The present invention refers to an nonstick equipment, particularly applicable to load compartments for iron ore of the cargo train wagon kind or others, and this nonstick equipment is formed by an nonstick film loosely disposed inside the load compartment, on the inner bottom surface of this compartment and beneath the iron ore load and by a support structure cooperating with the nonstick film such that upon unloading it captures this nonstick film and separates it from the unloaded iron ore. Description of the state of the art

The adherence of granular or pulveriform material during handling, transport and storage is common, principally in a humid environment. In the specific case of mineral coal transport, it is noted that this material sticks to the bottom of the compartments used for transport such as wagons, containers, trucks.

In the rainy period, there is great difficulty in maintaining a performance in the unloading of mineral coal transported by railways. This is because the fine material, when wet, and after being subjected to the natural trepidation of the railway transport, easily adheres to the bottom of the wagon, creating compact blocks which can only be withdrawn by water jetting and manual intervention. Hence, to withdraw the material stuck to the compartment, the entire process of unloading is paralyzed.

This kind of problem has adversely affected both the company receiving the raw material and the company in charge of transport from fulfilling its volume and billing targets. The company receiving the coal, upon paralyzing its unloading to clean the material stuck to the transport compartment, has a dramatic drop in the empty wagon return rate, an indicator which is monitored by the railways at all times. With the fall in the unloading rate and with a view to keeping the network uncongested, the scheduled lots are canceled by the railways planning sector. Accordingly, the railways' outflow comes to a standstill, the Port fails to open up space in its yard and the client has to afford the expenses of accommodation, equipments and manpower to withdraw the stuck product, besides the "demurrage" of ships not docked due to lack of space. In other words, the operating and financial impacts are enormous for all.

Some resources for trying to prevent or minimize this adherence of the material in the transport compartment are already known in the art. Among them, we may cite an epoxy coating (Interzone 954 modified) made of two components, designed to provide protection in a single application and which offers resistance to the loss of cathodic bonding. To apply this product, it is necessary to jet-clean the internal surfaces of the wagon and cure time of 24 hours before loading any material. Therefore, due to the lengthy time for immobilizing the wagon and the low durability of the product, this alternative is economically unfeasible.

Another known resource is the application of an nonstick humidity reducer made of functional epoxy resins (liquid polymer) inside the transport compartment. For this application to have satisfactory results, it is necessary to withdraw the impurities from the wagons and the product must be applied manually. Though low in cost, the low durability generating frequent immobilization of the wagon makes this option unfeasible.

Also known is the application of an nonstick blanket inside the transport compartment. This blanket is formed by a synthetic tape impregnated with silicon nonstick and adhesives disposed on one side of the blanket which has low attrition co-efficient and high resistance to traction. Applying this blanket also requires fully withdrawing the impurities manually from bottom of the wagons, hindering the use thereof due to wagon downtime which cleaning and application require. Document UM 8602559-7 describes an nonstick plastic bin for carding vehicles and various equipments. This bin is formed by various nonstick plastic plates, fastened to the flooring, ribs, rear lid and front lid of a conventional bin. Although it can be adapted for the inside of a cargo wagon, this type of coating consists of a definitive solution, as it requires mechanical fitting of the plates for the entire fleet of wagons. Additionally, the problem of adherence of the powder or granule load is not solved, principally in the case of dry mineral coal.

Document PI 0801438-8 refers to a shield carpet made of rubber for dump trucks and cargo train wagons. This carpet consists of a double-layered rubber. On the inside there are disposed screens formed by steel webs. Though made of elastomer material, the function of this carpet is to protect the inside of the bin of trucks and train wagons and nothing is disclosed regarding its use to prevent adherence of materials inside these load compartments. Additionally, the objective of the disposition of the screens made of steel webs inside this carpet is to assist the rubber to absorb impact inside these compartments.

Document US 4,425,381 describes a method for improving the unloading of bulk mineral loads of trucks, trains, silos and transporters. This method consists of the systematic covering of the walls of the load compartment with nonstick material such as, for example, tetrafluoroethylene, in the form of powder or pulverized solution. This nonstick material, jointly with an anti-freeze material, is constantly applied during unloading of the bulk material. Besides requiring a structure for applying the nonstick material at the unloading site of the material, this method also has the disadvantage of applying a material to the load which, albeit a wax, may contaminate it. Document WO 99/50162 refers to a method for withdrawing adhesive material from load compartments. A support surface composed of a flexible plate is fastened on the inside of a train wagon, more precisely to the lower surface of the wagon, so as to cover this surface and to extend to a certain height of the side walls, forming rounded corners to prevent the attachment of mineral. The mineral is loaded into the wagon containing this support surface. During unloading of the material, the wagon is rotated on its longitudinal axis and the support assists to expel mineral that tends to attach itself to the corners of the wagon. This support surface is fastened to the wagon by multiple screws, meaning the quick withdrawal thereof for use in another wagon is unfeasible, so this support is applied definitively in the wagon.

Objectives of the invention The objective of the present invention is to provide an nonstick equipment applicable to load compartments for iron ore which prevents the mineral from attaching itself to the load compartment during the unloading operation of this mineral.

Another objective of this invention is to provide an nonstick equipment applicable to load compartments which is detachable from this load compartment at the end of each unloading of material to be re-used in another load compartment to be loaded.

Brief description of the invention

The object of the invention is an nonstick equipment applicable to load compartments for iron ore, the nonstick equipment comprising an nonstick film loosely disposed on the inside of the load compartment between the load compartment and the iron ore and a support structure cooperating with the nonstick film so as to separate it from the iron ore during unloading of the load compartment. Summary description of the drawings The present invention will now be described in further detail based on an example of execution represented in the drawings. The drawings show:

Figure 1 - illustrates a load compartment without the nonstick equipment which is the object of this invention; Figure 2 - illustrates the load compartment of figure 1 with the nonstick film that is part of the nonstick equipment which is the object of this invention;

Figure 3 - illustrates the load compartment containing the nonstick film that is part of the nonstick equipment which is the object of this invention positioned on the cardumper system for unloading the iron ore; Figure 4 - illustrates the load compartment during unloading of the iron ore in the cardumper system.

Figure 5 - illustrates in detail the fall of the nonstick film with the unloading of the mineral and its cooperation with the support structure that is also part of the nonstick equipment which is the object of this invention; and Figure 6 - illustrates the nonstick film detached from the inner surface of the load compartment and supported by the support structure, ready for withdrawal and replacement in another load compartment.

Detailed description of the drawings

According to a preferred embodiment and as can be seen as of figure 1 , the nonstick equipment applicable to iron ore load compartments 20, which is the object of this invention, comprises an nonstick film 1 1 and a support structure 12 cooperating with the nonstick film 11.

As illustrated in figures 1 and 2, the nonstick equipment comprises an nonstick film 11 loosely disposed on the inside of the load compartment 20. This nonstick film 1 1 consists of a plastic film which is disposed, without tethers or fastenings, on an internal surface 21 of the load compartment 20, preferably the bottom surface of this load compartment 20.

Accordingly, when the load compartment 20 is loaded with iron ore, for example, the nonstick film 11 , which is not solidary to the inner surface 21 of the load compartment 20, it is positioned between the inner surface 21 of the load compartment 20 and the loaded iron ore, with the function of preventing contact of this iron ore with the bottom surface of the load compartment 20.

By avoiding contact of the iron ore with the bottom surface of the load compartment 20, the nonstick film 11 prevents adherence of the iron ore in the load compartment 20.

To unload the iron ore, the loaded load compartment 20 is taken to the cardumper system 50 illustrated in figure 3, positioned on a turning table 51 of this system and fastened to hopper chute 52.

The load compartment 20 is then turned 160° around its longitudinal axis for the withdrawal of the iron ore load, as illustrated in figure 4.

Therefore, by the action of gravity, the iron ore detaches itself from the bottom of the load compartment 20 and falls into the hopper 52.

As the nonstick film 1 1 is disposed on the inner surface 21 of the load compartment 20, but is not fastened to this inner surface 21 , upon unloading the iron ore by the cardumper system 50 the iron ore and this nonstick film 11 fall jointly by the action of gravity (figure 3).

However, as already described, the nonstick equipment which is the object of this invention further comprises a support structure 12 cooperating with the nonstick film 11. This support structure 12 is formed by a web of steel cables (figures 3, 5 and 6) fastened to an external portion of the load compartment 20, preferably next to the unloading equipment of the cardumper system 50, and so as to be positioned beneath the load compartment 20 when it turns 160° for unloading the iron ore.

The function of the support structure 12 is to assist and capture the nonstick film 11 from the iron ore during unloading of the load compartment 20, such that this nonstick film 11 may be subsequently applied to another load compartment 20 to be loaded. More precisely, the support structure 12 enables the passage of the unloaded iron ore, but prevents the passage of the nonstick film 11 which is captured by the support structure 12 and withdrawing from the unloading equipment for further use.

Hence, at the end of unloading, the load compartment 20 is fully clean, that is, without the existence of iron ore attached to its inside and the nonstick film 1 is recovered, by way of the support structure 12 (figure 6), to be re-used in another load compartment 20 to be loaded. The cardumper system 50 returns the load compartment 20 to the position of 90° and the nonstick film 11 again falls to the bottom of the load compartment 20. An operator positions a mobile platform between the load compartment 20 and withdraws the nonstick film 11. It is also possible to use a beam hook to withdraw the nonstick film 11 from the bottom of the empty load compartment 20. The load compartment 20 is thus released from the cardumper system 50 for the correct positioning of the nonstick film 11 and new loading of iron ore.

The nonstick equipment which is the object of this invention enables cost reduction with the contracting of additional equipments to clean the compacted product attached to the bottom of load compartments 20. Additionally, this nonstick equipment presents the advantages of reducing costs with accommodation generated by unloading delays; reduces environmental impacts with the waste of water in the cleaning process and use of chemical materials for non-adherence of the mineral in the load compartment; reduces safety risk of operators, since with the use of this nonstick equipment there is no need to enter into the load compartment to detach manually the mineral stuck therein; and increases the unloading rate to approximately 17 load compartments/hour, a performance that is significantly higher than the 2.4 load compartments/hour obtained in the unloading of load compartments under the same conditions, but without using the nonstick equipment which is the object of this invention.

Having described one example of a preferred embodiment, it should be understood that the scope of the present invention encompasses other possible variations, being limited solely by the content of the accompanying claims, potential equivalents being included therein.