KR20000039755A - Lower cooler for cooling hot rolling plate with water - Google Patents

Lower cooler for cooling hot rolling plate with water Download PDF

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Publication number
KR20000039755A
KR20000039755A KR1019980055177A KR19980055177A KR20000039755A KR 20000039755 A KR20000039755 A KR 20000039755A KR 1019980055177 A KR1019980055177 A KR 1019980055177A KR 19980055177 A KR19980055177 A KR 19980055177A KR 20000039755 A KR20000039755 A KR 20000039755A
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KR
South Korea
Prior art keywords
cooling
water
strip
injection nozzles
nozzles
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KR1019980055177A
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Korean (ko)
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KR100373680B1 (en
Inventor
민경준
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이구택
포항종합제철 주식회사
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Priority to KR10-1998-0055177A priority Critical patent/KR100373680B1/en
Publication of KR20000039755A publication Critical patent/KR20000039755A/en
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Publication of KR100373680B1 publication Critical patent/KR100373680B1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
    • B21B45/0203—Cooling
    • B21B45/0209—Cooling devices, e.g. using gaseous coolants
    • B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
    • B21B45/0218—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for strips, sheets, or plates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B1/00—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means
    • B05B1/14—Nozzles, spray heads or other outlets, with or without auxiliary devices such as valves, heating means with multiple outlet openings; with strainers in or outside the outlet opening
    • B05B1/20—Arrangements of several outlets along elongated bodies, e.g. perforated pipes or troughs, e.g. spray booms; Outlet elements therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B33/00—Safety devices not otherwise provided for; Breaker blocks; Devices for freeing jammed rolls for handling cobbles; Overload safety devices
    • B21B33/02—Preventing fracture of rolls

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)

Abstract

PURPOSE: A lower cooler is provided to maximize cooling efficiency under the same water pressure for regularly cooling the upper and the lower face of a hot rolling plate. CONSTITUTION: A lower cooler contains a water supplier(1), many spraying nozzles(31) and a header body(5). The spraying nozzles are arranged in a line, having a certain interval along the central line of the outer face of the header body. Also, the spraying nozzle sprays the cooling water in a cone. A strip area between central lines of a table roller(4) and an area contacted with cooling water particles from the spraying nozzles are in the ratio of less than 0.3.

Description

열연판수냉을 위한 하부수냉장치Bottom water cooling device for hot rolled sheet water cooling

이 발명은 금속판을 열간압연한 후에 열연판을 수냉시키는 열연판수냉장치에 관한 것이며, 특히, 동일한 수압하에서 최대의 냉각효율을 발휘함으로써 상부수냉장치와 동일한 냉각속도를 얻을 수 있는 하부수냉장치에 관한 것이다.The present invention relates to a hot rolled sheet water cooling device for cooling a hot rolled plate after hot rolling of a metal plate, and more particularly, to a lower water cooling device capable of obtaining the same cooling rate as an upper water cooling device by exhibiting maximum cooling efficiency under the same water pressure. will be.

일반적으로 열간사상압연후 스트립(S)은, 도 1에 보이듯이, 런아웃테이블(RUN OUT TABLE)을 주행하면서 스트립의 상하면에 분사되는 냉각수(W)에 의해 냉각된다. 여기에서는 스트립(S)의 상면을 냉각시키기 위한 냉각수를 분사하는 노즐장치를 상부냉각장치라고 하고, 스트립(S)의 하면을 냉각시키기 위한 냉각수를 분사하는 노즐장치를 하부냉각장치라고 부르기로 한다. 상부냉각장치와 하부냉각장치 모두 급수관(1)과 연결된 대형의 냉각수관(2)으로부터 분기된 다수의 소형파이프로 연결된 라미너노즐(3)이 사용되어 왔다. 이러한 라미너노즐(3)은 냉각수를 발산각이 거의 없는 수류의 형태로 분사한다.In general, after hot rolling, the strip S is cooled by the coolant W sprayed on the upper and lower surfaces of the strip while driving the RUN OUT TABLE, as shown in FIG. 1. Here, the nozzle device for injecting the cooling water for cooling the upper surface of the strip S is called an upper cooling device, and the nozzle device for injecting the cooling water for cooling the lower surface of the strip S is called a lower cooling device. Both the upper cooling unit and the lower cooling unit have been used laminator nozzles 3 connected by a plurality of small pipes branched from a large cooling water pipe 2 connected to the water supply pipe 1. The laminator nozzle 3 sprays the coolant in the form of a stream of water with almost no divergence angle.

이러한 종래의 냉각장치를 이용하는 경우에는, 스트립(S)의 상면은 스트립위에 체류하는 냉각수에 의해 스트립의 하면보다 냉각효과가 커서 상하면의 냉각속도가 상이하다. 그로 인하여, 스트립의 상면과 하면에 온도차이가 야기되어 스트립의 내부조직이 달라지고 스트립내부에 잔류응력이 발생하게 되어 냉각후에 스트립의 평탄도를 악화시키는 등과 같이 제품의 품질을 저하시키는 문제점이 지적되고 있다.In the case of using such a conventional cooling device, the upper surface of the strip S has a greater cooling effect than the lower surface of the strip due to the coolant remaining on the strip, and thus the cooling rate of the upper and lower surfaces is different. As a result, there is a problem that the quality of the product is degraded, such as a temperature difference between the upper and lower surfaces of the strip, resulting in a change in the internal structure of the strip and a residual stress in the strip, which deteriorates the flatness of the strip after cooling. It is becoming.

실측의 결과에 의하면 스트립 상하면에 각각 동일한 수량의 냉각수를 분사할 때의 상부냉각능력과 하부냉각능력의 사이에는 약 1:0.49의 관계가 있다.According to the measurement results, there is a relationship of about 1: 0.49 between the upper cooling capacity and the lower cooling capacity when spraying the same amount of cooling water on the upper and lower strips.

그러므로, 상하부에서 균일한 냉각효과를 얻기 위해서는 하부냉각수량이 상부냉각수량의 약 2배이어야 한다. 그러나, 스트립은 다수의 병렬로 배열된 테이블롤러(4)에 의해 이송되며, 인접한 테이블롤러(4) 사이의 공간이 협소하여 냉각장치를 증설하기도 곤란하다.Therefore, in order to obtain a uniform cooling effect in the upper and lower parts, the amount of lower cooling water should be about twice the amount of upper cooling water. However, the strip is conveyed by a plurality of table rollers 4 arranged in parallel, and the space between adjacent table rollers 4 is narrow, making it difficult to add a cooling device.

이 발명은 위에서 설명한 문제점을 해결하기 위한 것으로서, 열연사상압연후에 스트립을 냉각시킬 때, 상하면의 온도차이를 발생시킴이 없이 폭방향으로 균일한 냉각을 실시할 수 있는 하부수냉각장치를 제공하기 위한 것이다.SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and when providing a lower water cooling device capable of performing uniform cooling in the width direction without causing a temperature difference between the upper and lower surfaces when cooling the strip after hot rolling, will be.

도 1 - 종래의 스트립냉각을 위한 수냉장치를 도시한 사시도1-a perspective view of a conventional water cooling apparatus for strip cooling

도 2 - 이 발명의 한 실시예에 따른 하부수냉장치의 부분사시도2-partial perspective view of a lower water cooling apparatus according to an embodiment of the present invention;

도 3 - 도 2에 도시된 하부수냉장치에서의 분사노즐의 배치관계를 설명하기 위한 스트립수냉구간의 평면도3 to 2 are plan views of strip water cooling sections for explaining the arrangement of the spray nozzles in the lower water cooling device shown in FIGS.

위와 같은 기술적 과제를 해결하기 위한 이 발명에 따른 하부수냉장치는 냉각수를 공급하는 급수관과, 냉각수를 스트립의 하면을 향해 분사하는 다수의 분사노즐 및, 공급된 냉각수를 모든 분사노즐에 동일한 압력으로 분배하는 헤더본체를 포함한다. 분사노즐은 헤더본체의 외면의 중앙선을 따라 소정의 간격으로 일렬로 배열되어 있으며, 분사노즐은 냉각수를 원뿔형으로 분사하는 노즐이다. 스트립을 이송하는 테이블롤러의 중심선과 중심선 사이의 스트립의 면적과 원뿔형으로 분사되는 냉각수 입자가 스트립에 접촉하는 면적의 비율은 0.3 미만이다. 인접한 분사노즐 사이의 피치와 분사노즐에서 분사되는 냉각수 입자가 스트립에 접촉하는 원의 직경은 아래의 수학식과 같은 관계를 갖는다.The lower water cooling device according to the present invention for solving the above technical problem is a water supply pipe for supplying the cooling water, a plurality of injection nozzles for spraying the cooling water toward the lower surface of the strip, and distributes the supplied cooling water to all the injection nozzles at the same pressure It includes the header body. The spray nozzles are arranged in a row at predetermined intervals along the center line of the outer surface of the header body, and the spray nozzles are nozzles for spraying cooling water in a conical shape. The ratio of the area of the strip between the centerline and the centerline of the table roller conveying the strip and the area where the coolant particles sprayed in the cone contact the strip is less than 0.3. The pitch between adjacent spray nozzles and the diameter of the circle where the coolant particles sprayed from the spray nozzles contact the strip have the following equation.

또한, 짝수열의 분사노즐의 위치를 홀수열의 분사노즐의 위치로부터 절반피치만큼 피치방향으로 이동시키는 것이 양호하다.In addition, it is preferable to shift the position of even-numbered injection nozzles in the pitch direction by half a pitch from the position of the even-numbered injection nozzles.

이 발명의 상기 및 기타의 특성과 장점은 아래의 양호한 실시예에 대한 설명에 의해 좀더 명료해질 것이다.These and other features and advantages of this invention will become more apparent from the following description of the preferred embodiments.

[발명의 양호한 실시예에 대한 설명][Description of Preferred Embodiment of the Invention]

이하, 첨부된 도면을 참조하여 이 발명에 따른 하부수냉장치의 양호한 실시예에 대해 상세히 설명한다.Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the lower water cooling apparatus according to the present invention.

이 실시예에 따른 하부수냉장치는 도 2에 도시된 바와 같이 일측에 덮개(22)가 조여진 플랜지부(21)가 형성된 헤더본체(5)와, 상기 헤더본체(5)의 외면의 중앙선을 따라 소정의 간격으로 일렬로 배열되어 냉각수를 원뿔형으로 분사하는 분사노즐(31) 및, 헤더본체(5)의 중심하면에 용접되어 냉각수관(2)에 냉각수를 공급하는 급수관(1)으로 구성된다.As shown in FIG. 2, the lower water cooling apparatus according to the present embodiment has a header body 5 having a flange portion 21 having a cover 22 tightened on one side thereof, and a center line of an outer surface of the header body 5. An injection nozzle 31 which is arranged in a line at predetermined intervals and sprays the cooling water in a conical shape, and a water supply pipe 1 which is welded to the central surface of the header body 5 and supplies the cooling water to the cooling water pipe 2.

분사노즐(31)은 테이블롤러(4) 사이의 제한된 공간내에서 스트립의 냉각능을 최대로 확보하기 위하여 원뿔형으로 냉각수(W)를 분사한다.The spray nozzle 31 sprays the cooling water W in a conical shape in order to maximize the cooling capacity of the strip within the limited space between the table rollers 4.

한편, 분사노즐(31)의 배치시에는 냉각효율은 물론이고 냉각수량의 폭방향의 균일한 분포 및 테이블롤러(4) 사이로의 배수성을 감안하여야 한다. 아래에서는 도 3을 보면서 이 실시예에 따른 분사노즐(31)의 배치를 설명하겠다.On the other hand, when arranging the injection nozzles 31, it is necessary to take into account not only the cooling efficiency but also the uniform distribution in the width direction of the cooling water amount and the drainage between the table rollers 4. Hereinafter, the arrangement of the injection nozzle 31 according to this embodiment will be described with reference to FIG. 3.

테이블롤러(4)의 중심선(41)과 중심선(41) 사이의 스트립(S)의 면적(Ar)과 원뿔형으로 분사되는 냉각수 입자가 스트립(S)에 접촉하는 면적(An)의 관계는 냉각수의 배수성을 고려하여 아래의 수학식 1과 같이 제한한다.The relationship between the area Ar of the strip S between the center line 41 and the center line 41 of the table roller 4 and the area An in which the coolant particles sprayed in a conical shape contact the strip S are determined by the cooling water. In consideration of the multiples, it is limited as in Equation 1 below.

수학식 1의 비율이 0.3을 초과하면, 테이블롤러(4)를 타고넘어가는 냉각수량이 많아지면서 배수성을 떨어뜨리고, 다음 열의 분사노즐(31)에서 분사된 냉각수가 스트립(S)의 표면에 직접 접촉하는 것을 방해하여 냉각효율에도 악영향을 미친다.When the ratio of Equation 1 exceeds 0.3, the amount of cooling water passing through the table roller 4 increases and the drainage is reduced, and the cooling water injected from the next row of injection nozzles 31 is directly applied to the surface of the strip S. Interfering with contact adversely affects cooling efficiency.

한편, 헤더본체(5)의 상면에 폭방향으로 균일하게 배치된 분사노즐(31)의 피치(P)는 폭방향의 균일한 수량분포를 얻기 위하여 아래의 수학식 2와 같이 제한한다.On the other hand, the pitch P of the injection nozzle 31 uniformly arranged in the width direction on the upper surface of the header body 5 is limited as shown in Equation 2 below to obtain a uniform water distribution in the width direction.

여기에서, D는 분사노즐(31)에서 분사되는 냉각수 입자가 스트립(S)에 접촉하는 원의 직경이다.Here, D is the diameter of the circle in which the coolant particles injected from the spray nozzle 31 contact the strip S. FIG.

P/D값이 0.125 미만이면, 인접한 분사노즐(31)에서 분사되는 냉각수들이 상호간섭을 일으켜 냉각효율을 저하시키며, P/D값이 0.75를 초과하면, 폭방향의 수량분포가 불균일해져서 폭방향의 냉각편차를 야기시킨다.If the P / D value is less than 0.125, the cooling water injected from the adjacent injection nozzles 31 may interfere with each other to reduce the cooling efficiency. If the P / D value exceeds 0.75, the water distribution in the width direction becomes uneven and the width direction Cause cooling deviations.

또한, 폭방향의 유량편차를 줄이기 위한 부가적인 방안으로, 도 3에 도시된바와 같이, 짝수열의 분사노즐(31)의 위치를 홀수열의 분사노즐(31)의 위치로부터 절반피치(P/2)만큼 피치방향으로 이동시킨다.In addition, as an additional method for reducing the flow rate deviation in the width direction, as shown in FIG. 3, the position of the even-numbered injection nozzles 31 is half the pitch (P / 2) from the position of the odd-numbered injection nozzles 31. The pitch direction.

위와 같이 구성된 하부수냉장치를 이용한 냉각에서는 파이프라미너노즐(3)을 일정하게 배열시킨 종래의 하면수냉장치에 비해, 동일한 수압하에서 약 2배의 냉각속도를 나타낸다. 그러므로, 이 실시예의 하부냉각장치를 종래의 상부냉각장치와 함께 사용하면, 상하의 온도차이가 없이 냉각을 수행할 수 있다.In the cooling using the lower water cooling device configured as described above, the cooling speed is about twice as high as that of the conventional lower surface water cooling device in which the pipe laminator nozzles 3 are constantly arranged. Therefore, when the lower cooling device of this embodiment is used together with the conventional upper cooling device, cooling can be performed without a temperature difference of up and down.

위에서 양호한 실시예에 근거하여 이 발명을 설명하였지만, 이러한 실시예는 이 발명을 제한하려는 것이 아니라 예시하려는 것이다. 이 발명이 속하는 분야의 숙련자에게는 이 발명의 기술사상을 벗어남이 없이 위 실시예에 대한 다양한 변화나 변경 또는 조절이 가능함이 자명할 것이다. 그러므로, 이 발명의 보호범위는 첨부된 청구범위에 의해서만 한정될 것이며, 위와 같은 변화예나 변경예 또는 조절예를 모두 포함하는 것으로 해석되어야 할 것이다.While the invention has been described above based on the preferred embodiments thereof, these embodiments are intended to illustrate rather than limit the invention. It will be apparent to those skilled in the art that various changes, modifications, or adjustments to the above embodiments can be made without departing from the spirit of the invention. Therefore, the protection scope of the present invention will be limited only by the appended claims, and should be construed as including all such changes, modifications or adjustments.

위에서 설명한 바와 같이 이 발명에 따르면, 사이드가이드와의 과도한 충돌로 인하여 스트립의 선단부 또는 미단부가 꼬이거나 접히는 것을 방지함으로써 압연롤이 손상되는 것을 방지할 수 있다.As described above, according to the present invention, it is possible to prevent the rolling roll from being damaged by preventing the tip or tail end of the strip from being twisted or folded due to excessive collision with the side guide.

Claims (2)

열간압연후에 열연판의 하면을 수냉시키는 하부수냉장치에 있어서,In the lower water cooling device for cooling the lower surface of the hot rolled sheet after hot rolling, 냉각수를 공급하는 급수관과, 냉각수를 스트립의 하면을 향해 분사하는 다수의 분사노즐 및, 공급된 냉각수를 모든 분사노즐에 동일한 압력으로 분배하는 헤더본체를 포함하고,A water supply pipe for supplying the cooling water, a plurality of injection nozzles for injecting the cooling water toward the lower surface of the strip, and a header body for distributing the supplied cooling water to all the injection nozzles at the same pressure, 분사노즐은 헤더본체의 외면의 중앙선을 따라 소정의 간격으로 일렬로 배열되어 있으며,Injection nozzles are arranged in a line at predetermined intervals along the center line of the outer surface of the header body, 분사노즐은 냉각수를 원뿔형으로 분사하는 노즐이고,Injection nozzle is a nozzle for spraying coolant in a conical shape, 스트립을 이송하는 테이블롤러의 중심선과 중심선 사이의 스트립의 면적과 원뿔형으로 분사되는 냉각수 입자가 스트립에 접촉하는 면적의 비율은 0.3 미만이며,The ratio of the area of the strip between the centerline and the centerline of the table roller conveying the strip and the area of the condensed coolant particles contacting the strip is less than 0.3, 인접한 분사노즐 사이의 피치와 분사노즐에서 분사되는 냉각수 입자가 스트립에 접촉하는 원의 직경은 아래의 수학식과 같은 관계를 갖는 것을 특징으로 하는 하부수냉장치.A pitch between adjacent spray nozzles and a diameter of a circle in which the coolant particles sprayed from the spray nozzles contact the strip have a relationship as in the following equation. 제 1 항에 있어서,The method of claim 1, 짝수열의 분사노즐의 위치를 홀수열의 분사노즐의 위치로부터 절반피치만큼 피치방향으로 이동시킨 것을 특징으로 하는 하부수냉장치.A lower water cooling device, characterized in that the position of even-numbered injection nozzles is moved in the pitch direction by half a pitch from the position of the even-numbered injection nozzles.
KR10-1998-0055177A 1998-12-15 1998-12-15 Lower Water Cooling System for Hot Rolled Plate Cooling_ KR100373680B1 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20040088298A (en) * 2003-04-09 2004-10-16 주식회사 포스코 Strip floating device in apron of table roller
KR100843843B1 (en) * 2006-12-21 2008-07-03 주식회사 포스코 Thick Plate Cooling Apparatus
KR101399877B1 (en) * 2012-08-30 2014-05-27 현대제철 주식회사 Cooler for rolling mill

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101326031B1 (en) 2013-06-18 2013-11-07 한국기계연구원 Nozzle module for forming swirl

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20040088298A (en) * 2003-04-09 2004-10-16 주식회사 포스코 Strip floating device in apron of table roller
KR100843843B1 (en) * 2006-12-21 2008-07-03 주식회사 포스코 Thick Plate Cooling Apparatus
KR101399877B1 (en) * 2012-08-30 2014-05-27 현대제철 주식회사 Cooler for rolling mill

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