EP2578371A1

EP2578371A1 - Dismountable plant for concrete manufacture

Info

Publication number: EP2578371A1
Application number: EP12187503.3A
Authority: EP
Inventors: Genesio Setten
Original assignee: Setten Genesio SpA
Current assignee: Setten Genesio SpA
Priority date: 2011-10-06
Filing date: 2012-10-05
Publication date: 2013-04-10
Anticipated expiration: 2032-10-05
Also published as: ITMI20111814A1; EP2578371B1

Abstract

Plant for the manufacture of concrete comprising multiple silos (B) for the loading of cement and of inert materials, scales (3) for the dosing of cement and of inert materials supplied by said silos (B) through belt- and screw- conveyors (5, 6), a mixer (4) supplied by said dosing scales (3) and apt to manufacture the concrete, a water tank and any additive tanks. The silos (B_g, B_s) of the inert materials consist at least in part of a plurality of containers (1), stacked with no permanent, mutual-fastening means, each one of such a size as to be able to be road-transported, full of inert materials, through an ordinary means of transport. A crane (C) - permanently present in the plant and also used for the assembling/disassembling of the same - provides to the handling of said loaded containers (1) from said means of transport to said silos (B_g, B_s) and vice versa when said containers are empty.

Description

FIELD OF THE INVENTION

The present invention refers to a plant for the manufacture of concrete, and in particular to a moving plant, i.e. a plant apt to be disassembled and reassembled from one building site to another quickly and easily.

STATE OF THE BACKGROUND ART

As known, in the building industry very large use of concrete has been made for a long time for the construction of foundations, structural elements, slabs, etcetera. In the case of individual buildings of low volume, concrete is normally purchased from third parties' fixed plants for concrete manufacture, often installed in the proximity of quarries for the manufacture of inert materials, which concrete is transported by road to the building site in concrete-mixer lorries.
In the construction of buildings of a larger volume, resorting to third parties' plants for concrete manufacture is not preferred. As a matter of fact, waiting times for concrete-mixer lorries are not easily programmable according to the activities of the building site, the quality of the supplied concrete is often not suited to the request and finally costs are variable and depending on market conditions. For these reasons, in the case of large buildings the habit has become widespread to build fixed plants for concrete manufacture on the same building site, or immediately nearby, so as to be able to have a dedicated and controlled production which is perfectly suited to building site requirements.
However, concrete manufacturing plants of the currently known type are mainly fixed plants built with techniques of traditional, welded metal structural work and are expensive, have a large bulk, require long mounting times and finally, at the end of the use thereof, are not apt to be disassembled conservatively and are hence disposed of as scrap iron.
In US-6,832,851 a partly moving plant is proposed, wherein at least part of the plant components are modularly prefabricated using international-standard-sized container structures, as building elements and/or to hold equipment. Although with this type of plant transport/shipment operations may actually be carried out in a short time, such advantage is at least partly cancelled by the fact that assembling and disassembling operations are complicated by the need to adjust the various pieces of equipment of the plant to the standard size of the containers, by providing joints or connections which increase the costs thereof and make the use thereof less functional. Moreover, the mutual attachment of the individual containers is not sufficient to guarantee the mechanical stability of the plant and additional support, fastening and strengthening structures of the traditional type must hence be provided..
Also these types of plants hence have - even though to a smaller extent - the problems of large bulks and long assembling/disassembling times of the fixed plants.
Finally, all known plants are in any case affected by the significant disadvantages connected with the current transport modes of inert materials, which will be dealt with more in detail in the following.
As a further drawback, all the above-mentioned known implants are characterised by high environmental impact and pollution and hence require thorough decontamination of the occupied soil at the end of the works.
For all the reasons set forth above this type of fixed or partly moving plants on the building site are used today only on building sites in which really large volumes are built, wherein the costs of the concrete manufacturing plant can be amortized and, preferably, on building sites not included in already densely populated areas, due to the pollution problems highlighted above.
As mentioned above, particularly critical in this type of known plants is the management of inert materials. As a matter of fact, said materials are transported loose on lorries from the quarry to the building site plant where they are emptied out onto the ground on the yard; from here, with mechanical shovels or with other known lifting and transport means - having a high degree of complexity and large bulk and which hence require large manoeuvring spaces - they are loaded onto loading hoppers of conveyor belts, for the filling of fixed storage silos. Said storage silos of inert materials are located above the dosing scales of the inert materials and of the concrete and above the mixers meant for concrete forming, through a mix with water and additives of such elements. It is hence evident how this type of arrangement requires very large spaces for transport means manoeuvre and the temporary storage of the inert materials, as well as for the arrangement of the belt conveyors for the loading of the silos, and it is furthermore evident how this type of arrangement determines a high degree of dust and noise pollution in the surrounding environment.

PROBLEM AND SOLUTION

The problem at the basis of the invention is hence that of proposing a new type of concrete manufacturing plant, which allows to simultaneously solve the problems mentioned above of the known-type plants, and in particular which exhibits: versatility and adjustability to the available spaces; reduced bulk; quick and safe mounting system based on modular elements; low level of dust and noise pollution in the management of the inert materials; closed-circuit system for the washing and recovery of concrete residues; finally, an actual opportunity for the moving and reuse of the plant in situations which have different availability of space and varied requirements of concrete manufacture.
These objects are achieved through a concrete manufacturing plant provided with the features defined in the herewith attached claim 1. The dependent claims describe further preferred features of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the concrete manufacturing plant according to the present invention will in any case be better evident from the following detailed description of a preferred embodiment of the same, given purely as a non-limiting example and shown in the attached drawings, wherein:

fig. 1 is a schematic, side-elevation view of a moving concrete manufacturing plant, according to the present invention;
fig. 2 is a section view along a vertical plane, marked II-II, of the moving concrete manufacturing plant of fig. 1;
fig. 3 is a section view along a horizontal plane, marked III-III, of the moving concrete manufacturing plant of fig. 1. For ease of reading such drawing is shown on the same plate and in the same scale as fig. 1 and furthermore on a separate, enlarged-scale plate;
fig. 4 is a section view similar to fig. 2, of an alternative embodiment of the concrete loading silos;
figs. 5A, 5B, 5C and 5D are section views, similar to the enlarged-scale one of fig. 3, which show some different possible embodiments of the concrete manufacturing plant of fig. 1;
fig. 6 is a vertical, diametral section view of a modular container for inert materials used in the moving concrete manufacturing plant of fig. 1;
fig. 7 is a top plan view of the modular container for inert materials of fig. 7; and
fig. 8 is an enlarged perspective view, from the outside, of the detail of the modular container of fig. 7 enclosed in a circle, which shows one of the fastening ribs of said modular container.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As will be clear from the following description, the moving concrete manufacturing plant according to the present invention departs from the traditional management mode of inert materials described above, fully eliminating the transport and loose loading of the same and the moving thereof on the ground in the plant yard, and adopts instead a transport of the inert materials in moving and stackable containers specifically designed for the purpose. As a matter of fact, such containers are suited to be loaded on a standard lorry for the transport from the quarries to the plant and to be mutually stacked there to thus form loading silos, or stacked on silos already prepared for providing to the loading thereof through a crane, all as better detailed in the following, which crane - also in this case in a fully innovative way with respect to known concrete manufacturing plants - forms an integral part of the plant of the invention.
A first embodiment of the plant is shown in figs. 1-4. In its essential lines, the plant comprises a rectangular concrete foundation bed A, cast in situ or formed by means of prefabricated blocks, whereon a crane C and a plurality of silos B are arranged and suitably anchored, said silos B containing the solid matter for concrete forming, i.e. cement and inert materials. In the embodiment shown in figs. 1 and 3, silos B and crane C are arranged aligned in a single row, crane C being arranged between two silos B_c meant to contain cement (left of crane C in fig. 1) and five silos meant to contain the inert materials (right of crane C in fig.1), and precisely two silos B_s containing sand and three silos B_g containing gravel.
Each one of the seven silos B is supported by a basic reticular framework F, preferably of the type with modular elements which can be assembled by means of screw joints or pin joints, so as to make the assembling and disassembling operations thereof quick and easy. The height of the reticular frameworks F is sufficient for housing within all the plant services, namely: transport systems of the cement and of the inert materials to the mixer; dosing scales for cement and inert materials; mixer; water tanks and additive tanks; loading area of concrete-mixer lorries and hauled concrete pumps; washing devices of such machines; devices for the recovery, separation and storage of the dirty wash waters; access ladders to the different levels of the reticular frameworks F and to crane C; storage areas and offices.
According to a main feature of the invention, silos B_g and B_s meant to contain the inert materials - unlike what happens in conventional plants where such silos consist of monolithic cylindrical tanks - are of a modular type, and precisely they consist of a plurality of containers 1 of a height equal to or close to the width thereof, which are mutually stacked until they reach the desired silo capacity. Alternatively, it is nevertheless also possible to use monolithic silos having the same outer configuration of the above-said containers, and to then load said silos of inert materials stacking thereon one or more of said loaded containers.
The structure of containers 1 for inert materials of the present invention is clearly visible, in section and in top plan view, in figs. 6 and 7 and consists of a sturdy outer cylindrical body 12 to the lower inner part of which an upside truncated cone 13 is welded which ends with an opening 14, suitably recessed with respect to the base of said cylindrical body 12. The surface of truncated cone 13 hence forms an inner hopper bottom of container 1 through which the gravel or sand loaded in the container is unloaded by the same through opening 14. Said opening is furthermore provided with a diaphragm-type closure means which can be actuated and adjusted from the outside, of the type known per se and not shown in the drawings, which is maintained in a closed position during the transport of container 1.
As a matter of fact, the containers 1 for inert materials of the present invention are used, according to a fully original feature of the present invention, not only for the forming of silos B, but also for the transport of inert materials from the production quarry thereof to the concrete manufacturing plant. As a matter of fact, containers 1, after the opening 14 thereof has been duly closed, are filled directly in the quarry with gravel or sand and then loaded onto lorries and transported to the concrete manufacturing plant of the invention. Here containers 1 are taken from the means of transport directly by crane C and hence positioned on the reticular framework F, in the positions provided for this purpose. In order to allow the swift transportability of containers 1, the dimensions thereof must hence be such as to be able to be transported by road, loaded with inert materials, through an ordinary means of transport. Preferred dimensions are the ones indicated in the drawings, where one can see that container 1 is comprised within a cube having a side of 2.4 metres.
After having arranged on reticular framework F a first series of basic containers 1, subsequent containers 1 are stacked one on top of the other to form silos B of the desired height. By the term "stacked" or "stackable" it is meant to define a condition in which containers 1 simply rest on one another, with no permanent mutual-fastening means, the stability of the silo formed by multiple containers being entrusted to the shape of container 1 and to the weight thereof. It is of course possible to additionally provide also quick release devices to make containers 1 temporarily and mutually integral once stacked, which fastening systems may prove necessary only when the plants are installed in areas subject to strong winds or at high seismic risk. In the embodiment shown the silos consist of 6 containers, each one 2.40 m high and of equal diameter. The overall height of silos B is hence over 13 metres, taking into account an overlapping area of about 0.20 m height between stacked containers 1, which allows to achieve the desired stability and tipping-over safety. The closing means of opening 14 of containers 1 after the first one are opened as the containers are arranged in position and the adjustment of the unloading of whole silo B thus formed is accomplished through the closing means of opening 14 of the container 1 of each silo B arranged in the lowest position, i.e. the one resting on reticular framework F.
To improve the mutual stacking of containers 1, the outer cylindrical body 12 thereof, as well as that of monolithic silos 11 which will be dealt with shortly, ends above with a conical edge 15 inclined inwards, which acts as guide and centring for a container 1 arranged on top thereof and, once mounted, it determines the above-said overlapping area between adjacent containers which already allows to have an optimal safety level, with respect to the stability of the modular silos of the invention, even in the absence of mutual-fastening devices.
Finally, on the upper edge of cylinder 12, as shown in the detail of fig. 8, external cavities 16 (four in the embodiment shown) are furthermore formed in the thickness of the cylinder and on the outer portion of the same, preferably by mechanical machining through material removal, each cavity 16 being provided with a perforated central rib 17, for the easy fastening of container 1 through a multiple-hook lifting system, for example that of crane C.
The modular construction of silos B described above can concern the entire vertical extension of the silo, as indicated in fig. 2, or only a portion thereof, as indicated in alternative embodiment of fig. 4, wherein the lower portion of the silo consists of a conventional silo 11, on the top of which a reduced number (1-4) of containers 1 can be housed which alternatively act either as simple silo reloading means, or as an integral element of the silo. This second embodiment may be conveniently used also for the silos of cement B_c, as a valid alternative to the conventional silos with pneumatic-filling or screw conveyor-filling, when such type of filling is not available or causes dust scattering problems.
The distribution of the different services of the plant inside the same is of course designed depending on the composition of the individual plant, which composition may vary in the arrangement thereof, as shown in the four different embodiments shown in figs. 5A-5D, wherein, however, all the essential plant elements as described above are always present, even though in a varied number and arrangement.
In the embodiment of fig. 1, framework F comprises in height three different portions, namely a lower portion F_b of about 4.40 m height, a middle portion F_m and an upper portion F_t, these last two measuring both about 2.2 m height each and the plant services already listed above consist of and are arranged as follows:

transport systems of cement and inert materials to a mixer, consisting of a screw conveyor 5 and of conveyor belts 6 arranged in the upper portion F_t of reticular framework F, immediately below the outlets of silos S. In the embodiment shown, screw conveyor5 for cement transport has an inclined configuration, to be able to collect the product unloaded from silos B_c which are arranged at different heights from the ground, and occupies also part of the central portion F_m of framework F, while conveyor belt 6 is horizontal, because the outlets of silos B_g e B_s are all arranged at the same height from the ground;
dosing scales 3 for cement and inert materials arranged inside the body of crane C, also in the upper portion F_t of the framework F, and fed by screw conveyor 5 and by conveyor belts 6;
a mixer 4, also arranged inside the body of crane C, in the above-said intermediate portion F_m of framework F, below dosing scales 3 and fed thereby;
a water tank and additive tanks arranged, in a central position, in the lower portion F_b of framework F which supports the inert material silos;
a loading area 2, consisting of a bridge-like base structure of crane C which hence allows concrete-mixer lorries and hauled concrete pumps direct access under mixer 4, so as to make the loading operations of the same as easy, quick and clean as possible;
washing devices for washing concrete-mixer lorries, hauled concrete pumps and mixer 4, in the shape of conventional pressurised-water jets or nozzles, are provided in the same loading area 2 of such machines. In the flooring of said loading area 2, a grid 9 with drain well allows to recover entirely the wash waters and the cement and inert materials transported thereby;
devices for the recovery, separation and storage of the above-said dirty wash waters, also arranged in the portion F_b of framework F which supports the inert material silos, namely in the portion adjacent to crane C. Through such devices it is possible to separate and store separately the different components of the slurry collected through the grid 9 with drain well. Such components are then sent for recycling to mixer 4 in a subsequent concrete-forming cycle;
storage areas of various material for plant operation are formed in the portion F_b of framework F which supports the inert material silos, namely in the part facing towards the plant outside;
access stairs 7 are provided in the base portion F_b of reticular framework F which supports the cement silos B_c, for the purpose of providing access to the area of mixer 4 and to central portion F_m of reticular framework F, wherein the offices for plant control and management are located;
from the arrival area of access stairs 7, i.e. from the area of mixer 4, alternate-flights stairs 8 rise around crane C to provide access to the high portion of the same crane C and to metal inspection catwalks G which are provided at the different levels reported in the drawings.

The plans, the measurements and the dimensions, the number and the contents of the silos, as well as the distribution system of the inert materials, are purely indicative and exemplifying and hence serve solely to illustrate the plant operation. As a matter of fact, in the practical working of the invention there is always a high opportunity for the user to adjust the plant to the specific requirements of positioning, dimensions and accessibility of the mounting site.
From the preceding description it should be clear how the concrete manufacturing plant of the present invention has fully reached all the provided objects. As a matter of fact, the plant provides an extremely reduced space occupation and, in particular, strictly limited to those spaces which are taken up by storage silos, since all the yard spaces meant for the handling of the inert materials have been eliminated and since all plant services are inserted in the same perimeter occupied by the silos. The use of closed containers for the handling of inert materials through crane C furthermore completely eliminates dust and noise pollution, typical of conventional plants. Finally, the simplicity and modularity of the plant allows both extremely fast assembling and disassembling - facilitated by the very presence of crane C within the plant, which hence plays an essential role both in the assembling/disassembling steps and in the running of the plant- and a change of the layout and of the number of the individual plant components, to adjust itself flexibly to the spaces available in the proximity of the building site for the installation of the plant.
All these positive features cause the concrete manufacturing plant according to the present invention to be able to be mounted also in already densely populated areas, and in particular in urban building sites, without causing drawbacks or inconvenience to the workforce meant for the plant nor to the residents of the surrounding buildings, thus allowing greater economy, execution swiftness and quality of the concrete works carried out as well as a reduction of the vehicle traffic otherwise necessary for the supply of the urban building site with concrete coming from external plants.
It is hence understood that the invention must not be considered limited to the particular arrangements shown above, which represent only exemplifying embodiments thereof, but that a number of other variants are possible, all within the reach of a person skilled in the field, without departing from the scope of the invention, as defined in the following claims.

Claims

Plant for the manufacture of concrete, of the type comprising multiple silos (B) for the loading of cement and inert materials, one or more scales (3) for dosing the cement and the inert materials supplied by said silos (B) through belt- and screw-conveyors (5, 6), a mixer (4) supplied by said dosing scales (3) and apt to manufacture the concrete, a water tank and possible tanks for additives, characterised in that said inert material silos (B_g, B_s) consist at least in part of a plurality of containers (1), stacked with no permanent, mutual-fastening means, each one of said containers having such a size as to be able to be road-transported full of inert materials by means of an ordinary means of transport, and in that the plant furthermore comprises a crane (C) for moving said containers (1).
Plant for the manufacture of concrete as claimed in claim 1, wherein each of said containers (1) consists of a cylindrical body (12) having a hopper-shaped inner bottom (13) provided with a discharge opening (14), preferably recessed with respect to the base of said cylindrical body.
Plant for the manufacture of concrete as claimed in claim 2, wherein the discharge opening (14) of said hopper-shaped bottom (13) is provided with a diaphragm closing means which can be actuated from outside the container (1).
Plant for the manufacture of concrete as claimed in claim 3, wherein each one of said containers (1) comprises an upper conical edge (15) inclined towards the inside of the container and integral with said cylindrical body (12), said upper conical edge (15) forming a guiding and centring element for a container (1) stacked on top thereof.
Plant for the manufacture of concrete as claimed in claim 4, wherein each one of said containers (1) comprises, in correspondence of the upper edge of said cylindrical body (12), multiple external cavities (16), each one provided with a perforated central rib (17) for moving the container (1), said cavity (16) and said perforated rib (17) being preferably formed by material removal in the thickness of said cylindrical body (12).
Plant for the manufacture of concrete as claimed in any one of the preceding claims, wherein said silos (B) are supported by a base reticular framework (F), preferably of the type having modular elements which can be assembled by means of screw joints or pin joints.
Plant for the manufacture of concrete as claimed in claim 6, wherein said reticular framework (F) has a height sufficient for housing inside all the plant services.
Plant for the manufacture of concrete as claimed in claim 7, wherein said reticular framework (F) comprises the following portions and corresponding services:
- a lower portion (F_b) comprising: devices for the washing of concrete-mixer lorries and hauled concrete pumps; devices for the recovery, separation and storage of wash waters; access steps (7) to the various levels of the reticular frameworks (F); water and additive tanks; storage-areas;

- an intermediate portion (F_m) comprising: screw conveyors (5) for transporting the cement to the dosing scales (3); offices;

- an upper portion (F_t) comprising: belt-and-screw conveyors for the transport of the inert materials (6) and of the cement (5) to the dosing scales (3).
Plant for the manufacture of concrete as claimed in claim 6, wherein said crane (C) comprises a bridge-like base structure which houses inside therein a loading area (2) of the concrete-mixer lorries and of the hauled concrete pumps.
Plant for the manufacture of concrete as claimed in claim 8, wherein above said bridge-like base structure (2) and inside the body of the crane (C) there are housed, one on top of the other, said scales (3) for the dosing of the cement and of the inert materials as well as said mixer (4).
Plant for the manufacture of concrete as claimed in claim 8, furthermore comprising alternate flights of steps (8) which runs around the crane (C) from the area housing the mixer (4) up to the top of the same crane (C), moreover providing access to intermediate metal catwalks G for the inspection of the silos (B).