OBJECT OF THE INVENTION
[0001] The present invention refers to a mounting system especially designed for tewel closures
in tanks and reservoirs, with which system are attained two fundamental objectives,
on one side, that the elements which make up the closure be easily moved from the
outside up to the point of location of the tewel, with pieces of a relatively reduced
weight and which besides allow their free path by "manholes" existing at the installation,
which in many cases have an amplitude smaller than that of the very tewel in which
the closure is to be located, and on the other side, that the mounting operations
may be carried out in an utmostly rapid mode, minimizing the time of exposure of
the operator to the effects of the environment existing in the reservoir.
ANTECEDENTS OF THE INVENTION
[0002] As it is known, the very nature provided for the closure and the size of the tewels
to be closed causes that, in many cases, the closure cover makes up an object of
a considerable weight, requiring several persons for its handling, to which it must
be added, besides, as previously stated, that in many installations there are tewels
which diameter and in consequence the closure cover shows a magnitude higher than
those of the manholes located to accede to the area of location of the tewel.
[0003] On the other hand and as it is also evident, on the cited tewels as it happens for
instance in the tewels of the primary of the generators of the stream in a nuclear
plant, there exists a radioactive environment which forces to minimize as much as
possible the stay of the operator who is to perform the mounting, in this area, with
the evident objective of minimizing at the same time the risk of his being affected
by such a radioactive environment.
DESCRIPTION OF THE INVENTION
[0004] The system which the invention proposes has been especially designed to solve this
problem at full satisfaction, in its different vertients and is based in the establishment
of a modular structuration for the closure elements, which ease their handling and
transport, as each of such modules offers a volumetry and weight considerably smaller
than those of the closure element in its whole, and that together with a great ease
and promptness of mounting for said modules, up to the point that the tine of installation
does not exceed the three minutes, all of it, obviously, together with some optimal
functional provisions for the system, once implanted in the tewel.
[0005] Therefor and in a more concrete mode, the system preconized is based, as previously
stated, in the modular structuration of the cover that makes up the closure, preferably
on basis of three pieces, though obviously this number will be variable according
to the sizes and global characteristics of the specific closure in each case, being
it provided means of joined-up coupling to such pieces or segments which allow their
prompt mounting on a foldable framework, which adopts an en larged configuration
under transport situation, and opens up in a practically instant mode, thus being
adapted to the configuration of the corresponding tewel.
[0006] In a more concrete mode, said framework is made up by several symmetrical arms, being
every two arms adjacent in-between joined through a couple of connecting rods, articulated,
which allow the adaptation of one over the other or their side separation up to a
certain limit situation. In this way all the arms of the framework remain laterally
united during the transport of same, said framework offering an enlarged configuration
of little width, as from which and after its coupling to the tewel, as hereinafter
seen, said framework may be expanded laterally until affecting the whole nozzle of
the cited tewel.
[0007] Specifically the central arm of the cited framework is riveted on one of its ends
into an articulated linking hinge, which is joined to a small support which in turn
is fastened to the flange of the tewel by means of bolts provided with a rapid coupling
system, of the bayonet type.
[0008] These arms of the framework, at their bottom face, incorporate a series of appendixes,
as a hook, in which are susceptible of a successive coupling the various modules or
segments of the very cover, each of which shows joined-up coupling means to the adjacent
ones, materialized in shafts and complementary holes, so that this joined-up coupling
is attained simultaneously with the very implantation of such segments over the framework.
[0009] The last segment to be installed will duly incorporate solidary to same, a diaphragm
or membrane, with which it will be attained the tightness of the closure and which,
after the implantation of this latter segment on the framework, will be duly coupled
to the rest of the segments that make up the cover, acting the very diaphragm as a
union link on the side between same.
[0010] This mounting having ended, it will be enough with taking down the framework-modular
cover assembly over the nozzle of the tewel, and finally proceed to the definitive
fastening of the framework to the latter, by means of bolts similar to those used
for the anchoring of the support of the hinge and located at the free ends of each
of the arms that participate in the structure of such a framework.
[0011] From the structuration described it is deducted the ease of transport not only for
the framework but also for the modules or segments of the cover, the easy, practically
instant transformation of said framework towards the operative situation on the tewel
and as well the easy and prompt implantation on the framework of the various segments
that make up the closure cover which, due to the existence of the joined-up means
that relate them, remain perfectly aligned and interrelated.
DESCRIPTION OF THE DRAWINGS
[0012] To complement the description being made and in order to help to a better understanding
of the characteristics of the invention, it is enclosed to the present specification,
as an integral part of same, a set of drawings in which with an illustrative and not
limitative character, the following has been represented:
Figure 1.- Shows a plan view of the framework which participates in the mounting system
for closures of tewels in installations of nuclear plants which makes up the object
of the present invention.
Figure 2.- Shows a plan view of the same framework, which now appears in an operative
or extension situation.
Figure 3.- Shows a profile of the said framework.
Figure 4.- Shows a modular profile piece division of the segments that make up the
closure cover.
Figure 5.- Shows a profile of the membrane or diaphragm which cooperates with the
segments of the previous figure in the conformation of the cover.
Figure 6.- Shows the first mounting sequence with the system preconized and in accordance
with an example of practical performance, in which the closure is intended to the
tewels of the primary of the generators of steam of a nuclear plant.
Figure 7.- Shows a view similar to that of the previous figure, after the implantation
of the framework.
Figure 8.- Shows the same view after the coupling to the framework of the first segment
of the cover.
Figure 9.- Corresponds to the following sequence, in which there appears coupled the
second segment of the cover.
Figure 10.- Shows again the same view, now with the cover fully mounted and in phase
of adaptation to the various segments of the membrane solidary to the last of them.
Figure 11.- Shows, as per a view similar to that of the previous figures, the same
assembly with the cover perfectly finished, fastened to the framework and in take
down situations, together with the latter, over the corresponding tewel.
Figure 12.- Shows, finally, a view of the anchoring system provided between the framework
and the tewel.
PREFERENT EMBODIMENT OF THE INVENTION.
[0013] On view of these figures, it can be seen how the mounting system for tewel closures
preconized is based in the use of a foldable framework made up of a central arm (1)
and two couples of side arms (2-3-2ʹ-3ʹ) being all these arms joined in-between through
couples of articulated connecting rods (4), being all these arms, through the cited
connecting rods, capable of adapting each other as shown in figure 1, determining
a minimal volumetric occupation for the transport of same, or being extended in
a way that the ends of such arms (1-2-3) remain located over an imaginary circumferential
trace (5), dimensionally coincident with the nozzle of the tewel.
[0014] The very cover or closure is made up by means of a plurality of segments (6-7-8)
as shown by figure 4, provided in their adaptation partitions with small shafts (9)
which, passing through holes operatively made in the adjacent modules, determine the
joined-up coupling between them, in a mostly rapid and simple mode, and with a correct
and specific relative positioning between them.
[0015] These modules (6-7-8) are intended to be fastened to the framework (1), after the
fastening of the latter to the nozzle of the tewel, to which purpose such a framework
incorporates on its faces of reception of such segments, small appendixes in the
mode of hooks (10)which facilitate such a coupling.
[0016] The very cover or closure is complemented with a membrane (11), which is kept unmovably
fastened to one of the segments, concretely to the segment (8) which is to be implanted
over the framework (1) in the last stage.
[0017] The central arm (1) of the framework, on one of its ends and with the cooperation
of a hinge (12), is join ed by articulation to a small support (13), transverse,
provided with holes (14) at its ends for its fastening to the nozzle of the tewel,
previously to the coupling of said framework of the modules which make up the cover,
counting, besides, all the arms (1-2-3) on the framework on their ends, with other
holes (15) for the definitive fixation to the tewel of the assembly, after the mounting
of the cover, as will be seen later on.
[0018] In accordance with this structuration the mounting is started with the temporary
disposition on the nozzle (16) of the tewel, of an element of protection (17) which
sets forth an also temporary closure of same. Afterwards and after the adequate transport
of the framework (1), and of the modules or segments which make up the cover, near
the tewel, which is easily performable due to its modularity, that is, due to the
reduced weight and volume of each of its elements, the support (13) is fastened to
the nozzle of the tewel, so that the framework (1) in its whole is susceptible of
tilting with respect to such a nozzle, situated in the position shown in figure 7,
under which it remains under the conditions of receiving, by simple coupling, to the
first segment (6) of the cover, as shown in figure 8, afterwards to the second segment
(7) of the cover, as shown in figure 9 and finally to the third and last segment (8)
of the cover, as shown in figure 10, which segment bears the membrane (11), which
will be adapted to all the modules or elements that integrate the cover, as in turn
is shown in figure 11.
[0019] Immediately after the take down of the framework-cover assembly takes place, in
accordance with the arrow shown in figure 11, until this assembly is coupled to the
nozzle of the tewel, at which time the fixation of such an assembly is complemented,
concretely through the end holes (15) of each of the arms that participate in the
framework.
[0020] This fixation is also carried out in a mostly rapid and simple mode, concretely with
the cooperation of bolts (18), shown in detail in figure 12, and which by means of
a system of bayonet are coupled to bushings (19) duly implanted in the sine of the
flange (20) which normally the nozzle of the tewel is provided with, or to devices
designed to that purpose in case the tewel has not a flange available.
[0021] This way it is obtained an easy transport of the elements which participate in the
closure of the tewel, up to the area of implantation of same, that is, until the cited
tewel, as well as a latter and rapid mounting of same, with a real time of installation
which does not exceed 3 minutes.
[0022] It must also be highlighted that this mounting system admits deviations in the real
position of the drills of the flange (20), as well as deviations in the real profile
of the tewel, which consequently cooperates fundamentally to facilitate the mounting
process.
[0023] Finally, it must be cited that, within a preferent example of practical embodiment
for the mounting system, the arms of the framework will be obtained in aluminium,
to lighten its weight, whilst the hinge, the axles and bolts will be of steel, like
the bushings inserted in the flange, for the coupling by bayonet of said bolts,
being the membrane obtained in the most ideal material to attain the tightness pursued
through same.
1.- Mounting system for tewel closures in tanks and reservoirs which, having the purpose
of easing the transport of the elements which make up the closure until their place
of definitive location and of minimizing the time necessary for said mounting within
margins reducing to the maximum the risk for the operator versus the effects of the
environment of the area, is essentially characterized in that it is based in the
combined use of a flodable framework and a cover or modular closing element, assisted
by the corresponding tightness membrane, in a way that said framework under folding
situation, adopts an enlarged configuration, which reduces its volumetry, the same
as the modulation of the cover reduces the effective volumetry of each of its parts
and having it been provided that said framework counts on means for the rapid coupling
of the segments that make up the cover, that such segments count at the same time
on means of intercoupling, which establish the relative exact position among them,
that the framework be provided with means of link, initially hinged to the nozzle
of the tewel, prior to the mounting of the segments of the cover, and of a definitive
unmovable fixation to such a nozzle of the tewel, after the mounting of the modules
of the cover and its corresponding membrane.
2.- Mounting system for towel closures in tanks and reservoirs, as per the previous
claim, characterized in that the framework is made up as from a plurality of arms,
articulately linked two to two, with the cooperation of couples of connecting rods,
which central arm is joined at one of its ends and through a hinge, to a small fixation
support to the nozzle of the tewel, whilst at the other end of this arm and in both
ends of the remaining arms, are located holes for the in tegral fixation of the support
of the tewel, after the mounting of the cover.
3.- Mounting system for tewel closures in tanks and reservoirs, as per the previous
claims, characterized in that the modules which make up the cover are provided with,
at their faces of side adaptation, means joined-up, which establish their right relative
positioning, whilst at the face of the framework which corresponds to the reception
of such modules are established small appendixes like hooks, which allow the coupling
to the framework of such segments.
4.- Mounting system for tewel closures in tanks and reservoirs, as per the previous
claims, characterized in that the tightness membrane is solidarized to the last module
of the cover, which are fastened to the framework, as from which mounting is established
the definitive fixation of same to the rest of the modules, by simple coupling to
the surface of same.
5.- Mounting system for tewel closures in tanks and reservoirs, as per the previous
claims, characterized in that the means of rapid coupling to the nozzle, not only
at the beginning of the small hinged support to the framework but also after the mounting
of the cover of all of them to each of the arms of said framework, consist in bolts
which cross holes of said support and arms, and which are coupled by bayonet or any
other type of bolt in the sine of bushings, operatively set forth in the flange located
in the nozzle of the tewel, or in other devices designed to that purpose.
6.- MOUNTING SYSTEM FOR TEWEL CLOSURES IN TANKS AND RESERVOIRS.