GB2238008A

GB2238008A - Cooling rolled sections

Info

Publication number: GB2238008A
Application number: GB9020444A
Authority: GB
Inventors: Walter Worgt; Norbert Brennecke; Ulf Hoeltge
Original assignee: Schwermaschinenbau Kombinat Ernst Thalmann VEB; SKET Schwermaschinenbau Magdeburg GmbH
Current assignee: Schwermaschinenbau Kombinat Ernst Thalmann VEB; SKET Schwermaschinenbau Magdeburg GmbH
Priority date: 1989-11-16
Filing date: 1990-09-19
Publication date: 1991-05-22
Anticipated expiration: 2010-09-19
Also published as: RU1831391C; UA11087A1; DD288990A5; IT9047898A0; DE4009707A1; GB2238008B; IT1240099B; IT9047898A1; GB9020444D0

Abstract

Apparatus for cooling rolled sections comprises a housing having wear strips 16 for supporting the section, and a plurality of longitudinally-extending coolant tubes 9 having nozzles 10 disposed around the path of travel of the section and to which coolant is supplied. The tubes 9 are rotatably adjustable to an optimum coolant impingement angle for the particular section without needing to change components of the apparatus. <IMAGE>

Description

ARRANGEMENT FOR PARTIAL COOLING FOR THERMAL ADJUSTMENT OF SPECIAL ROLLED SECTIONS The invention relates to an arrangement for partial cooling for thermal adjustment of special rolled sections after the rolling process.

In small-section-steel and wire rolling mills, cooling sections are used during or immediately after the rolling process for the purposes of influencing temperature and structure formation or for the purposes of reducing scale. When the rolled material passes through these cooling sections, pressurised water is preferably applied thereto and therefore gives the desired effect of a reduction in temperature which is controlled in respect of time.

The particularities in that respect and also the results achieved are generally known. The rolled material may be round material with a smooth or ribbed surface, quadrangular material, hexagonal material, flat material, that is to say rolled material with a doubly symmetrical profile cross-section, etc.

The disadvantage of those apparatuses is that due to the use of cooling tubes of round internal cross-section, it is only possible to cool special sections of small dimensions, and the level of cooling intensity cannot be adapted and matched to specific parts of the profile crosssection.

In order to provide a cooling effect with simultaneous thermal adjustment in relation to singly symmetrical sections such as angular, Ushaped, T-shaped and double-T-shaped sections, an apparatus was developed in accordance with DD-WP 266750. That apparatus is of such a construction as to be longitudinally dividable, with the upper portions and lower portions having separate water and air connections and the internal contours being adapted to the configuration of the respective rolled material.

The disadvantage of that arrangement is that the parts provided in the tube have to be changed for each rolled section to be cooled. Another disadvantage is that it is not possible to provide for separate cooling of specific cross-sectional portions.

In order to permit the separate cooling of specific portions of the cross-section of the rolled material, an arrangement was developed in accordance with DE 30 43 117, wherein the cooling tubes are of a crosssection which differs from a circular cross-section and which is adapted to the cross-section of the rolled material. In addition the level of intensity of the cooling effect, which corresponds to the individual portions of the cross-section of the rolled material, is achieved by flow deflector or baffle members and the high level of turbulence which is required for that purpose is attained by means of turbulence-enhancing means.

The disadvantage of that arrangement is that adaptor portions are required in order to adapt the cooling cross-section to the respective cross-section of the rolled material, and that requires additional stoppage times when changing the rolling programme.

Another arrangement (DE 12 74 151) comprises a carrier plate which is arranged at the discharge end transversely with respect to the direction of movement of the sections through the arrangement and which is provided with an opening adapted to the shape of the section, the arrangement further comprising tubular sprinkler bodies on both sides of the opening, with discharge openings which are directed towards the section and which are arranged and are adjustable in such a way that the effective length of their slots or rows of openings extends approximately over the side length of the regions of the section, which differ in regard to their wall thickness or gauge. The disadvantage of that apparatus is that the shape and the arrangement of the sprinkler bodies also has to be adapted to the shape of the rolled material and thus universal use is not possible.

An aim of the invention is to provide an arrangement which permits partial cooling for thermal adjustment of rolled material of particular cross-sectional shape, that is to say, special sections. The term special sections is used in this connection to denote rolled sections of nonsymmetrical cross-section and with differing distribution of mass. In this respect reduction in the formation of scale and control and influencing of the structure are not primary considerations.

A more specific aim is to provide an arrangement which permits effective partial cooling for thermal adjustment of rolled asymmetrical special sections. In this connection it is highly desirable that the arrangement should be universally suitable for a large number of different special sections so that long conversion times for changing specific components are avoided.

According to one aspect, the invention provides an arrangement for partial cooling for thermal adjustment of special rolled sections of asymmetrical cross-sectional shapes, comprising a housing providing a passage through which the rolled section passes, the housing having a plurality of longitudinally extending rotatably adjustable jetting tubes which are disposed around the path of the section and to which cooling water may be supplied, the jetting tubes having jetting nozzles disposed along their length.

According to another aspect, the invention provides an arrangement for partial cooling for thermal adjustment of special rolled sections of asymmetrical cross-sectional shapes, the arrangement being disposable within a mill train both between the roll stands and also downstream of the last roll stand at one location or a plurality of locations in succession wherein, disposed within the space which is enclosed by two interconnected housing portions, a lower housing portion and an upper housing portion, is a rolled section guide passage with discharge flow openings and arranged around the passage are a plurality of rotatably adjustable jetting tubes which are secured to the lower housing portion and the upper housing portion respectively and which are fed from water boxes secured to the intake end of the arrangement, the jetting tubes each having a plurality of successively arranged jetting nozzles secured to the respective jetting tube.

Preferably the maximum adjustment angle of the jetting tubes is equal to 5 ... 100. The number of jetting nozzles is advantageously from 20 to 40, depending on the respective jetting tube. Preferably the jetting tubes are arranged symmetrically, with the majority of the nozzles being arranged beneath and above the rolled material guide passage. The number of jetting tubes is preferably 4... 10.

Desirably there is arranged at the water discharge end of the jetting nozzles a respective rotatable ball with a central bore which is conically enlarged at one end. In that way the jet of water issuing therefrom can be additionally directed, but complete closure of the jetting nozzle is also possible by virtue of a rotary movement through 900.

It is also desirable that disposed between the discharge flow openings of the rolled material guide passage at the sides of the rolled material guide passage and in its lower region are interchangeable wear strips or bars.

A water stripping arrangement is normally arranged at the discharge end of the cooling box. Preferably the arrangement is provided with an intake funnel member at the upstream end and a stripping nozzle at the downstream end and with a plurality of supports for supporting it at the underside.

The invention will now be described in greater detail by way of example with reference to the drawings in which: Figure 1 is a side view of an embodiment of a cooling arrangement according to the invention, Figure 2 is a view in longitudinal section through the cooling arrangement, Figure 3 is a view in section taken along line B-B in Figure 2, Figure 4 is the view indicated at A in Figure 1, Figure 5 is a view in section through the special valve, and Figure 6 shows detail of a jetting nozzle.

The cooling arrangement comprises a lower housing portion 7 and an upper housing portion 8 which are fixedly connected together by the keys 17. A water box or tank 5 is flanged to the lower housing portion 7 at the front as viewed in the direction of rolling, and a water box or tank 6 is flanged to the upper housing portion 8. The intake funnel member 2 is arranged between the upper water box 6 and the lower water box 5 on which the water connection 4 is disposed. Welded into the housing of the upper water box 6 and the lower water box 5 is a tube 21 in which the rotatable, screw-threadedly mounted special valve member 20 is arranged and which has ports 12 through which water may enter, the valve being operable by rotary member 20 so that an annular seal ring carried thereby moves away from a valve seat as shown in ghost lines in Figure 5.Jetting tubes 9 are screwed into the tube 21 and fixed in position by means of rotational securing means 14. The oppositely disposed end of the jetting tubes 9 is fixed in the lower housing portion 7 and in the upper housing portion 8 respectively by means of a clamping device 11. The jetting nozzles 10 are screwed into the jetting tubes 9.

Disposed in the interior of the cooling arrangement are wear strips or bars 16 with discharge flow openings 15 arranged therebetween. Provided at the rear or downstream portion of the cooling arrangement is an air stripping nozzle 3 with an air connection 18 and air bores 19. The entire cooling arrangement is fixed on a foundation structure by means of supports 22. The jetting nozzle 10 which is screwed into the attachment portion 23 of the jetting tube 9 comprises a screw means 24 in which there is disposed a rotatable non-corroding ball 13 which has a central bore which is conical at the inner end (see Figure 6).

The mode of operation of the arrangement will now be described in greater detail: The cooling water at a pressure of preferably from 0.2 to 0.8 MPa passes through the water connection 4 into the lower water box 5 and from there into the upper water box 6. From the water boxes 5 and 6 the cooling water flows through the bores 12 into the special valves 20 and from there through the jetting tubes 9 and the jetting nozzles 10 on to the rolled material, where the discharge of the cooling water takes place from bores of a diameter d in the balls 13, that is to say preferably in the form of a round jet.After release of the clamping device 11 and a rotational securing means 14, the jetting tubes 9 can be rotated through the angle c(, and in that way the jet of water can be directed in the optimum fashion on to the rolled material 1 which moves through the cooling arrangement from left to right in Figure 2. In order to avoid an accumulation of water in the lower housing portion 7 and in the upper housing portion 8, the assembly has sufficient discharge flow openings 15 which are disposed between the replaceable wear strips or bars 16.

Preferably keys 17 are used for assembly of the cooling arrangement and in particular for rapid removal of the upper portions, in the event of a fault or disturbance. In order to strip off the water which is entrained by the rolled material, compressed air passes through the air bores 19 of the stripping nozzle 3 on all sides and in opposite relationship to the direction of rolling movement, on to the rolled material 1, at an angle ss (see Figure 2).

Claims

1. An arrangement for partial cooling for thermal adjustment of special rolled sections of asymmetrical cross-sectional shapes, comprising a housing providing a passage through which the rolled section passes, the housing having a plurality of longitudinally extending rotatably adjustable jetting tubes which are disposed around the path of the section and to which cooling water may be supplied, the jetting tubes having jetting nozzles disposed along their length.

2. An arrangement for partial cooling for thermal adjustment of special rolled sections of asymmetrical cross-sectional shapes, the arrangement being disposable within a mill train both between the roll stands and also downstream of the last roll stand at one location or a plurality of locations in succession wherein, disposed within the space which is enclosed by two interconnected housing portions, a lower housing portion and an upper housing portion, is a rolled section guide passage with discharge flow openings and arranged around the passage are a plurality of rotatably adjustable jetting tubes which are secured to the lower housing portion and the upper housing portion respectively and which are fed from water boxes secured to the intake end of the arrangement, the jetting tubes each having a plurality of successively arranged jetting nozzles secured to the respective jetting tube.

3. An arrangement according to claim 2, which is provided with a stripping nozzle at the downstream end.

4. An arrangement according to claim 2, which is provided with an intake funnel member at the upstream end and a stripping nozzle at the downstream end and with a plurality of supports for supporting it at the underside.

5. An arrangement according to any preceding claim, wherein the maximum adjustment angle of the jetting tubes is equal to 5 ... 100.

6. An arrangement according to any preceding claim, wherein arranged at the water discharge side of the jetting nozzles is a respective rotatable ball with a central bore which is conically enlarged at one end.

7. An arrangement according to any preceding claim, wherein the arrangement of the jetting tubes, and therewith the jetting nozzles, is symmetrical, wherein the majority of the jetting nozzles is disposed beneath and above the rolled section and wherein the number of jetting tubes is from 4 to 10.

8. An arrangement according to any preceding claim, wherein disposed between discharge flow openings of the rolled section passage at the sides of the rolled section passage and in its lower region, are replaceable wear strips.

9. An arrangement for partial cooling for thermal adjustment of special rolled sections of asymmetrical cross-sectional shapes substantially as hereinbefore described with reference to the accompanying drawings.