LU86577A1 - IMPROVEMENTS IN CONTINUOUS COOLING PLANTS FOR LAMINATED METAL PRODUCTS - Google Patents

Description

f Λ - --------- ------- Α-Λ - »* - ** .. μ BL-3941

j vl | j h K 7 / GRAND-DUCHE OF LUXEMBOURG

! Patent N ° .. V V ^ 7 ', ... . t i Minister! * · # U .¾ jjkj '* of .10 Û9 ..1986 ....................... of Economy and Average Qasses! riZJSt Intellectual Property Service

TOredelltTe -...................-............. I S0 LUXEMBOURG

Patent Application ............................................ ...........................................- JL · .--- ---------------------------------------------------------- -------------- (1) I. Request METALLTTRGIOUES RESEARCH CENTER - CENTRUM VOOR RESEARCH IN DE_____ (2) .METAHJIRGIE ..-- .. AssociatiQn ... sans.J} ut ... lucrative -... Vereniging. zonder. .winstoogmexk

Alrrua Jionta.yer.f..2LQAD ..- Bruxelles.f ^ .B.elgiMue ________________ represented by E.Meuers & E. T. Freulinner. Ina, advice in yropr.ind., (3) 46 rue du Cimetière. Luxembourg, acting as agents _____ deposelnt) ce. — Âi.x mid, 2 nine .... one hundred and four vincrt six ____ (4) at _L5 „_............... ..hours, at the Ministry of the Economy and the Middle Classes, in Luxembourg: 1. this request for obtaining a patent for invention concerning:

Improvements to continuous cooling systems for (5) ..metallic ...... products ... rolled .__________________________________________________ 2. description in language .......-....... .French ._____________________________________ of the invention in triplicate; 3 ............. four ...................-...... drawing boards, in three copies: 4 the receipt of the taxes paid to the Luxembourg Registration Office on .1.0 ..... September 1986 - 5. the delegation of power, dated___Brussels____________________________ on -9 .september-2996-- .: 6. the document having the cause (authorization); declares (s) assuming responsibility for this declaration, that the inventor (s) is (are): (6) .11 ..... Marios ^ .EC0N0MQP.0l ^ Qß ^^ jß / l22J ... JquaijiiareelliSj .. ^ B _- ^ P..2.Q_Liege ...........

.21 ..... Pierre ..... S.IM.QN. ^ .. Au..Long..I> ré ... Jâ.f__B ..... ^ .. 4220..f2haudfontaine = Embourg___________ claimingfat) for the above patent application the priority of one (or more) request (s) of (7) ------------------------- -------------------------- filed in (8) _____-, .............

on (9) --------- “------------------------------------ ---------------------------------------------------------- ------------------------ under N ° (10) ____________ ~ .r. _____________________________________________________________ in the name of (11) __________- = ______________________________________________ elect (elect) domicile for him / her and, if designated, for his / her representative, in Luxembourg________________. 46 .... rue ..... du .... .C2Jne.tièref.Buxemhouxg ________________________ (12) requests (nt) the issue of a patent for the invention for the subject described and represented in the abovementioned appendices, with deferment of this dehyfanceif ___ ^ ___ eighteen ___________________________ months. (13) agent: 7W 'aLt / .......................... — ________________-__________________ (14) y yf 1ï. Deposit Minutes

The aforesaid request for brevej ^ djaéqjtimf has been filed with the Ministry of the Economy and Average Qasses, Service of Property lnj ^ tf ^ fei '& ^^ u ^ rrà) ourg, dated: jq September 1986 OQ f · .-¾¾¾¾ M Pr. The Minister of Economy and Average Qasses, at .ΜL -................. hours 1J; 3 J jQfd.

W! I The head of the intellectual property department, 1 / y A 68007_ / _ EXPLANATIONS RELATING TO THE DEPOSIT FORM.

ii) if applicable "Application for certificate of admission to the main patent, to the application for main patent No ........... Mu ............ (2) enter the surname, first name, profession.

address' of the applicant, when the applicant is a private individual or company name, legal form, address of the head office, when the applicant is a mummy person - (3) enter t /, * BL-3941 Descriptive memorandum filed with support for an application for a patent for invention in Luxembourg C 2370/8609.

METALLURGICAL RESEARCH CENTER -CENTRUM V00R RESEARCH IN DE METALLURGIE,

Non-profit association -Vereniging zonder winstoogmerk in BRUXELLES, (Belgium).

_. .— · b

Improvements to continuous cooling installations for rolled metal products. *

The present invention relates to an installation for continuously cooling rolled metal products, such as steel bars emerging from the finishing stands of a hot rolling mill.

We now know for several years the so-called quenching and self-tempering treatment developed by the applicant to improve the mechanical properties of metal products, in particular concrete reinforcing bars. Briefly recalled this process consists in abruptly cooling and for a limited time, the surface of the bar at the exit of the last stand of the hot rolling mill, so as to form there a layer of martensite and / or bainite then, during 'a \ - 2 - subsequent stay of the bar in the air, to cause an income, called "self-income", of this surface layer under the effect of heat propagating, by conduction, from the interior regions - the heart - uncooled from the bar.

The sudden surface cooling is currently carried out by passing the bar through an aqueous medium, and the process is carefully carried out and controlled in order to supply with certainty products having: the desired properties.

The implementation of this process obviously requires an adequate installation. As a general rule, the installations currently used include, in addition to the actual cooling equipment with its supply and control systems, a first basin for collecting cooling water and a second basin with a cooling tower for cooling. some water. The whole is completed by a set of pumps, filters, valves and pipes, dimensioned so as to be able to ensure high water flow rates, of the order of 4 to 8 m3 per tonne of steel treated.

The construction of such an installation requires significant work on the site of implantation, that is to say the rolling mill; it involves the occupation of a large area of land and it requires high investment. Such an installation sometimes makes it difficult to conduct the process because of the large number of equipment which is involved in the operation. Finally, the installation must often be adapted according to local conditions, which does not allow the delivery of completely completed installations.

The present invention relates to an installation intended to remedy the aforementioned drawbacks. To this end, the invention proposes a compact installation, allowing a significant reduction in the work on the site of implantation, the occupied surface area and the investment costs. It also allows better control of the process and it lends itself to the realization of "turnkey" installations.

* »- 3 - To this end, the installation which is the subject of the present invention is essentially characterized in that it comprises in combination: (a) a tank intended to receive the aqueous cooling medium; (b) above the tank and at a level higher than the level of the aqueous cooling medium in the tank, a plurality of tubular elements, aligned along a common horizontal longitudinal axis, intended to be successively traversed by the product to cool; (c) above the tank and higher than said plurality of tubular elements, means for capturing the water vapor present in the tank; (d) means for supplying said tubular elements with an aqueous cooling medium from the tank; (e) means for supplying said tank with an aqueous medium.

According to an advantageous embodiment of this installation, the capture means comprise at least one fan ensuring a controlled extraction of the vapor released by the aqueous medium which is in the tank.

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Preferably, the fan provides forced suction of air through the "water mist" formed in the tank, so as to evaporate% part of the water and therefore cool the remaining water.

Also according to the invention, the means for supplying said tubular elements in an aqueous medium comprise a pump connected to said tank, as well as at least one pipe putting said pump in hydraulic communication with an essentially horizontal channel arranged parallel to said tubular elements with which it communicates through conduits.

In the context of the invention, said pump is advantageously arranged inside the tank, preferably near the bottom of the latter. In addition, the channel is advantageously located under the tubular elements, with which it communicates by vertical conduits.

- 4 - In a manner known per se, the successive tubular elements are spaced, in the axial direction, by a distance of the order of 20 mm.

Still according to the invention, the entire installation comprising the tank, the plurality of tubular elements with their supply means, and the collection means is housed in a common enclosure communicating with the fan and provided with a inlet opening and an outlet opening for the product to be cooled, these two openings being centered on the longitudinal axis of the aligned tubular elements. To this end, the tank and / or the capture means can themselves constitute parts of said common enclosure.

According to an advantageous feature of the invention, the installation can be mounted immediately at the exit from the last stand of the hot rolling mill, so that the common longitudinal axis of the aligned tubular elements coincides with the exit axis of the products. out of said last rolling stand.

Furthermore, and in a manner known per se, the installation in accordance with the invention is equipped with appropriate means for “measuring and adjusting various parameters characteristic of the process, in particular the flow rate and the temperature of the aqueous medium for cooling the product. .

The invention will now be described in more detail, with reference to the preferred embodiment illustrated, by way of example, in the accompanying drawings, in which Figure 1 schematically illustrates a typical existing installation; Figure 2 shows the principle of a compact installation according to the invention; Figure 3 shows in a plan view (a) and in elevation (b), a preferred embodiment of an installation according to the invention; and the 4 ·.

- 5 - Figure 4 shows a view of this installation, in cross section along line B-B of Figure 3 (b).

In the figures, similar elements have been designated by the same reference numerals and the parts which are not essential for understanding the invention have been omitted.

Referring to Figure 1, a steel bar 1 from a hot rolling mill (not shown) enters a cooling ramp 2, known per se, where it undergoes the sudden surface cooling of the treatment recalled in the introduction . The cooling water evacuated from the ramp 2 is collected in a collection basin 3 from which it is sent, by a pump 4, to a cooling basin 5 equipped with a cooling tower 6. A possible excess of water in the cooling basin 5 is returned by a conventional overflow to the collecting basin 3. The water cooled in the cooling basin 5 is taken up by a pump 7 at high pressure and is returned through filters 8 and devices for measuring and regulating the flow 9, to the supply of the cooling ramp 2. The cooling basin 3 is provided with a supply of fresh water 10, intended in particular to compensate for the losses by evaporation in the cooling tower 6 and to adjust the temperature of the water sent to the cooling ramp 2.

Figure 2 shows schematically the essential characteristics of a compact installation according to the present invention. In this installation, the cooling ramp 11, the water cooling system 12 and the water circulation equipment 13 are assembled in a single assembly. This assembly can be grouped in a common enclosure and thus constitute a cooling group 14 available "key on door". In this cooling group, the water cooling system 12 is connected on the one hand to a fan 15 which extracts the heat in the form of steam and to a make-up water supply 16 which compensates for the water losses due to evaporation and possible leaks - 6- - ^ iii nr tuelles. The apparatus 13 essentially comprises a variable speed pump. The make-up water flow rate is regulated by an apparatus 17, while the flow rate of the variable speed pump is controlled by conventional measurement and adjustment instruments 18.

In Figure 3, there is shown a cooling unit 14 meeting the principles set out in Figure 2, installed immediately at the outlet of the last stand 20 of a hot rolling mill train.

FIG. 3a offers an elevational view, in partial longitudinal section, of the cooling group 14, which shows the cooling ramp 11 made up of successive tubular elements 21 aligned with the outlet axis of the rolling mill. This cooling ramp 11 is located above a tank 22 containing the product cooling water and collecting the water returning from the ramp 11. A variable speed pump 23 is installed in the bottom of the tank 22; it sends the cooling water to the tubular elements 21 via a vertical pipe 24 and a horizontal distribution channel 25, which is itself appropriately connected to the tubular elements 21.

The assembly formed by the tank 22 and the cooling ramp 11 is capped by a hood 26, visible in FIG. 4, intended to capture the water vapor coming from the tank 22. This hood is connected to a fan (not represented) by the conduits 27 visible in FIG. 3b and in FIG. 4.

Figure 4 shows a view of the installation in cross section along line B-B of Figure 3b. Next to the tank 22, there is a compartment 28 housing the motor of the pump 23.

In response to the orders supplied by the measuring and adjusting devices (marked respectively 18 and 19 in FIG. 2), the variable speed pump 23 sends the water from the tank 22, at the required pressure, through the vertical pipe 24 and the horizontal distributor channel 25 to the tubular elements 21. After having cooled the metallic product circulating in these tubular elements, the water returns to the tank 22 where it cools as a result of the aspiration of the vapor by the fan. The water '<therefore circulates in a closed circuit, which reduces consumption. The water level in the tank 22 is kept substantially constant by a conventional water supply not shown in Figures 3 and 4. This water supply can be ten to fifteen times lower than in a conventional installation.

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Claims (6)

1. Installation for continuously cooling a rolled metal product, in particular a steel bar, leaving the finishing stands of a hot rolling mill, by means of an aqueous medium, characterized in that it comprises in combination: (a) a tank intended to receive the aqueous cooling medium; (b) above the tank and at a level higher than the level of the aqueous cooling medium in the tank, a plurality of tubular elements aligned along a common horizontal longitudinal axis, intended to be successively traversed by the product to cool; (c) above the tank and higher than said plurality of tubular elements, means for capturing the steam coming from the tank; (d) means for supplying said tubular elements with a cooling medium from the tank; (e) means for supplying said tank with an aqueous medium. 2. Installation according to claim 1, characterized in that the capture means comprise at least one fan ensuring a controlled extraction of the water vapor present in the tank. 3. Installation according to either of claims 1 and 2, characterized in that the means for supplying said tubular elements in an aqueous medium comprise a pump connected to said tank, as well as at least one pipe placing said pump in hydraulic communication with an essentially horizontal channel arranged parallel to said tubular elements with which it communicates by conduits. 4. Installation according to claim 3, characterized in that the pump is arranged inside said tank, preferably near the bottom of the tank. • 4 * - 9 - 5. Installation according to either of claims 3 and 4, characterized in that said channel is located under the tubular elements, and in that it communicates with these by vertical conduits. 6. Installation according to either of claims 1 to 5, characterized in that the entire installation comprising the tank, the plurality of tubular elements with their supply means, as well as the means of collection is housed in a common enclosure communicating with the fan and provided with an inlet opening and an outlet opening for the product to be cooled, these two openings being centered on the longitudinal axis of said tubular elements, the tank and / or the capture means which may themselves constitute parts of said common enclosure. „.--”