength and stability, the
relevant profile element is configured in a unipartite manner and
produced by bending an originally planar steel sheet. The profile
element could, however, for example also be cast in one piece in
the desired contour, that is to say as an L profile. Alternatively,
two elongate, flat and preferably rectangular steel-sheet strips
can also be connected to each other, in particular welded, to form
the profile element. Particularly preferred is in any case the use
of catalogued standard steel profiles.
[0014] The frame is for its part advantageously composed of profile
elements with U-shaped or double-U-shaped (two U profiles that meet
at their base sides) cross sections.
[0015] All the profile elements are expediently produced from steel
and are welded to one another at the connection locations.
[0016] The dimensions of the individual components and the
connections between them are preferably chosen such that the cover
is also configured for both comparatively high static surface loads
and for concentrated dynamic impact loads.
[0017] The easy-to-mount/dismantle cover, prefabricated in modular
units, in the manner of a regular steel protective grid or steel
grid serves as a passive protection apparatus for safety-relevant
components in nuclear plants. The cover is directly arranged on,
adjusted and subsequently attached to the outer shell of a building
over an existing cutout/mounting opening. When required, for
example for repair works or to exchange defective components inside
the building, the protective grid can be dismantled and
removed.
[0018] The grid structure is configured and dimensioned in a manner
such that it ensures a sufficient air-flow cross section for
unimpeded operation of the cooling unit while being active as a
full protective barrier in order to protect the safety-relevant
cooling system installed in the building structure against
potential intruding hard and also deformable projectiles, which can
occur for example during a tornado. The proper functioning of the
specially configured steel gridwork system was mathematically
proven. It satisfies all defined criteria/requirements that must be
taken into account when configuring protective barriers against
impacting standard projectiles as are defined, for example, in the
Regulatory Guide 1.76 by the U.S. Nuclear Regulatory Commission
(NRC) for the protection against tornado missiles. The protective
barrier accordingly protects against penetration and
perforation.
[0019] Counted among the advantages of the construction are also
the simple pre-fabrication in the workshop, the short installation
time on the construction site and the simple dismantlability of the
steel construction in the event of repair works or component
exchange.
[0020] Other features which are considered as characteristic for
the invention are set forth in the appended claims.
[0021] Although the invention is illustrated and described herein
as embodied in a protective cover for a ventilation opening, it is
nevertheless not intended to be limited to the details shown, since
various modifications and structural changes may be made therein
without departing from the spirit of the invention and within the
scope and range of equivalents of the claims.
[0022] The construction and method of operation of the invention,
however, together with additional objects and advantages thereof
will be best understood from the following description of specific
embodiments when read in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0023] FIG. 1 is a diagrammatic, plan view of a protective cover
for a ventilation opening according to the invention;
[0024] FIG. 2 is a perspective, detail view of the cover according
to FIG. 1;
[0025] FIG. 3 is a cross sectional view through the cover according
to FIG. 1 and taken along the section line III-III of FIG. 1,
together with a few surrounding building components to which the
cover is attached;
[0026] FIG. 4 is an illustration of detail A from FIG. 3; and
[0027] FIG. 5 is a perspective view of a part of a plant space of a
nuclear-engineering plant with two ventilation openings in the
ceiling that are secured in each case by the cover according to
FIG. 1.
DESCRIPTION OF THE INVENTION
[0028] Identical parts or parts with identical action are provided
with the same reference symbols in all figures.
[0029] The protective cover (in short: cover) 2 illustrated in
FIGS. 1 to 3 serves as a passive protection apparatus for a
ventilation opening 4 in a plant space 6 of a nuclear-engineering
plant, in particular a nuclear power plant. It contains a frame 10
that is formed by four profile elements 8 composed of steel with in
each case a U-shaped cross section. Limbs 12 of the profile
elements 8 point--as can be seen clearly in FIG. 3--in each case to
the outside. Mutually abutting profile elements 8 are welded
together in corners 14, which are cut for a miter joint. The frame
10 has the shape of a rectangle with a longitudinal side 16 and a
transverse side 18. The terms longitudinal side and transverse side
are used here merely to uniquely identify the directions and
possess no implication whatsoever with respect to the relative
lengths. That is to say that the transverse side 18 can, in a
deviation from the illustration in FIG. 1, potentially also be
longer than the longitudinal side 16. A longitudinal direction 20
and a transverse direction 22 are defined accordingly. The frame 10
is subdivided into a plurality of subframes--five pieces in FIG.
1--using a number of profile elements 24 made of steel, which are
aligned in the transverse direction 22 and have in each case a
double-U-shaped cross section. The limbs of the profile elements 24
point in this case to the outside in the direction of the
transverse-side profile elements 8 of the outer frame 10. At the
end faces, the profile elements 24 are welded together with the
longitudinal-side profile elements 8 of the outer frame 10. It is
also possible not to subdivide the frame 10 into subframes if the
longitudinal sides 16 are sufficiently short.
[0030] As can be seen in FIG. 3, the frame 10 of the cover 2, after
it has been mounted, lies on the edge or the mounting surround of a
corresponding ventilation opening 4 in a building wall 26, in
particular a ceiling wall. This refers in the present case to a
building's exterior ceiling, but could also be a building's
exterior wall or an inner wall or inner ceiling with comparable
requirements. The cover 2 is fixed, in particular screwed using
thread bolts 30, to the building wall (here: building ceiling) 26
via an outwardly directed extension arm 28 that is welded to the
profile elements 8 of the outer frame 10. To this end, the building
wall 26 can be provided with corresponding anchor plates or the
like.
[0031] Arranged inside the relevant frame 10 or subframe are a
plurality of elongate profile elements 32 made of steel, which are
aligned in the longitudinal direction 20 such that they are
parallel to one another, and are shaped in the same way and
orientated in the same way, with the profile elements 32 being
welded at their end faces to the transverse-side U-shaped profile
elements 8 or to the double-U-shaped profile elements 24. The
relevant profile element 32 has in the exemplary embodiment an
L-shaped cross section which is constant over the entire
longitudinal extent, with two straight limbs 36 of identical limb
length, which meet in a peak 34 at a right angle) (.alpha.=90), as
can be seen most clearly in FIG. 3 or FIG. 4. The relevant profile
element 32 is formed from a catalogued right-angled steel profile
or is formed from two welded-together metal-sheet strips.
Alternatively, the profile element 32 is formed from an originally
rectangular, planar steel sheet that was bent at a right angle
along its central longitudinal line such that, viewed in the cross
section, the peak 34--or, viewed over its entire longitudinal
extent, the corresponding leading edge--is formed. The peaks 34 of
all the profile elements 32 are arranged on a common imaginary
straight line and point in the same direction, in this case in the
transverse direction 22 toward one of the longitudinal-side profile
elements (hollow profiles) 8 of the frame 10.
[0032] The spacing a--viewed in the transverse direction
22--between the profile elements 32 that immediately follow each
other is selected to be the same size for all the profile elements
32 of a subframe or frame 10, specifically in a manner such that
there is no rectilinear passage between them. This means, according
to the detail view in FIG. 4, that the profile elements 32 are
attached to the profile elements 8 or 24 of the frame or subframe
in a manner such that they are stacked or nested one within
another. The overlap between two adjacent profile elements 32 is
here preferably chosen such that the spacing b between the peak 34,
or the leading edge, of a profile element 32 and the trailing edge
38 of the profile element 32 in front of it is merely of the order
of magnitude of the thickness of the steel sheet used to produce
the profile elements 32 and is approximately 1% to 5% of the
overall extent (=spacing c between leading edge 34 and trailing
edge 38) of the relevant profile element 32 in the transverse
direction 22.
[0033] In addition, covering struts 42, which extend in the
transverse direction 22 with regular spacings relative to one
another and span over the profile elements 32, can be mounted on
the outside 40 of the cover 2 and be welded to the profile elements
32 at the contact locations. The covering struts 42 are formed for
example by round steel elements with a diameter of 20 mm to 30
mm.
[0034] This realizes penetration protection against projectiles
that strike the cover from the outside from different flight
directions and invade the intermediate spaces between the profile
elements 32, as is indicated in FIG. 3 by way of trajectories 44.
In addition, the free flow cross section for the air exchange
between the outside 40 (exhaust-air zone) and the inside 46 of the
cover 2 is kept as large as possible, while the number and the
extent of direction deviations to which the passing air flow is
subjected is kept comparatively small. Thus, the air exchange can
be markedly effective despite the realized full-protection barrier.
On account of the chosen dimensions of the individual components,
it is also possible, if required, to support comparatively large
static and dynamic impact and area loads.
[0035] The cover 2 can of course be used not only for ventilation
openings 4 in the building complex of a nuclear-engineering plant,
but also in diverse other buildings, in which the above-described
properties are advantageous.
* * * * *