JP2002326004A - Cleaning solution, and method and apparatus for cleaning rolling oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently remove scum and other foreign matters mixed into a cleaning solution in a cleaning solution circulating path provided for a strip cleaning apparatus. SOLUTION: A scum suction device 4 is installed in a cleaning solution tank 2 provided at a cleaning solution circulating path 3 of a strip cleaning apparatus 1, and a cleaning solution mainly containing scum sucked in by the scum suction device 4 is supplied to a scum separation device 7 so as to fill the scum separation device 7. Thereafter, the scum is allowed to float and is scraped out by a scraper, and foreign matters such as an iron powder is precipitated, deposited and discharged from the lower end part of the scum separation device 7. Meanwhile, the treatment of the cleaning solution is continuously carried out by filling a scum separation device 6 with the cleaning solution mainly containing the scum using the scum suction device 4 and allowing the scum to float and at the same time, precipitating and depositing the foreign matters such as the iron powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing foreign matter such as scum and iron powder mixed in a rolling oil or a cleaning liquid used in a cold rolling mill or a strip cleaning apparatus in a circulation path of the rolling oil or the cleaning liquid. And an apparatus.

[0002]

2. Description of the Related Art In order to prevent the occurrence of heat scratches or the like due to frictional heat with a rolling roll, a strip being cold-rolled is subjected to rolling of an emulsion obtained by mixing water and oil, or a neat made only of oil. Oil is supplied, and foreign matters such as scum and iron powder generated during rolling are mixed in the supplied rolling oil. Since the rolling oil is used circulatingly, if these foreign substances are caught between the strip and the rolling roll, the strip will have surface flaws and poor gloss.

[0003] Also, strips that have been cold rolled and annealed and pickled have fine dirt and foreign matter adhered to the surface, and if they are temper rolled as they are, surface flaws or poor gloss will occur on the strips. Before cleaning, wash with an alkaline cleaning solution or the like.
The cleaning liquid used for cleaning is discarded because foreign substances such as scum are mixed therein. However, it is uneconomical and it is desirable to use the cleaning liquid in circulation.

[0004] In order to prevent surface defects and poor gloss of the strip in cold rolling and to circulate and use the cleaning liquid used for cleaning the strip, foreign substances such as scum and iron powder in the rolling oil and the cleaning liquid are removed. Although it is necessary to remove it, in this case, since the rolling oil and the cleaning liquid need to be continuously supplied in a large amount, it is necessary to perform the removal efficiently.

Conventionally, as a method for removing foreign matter in rolling oil, for example, according to Japanese Patent Application Laid-Open No. Hei 8-24933, rolling is temporarily stopped and rolling oil is supplied little by little to a scum separating tank. A device is known in which a scum floating on a rolling oil level overflows by raising a rolling oil level in the inside at a slow speed.
According to Japanese Patent No. 7329, there is known a device for sucking scum by a scum suction pipe in which a scum suction port is positioned at a liquid level by a float.

[0006]

However, in the apparatus disclosed in Japanese Patent Application Laid-Open No. H8-24933, the liquid level of the scum separation tank is slowly increased to allow the scum to overflow with a good yield. Has to be temporarily stopped.
In the apparatus disclosed in Japanese Patent Application Laid-Open No. 9-209, the rolling oil flows into the receiving pits, causing undulations, and the scums are not sufficiently floated and separated due to the undulations. There is a problem that yield is poor.

The present invention is intended to efficiently remove foreign substances such as scum and iron powder mixed in rolling oil and cleaning liquid used in a cold rolling mill and a strip cleaning apparatus. By suctioning and supplying to the scum separation tank, the separation efficiency in the scum separation tank is improved,
(2) In the scum separation tank, the liquid level rise is performed gently to prevent turbidity of scum and iron powder due to rolling and agitation of the rolling oil and cleaning liquid. (3) By providing a plurality of scum separation tanks, It is an object of the present invention to secure a sufficient time for ascent of iron and settling of iron powder.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the gist thereof is as follows. (1) The cleaning liquid of the strip cleaning device is stored in the cleaning liquid tank, the scum floating in the cleaning liquid tank is sucked and stored in a plurality of scum separation tanks, and the scum floating in the scum separation tank is scraped out and the upper end of the tank Discharged from
A method of cleaning a cleaning liquid, wherein an operation of discharging foreign substances settling in the scum separation tank from the lower end of the tank is alternately performed for each tank.

(2) A cleaning liquid tank is provided in a cleaning liquid circulation path of the strip cleaning apparatus, a scum suction device is provided in the cleaning liquid tank, and a cleaning liquid detour is provided by the scum suction device to exit the cleaning liquid tank and return to the cleaning liquid tank. A plurality of scum separation tanks provided in the washing liquid bypass, the scum suction device includes a scum receiver having a scum inflow portion on a scum receiving inlet side, a suction pump for sucking scum in the scum receiver, and a liquid surface. A lifting drive mechanism for raising and lowering the scum receiver in response to a signal from a level meter is provided.The scum separation tank includes a scum receiving port that communicates with the suction pump, and a discharge port of a cleaning fluid that communicates with the cleaning fluid tank. A liquid level pressurizing chamber that raises the liquid level, a scraper that slides outside the liquid level pressurizing chamber, and a foreign substance discharge port that discharges accumulated foreign substances. Cleaning apparatus of the cleaning liquid, characterized and.

(3) Rolling oil from a cold rolling mill is stored in a rolling oil tank, scum floating in the rolling oil tank is sucked and stored in a plurality of scum separation tanks, and floating in the scum separation tank. A method of cleaning rolling oil, wherein the operation of scraping out scum to be discharged from the upper end of the tank and discharging foreign substances settling in the scum separation tank from the lower end of the tank is alternately performed for each tank.

(4) A first dirty tank, a rolling oil tank, and a second dirty tank are sequentially provided in the rolling oil circulation path of the cold rolling mill from the upstream side, and a scum suction device is provided in the rolling oil tank. A rolling oil detour is provided by the suction device to exit the rolling oil tank and return to the rolling oil tank, a plurality of scum separation tanks are provided in the rolling oil detour, and scum flows into the scum suction device into the scum receiving inlet side. A scum receiver having a portion, a suction pump for sucking scum in the scum receiver, and a lifting drive mechanism for raising and lowering the scum receiver in response to a signal from a liquid level meter. A scum receiving port communicating with the pump, a cleaning liquid outlet communicating with the rolling oil tank, a liquid level pressurizing chamber for raising the liquid level, and a scraper sliding outside the liquid level pressurizing chamber. If, rolling oil cleaning apparatus characterized in that a foreign matter discharge port for discharging the deposited foreign matter.

(5) In the cleaning liquid purifying apparatus of (2) or the rolling oil purifying apparatus of (4), a closed space is formed in the liquid level pressurizing chamber on the liquid level. Purification of cleaning liquid and rolling oil, characterized in that a wall having a scum inlet formed below and a pressure gas supply port provided in the wall and having an opening adjusted by a signal of a liquid level meter are provided. apparatus.

[0013]

FIG. 1 shows an embodiment in which a cleaning liquid purifying apparatus according to the present invention is applied to a strip cleaning apparatus. In FIG. 1, a strip cleaning apparatus 1
The cleaning solution circulation path 3 is provided in which the alkaline solution supplied to the strip cleaning device exits the strip cleaning device 1 and returns to the strip cleaning device 1 via the cleaning solution tank 2.

The washing liquid tank 2 is provided with a scum suction device 4 for sucking scum floating in the tank.
A cleaning liquid bypass path 5 is provided in which the cleaning liquid mainly composed of scum leaves the cleaning liquid tank 2 and returns to the cleaning liquid tank 2 by the scum suction device 4. The scum separation tanks 6 and 7 are provided in the cleaning liquid bypass path 5, and foreign matters such as scum and iron powder separated by the scum separation tanks 6 and 7 are sent to the waste liquid tank 8 and the waste liquid pit 9.

FIG. 2 is a perspective view of the scum suction device 4 provided in the cleaning liquid tank 2, and FIG. 3 is a partial sectional view of the scum suction device 4. The scum suction device 4 includes a scum receiver 10 that can move up and down in the cleaning liquid tank 2, and a suction pump 1 that suctions scum S flowing into the scum receiver 10.
1, a liquid level meter 12 for detecting the level of the cleaning liquid in the cleaning liquid tank 2, and a lifting drive mechanism 13 for raising and lowering the scum receiver 10 based on a signal from the liquid level meter 12.

The scum receiver 10 comprises a scum inlet 14 having a scum inlet in front of the center of the width, and a scum receiving weir 15 extending from both left and right sides of the scum inlet 14 to both side surfaces of the washing liquid tank 2. . Liquid level meter 1
2 adopts a method of detecting the height position of the float 16 with the displacement meter 17.

The raising / lowering drive mechanism 13 is supported by an electric motor 18 driven by a signal from the liquid level meter 12 and a support base 19 connected to the rotating shaft of the electric motor 18 and extended to the left and right upper ends of the washing liquid tank 2. Screw rod 2
0, and worm mechanisms 22, 22 configured by meshing screw rods 21, 21 threaded through right and left sides of the scum receiver 10. When the electric motor 18 is driven to rotate, the scum receiver 10 is rotated. Moves up and down.

Since the scum separation tanks 6 and 7 shown in FIG. 1 have the same left-right symmetric structure, FIG. 4 shows a cross-sectional view of only one scum separation tank 7 and the description of the scum separation tank 6 is omitted. FIG. 5 is a sectional view taken along line AA of FIG. The scum separation tank 7 has a scum receiving port 23 communicating with the suction pump 11 shown in FIGS. 2 and 3, an outlet 24 for the cleaning fluid that communicates with the cleaning fluid tank 2 shown in FIG. The pressure chamber 25 includes a pressure chamber 25, a scraper 26 that slides outside the liquid level pressure chamber to discharge scum, and a foreign substance discharge port 27 that discharges deposited foreign substances.

The liquid level pressurizing chamber 25 is a wall 25a having a closed space formed above the liquid level and a scum inlet 28 formed below the liquid level.
A pressure gas supply port 29 provided on the wall 25a, the opening of which is adjusted by a signal from a liquid level meter (not shown), and an air tube 30 connected to the pressure gas supply port 29. Have been. Valves 31 to 33, which open and close in response to signals from a liquid level gauge (not shown), are provided in each of the pipes of the pressure gas supply port 29, the scum receiving port 23, and the discharge port 24 of the cleaning rolling oil, as described later. The scum separation tanks 6 and 7 are used alternately.

The scraper 26 is connected to a rodless air cylinder 34, and reciprocates between the scum discharge port 36 according to a signal from the liquid level gauge (not shown) and floats in the scum separation tank 7. The scum can be dropped from the scum discharge port 36 into the scum discharge passage 37. Since the scum is stuck to the scum discharge port 36 and hinders the discharge of the scum, a roller 38 for breaking the stuck scum is provided. The roller 38 is reciprocated in the direction of the arrow in FIG. 5 by a rodless air cylinder 35 driven by a timer (not shown).

Next, the operation of the present apparatus will be described. The used cleaning liquid is supplied to the cleaning liquid tank 2 because scum and other foreign substances are mixed in the cleaning liquid used for cleaning the strip in the strip cleaning apparatus 1 shown in FIG. The electric motor 18 is driven by receiving a signal from the liquid level meter 12 so that the scum S floating from the scum inflow portion 14 of the scum suction device 4 flows in, and the height position of the scum inflow portion 14 is adjusted. You. Scum receiver 1 from scum inlet 14
The scum that has flowed into 0 is sucked by the suction pump 11 and supplied to the scum separation tank 7.

In the scum separation tank 7, when the liquid level of the contaminated cleaning liquid mainly composed of scum detected by a liquid level meter (not shown) reaches a specified level, the valve 32 is closed to stop the supply of the cleaning liquid. The contaminated cleaning liquid is supplied to the adjacent scum separation tank 6. Scum in the contaminated cleaning liquid floats and separates in the scum separation tank 7, and other foreign matter G
Settles due to the difference in specific gravity and accumulates at the bottom of the tank.

When the floating of the scum and the sedimentation of foreign matter are completed, a valve 31 is opened by a timer (not shown), and air is supplied from the pressurized gas supply port 29 into the air tube 30 so that the air tube 30 is inflated. By depressing the liquid level in the pressure chamber 25, the liquid level
Is pushed up, and the floating scum S is pushed upward from the upper surface of the scum discharge port 36. afterwards,
The scraper 26 having the width of the scum separation tank 7 is driven by the air cylinder 34 to scrape out the floating scum S toward the scum discharge port 36 and drop the scum S from the scum discharge passage 37 into the waste liquid tank 8.

The scum scraped by the scraper 26 adheres to the scum discharge port 36, and the scum is removed by moving the upper surface of the scum discharge port 36 while rotating the roller 38 with the air cylinder 35 to reduce the scum discharge efficiency. Remove by crushing.

When the discharge of the floating scum by the scraper 26 is completed, the valve 50 provided at the bottom of the scum separation tank 7 is opened, and the other foreign matter G that has settled and deposited is dropped into the waste liquid tank 8 and the waste liquid pit 9. When the process of separating and removing scum and other foreign matter in the scum separation tank 7 is completed, the cleaning liquid in the scum separation tank 7 is opened by opening the valve 33 so that the cleaning liquid is discharged from the cleaning liquid discharge port 24. 2 to the cleaning side,
It is supplied to the strip cleaning device 1 from the tank.

While the scum and other foreign matter are being removed in the scum separation tank 7, the scum separation tank 6 receives the contaminated cleaning liquid mainly composed of scum supplied by the scum suction device 4, and receives a liquid level meter. When the liquid level height (not shown) reaches a specified level, the supply of the contaminated cleaning liquid is stopped, and the same processing as in the scum separation tank 7 is performed. While removing scum and other foreign matter in the scum separation tank 6, the scum separation tank 7 receives the contaminated cleaning liquid supplied by the scum suction device 4. Thus, continuous operation is possible by using the two scum separation tanks 6 and 7 alternately.

FIG. 6 shows an outline of a rolling oil purifying apparatus according to the present invention. The same reference numerals as those in FIG. 1 have the same names and structures, so that the description thereof will be omitted. The difference from FIG. 1 is that a cold rolling mill 39 is provided instead of the strip cleaning liquid apparatus 1 of FIG. 1, and a first dirty tank 42 and a second dirty tank 43 in which a magnet separator 41 is provided in a rolling oil circulation path 40 are provided. In addition, a rolling oil tank 44 is provided in place of the cleaning liquid tank 2 in FIG. 1, and a filter paper for collecting foreign matter such as iron powder in the rolling oil is provided in the rolling oil tank 44. The used filter 45 was wound in a coil shape and supported at one end of a rolling oil tank, and the filter 45 was unwound by a feed roll 46 and immersed in rolling oil to collect foreign matter such as iron powder in the rolling oil. Then, it is configured to be sent to the stack 47. Reference numeral 48 denotes a receiving net for supporting the filter 9.

The rolling oil tank 44 is provided with a scum suction device 4 having the same structure as in FIGS. 2 and 3. After the rolling oil stored in the rolling oil tank 44 is sucked by the scum suction device 4, The scum separation tanks 6 and 7, the waste liquid tank 8, and the waste liquid pit 9 having the same structure as in FIG. 1 are provided in the rolling oil bypass route 49 returned to the rolling oil tank again.

In FIG. 6, since the rolling oil used for rolling the strip in the cold rolling mill 39 contains foreign matters such as scum and iron powder, the used rolling oil is provided in the first dirty tank 42. After a part of the iron powder is collected by the magnet separator 41, it is supplied to the rolling oil tank 44 by the feed pump P. In the rolling oil tank 44, foreign substances such as iron powder in the rolling oil are collected by the filter 45, and the contaminated rolling oil mainly composed of scum is sucked by the scum suction device 4 shown in FIGS.
5 is supplied to the scum separation tank 7 shown in FIG. 5, and the scum and the foreign matter such as iron powder are removed by the scum separation tank 7. The purified rolling oil is returned to the clean side of the rolling oil tank 44 in FIG. Rolling oil tank 44 to second dirty tank 43
, And supplied to the cold rolling mill 39.

While the scum separation tank 7 removes foreign substances such as scum and iron powder, the scum separation tank 6 receives the contaminated rolling oil supplied by the scum suction device 4 and uses a liquid level meter (shown in the figure). When the liquid level height (abbreviated) reaches a specified level, the supply of the contaminated rolling oil is stopped, and the same processing as that in the scum separation tank 7 is performed. While removing foreign substances such as scum and iron powder in the scum separation tank 6, the scum separation tank 7 receives the contaminated rolling oil supplied by the scum suction device 4.

The outline of the operation of the rolling oil cleaning apparatus has been described above. The details of the operation are as follows. In the cleaning liquid cleaning apparatus, the "cleaning liquid" is replaced with "rolling oil" and the "other foreign substances" are replaced with "iron powder". In other words, it is the same as in the case of the cleaning liquid cleaning device. In FIG. 4, the air tube 30 is desirably attached to prevent the scum from sticking to the tank wall due to cooling of the scum, but may be omitted.

[0032]

According to the present invention, (1) a scum suction device is used to supply a rolling oil or a cleaning liquid having a high scum concentration to a scum separation tank. Smooth rise of the liquid level in the chamber prevents turbidity of the scum and iron powder due to the waving and agitation of the rolling oil and the cleaning liquid. (3) The scum floating time and iron are reduced by providing a plurality of scum separation tanks. By sufficiently securing the sedimentation time of foreign substances such as powder, the removal efficiency of scum and the like can be dramatically improved.

As a result, the scum, iron powder, and the like in the rolling oil and the cleaning liquid can be efficiently removed, so that the reuse rate of the rolling oil and the cleaning liquid is increased, and the consumption amount is reduced. In addition, since the rolling oil and the cleaning liquid can be cleaned at a high speed, it is possible to more reliably prevent the surface flaw of the strip in a cold rolling mill such as a Sendzimir mill or a strip cleaning liquid apparatus that requires a large amount of the rolling oil or the cleaning liquid to be supplied. it can.

[Brief description of the drawings]

FIG. 1 is an overall view of an apparatus for cleaning a cleaning liquid according to the present invention.

FIG. 2 is a perspective view of a scum suction device provided in the cleaning liquid tank of the present invention.

FIG. 3 is a partial sectional view of the scum suction device of the present invention.

FIG. 4 is a sectional view of the scum separation device of the present invention.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

FIG. 6 is an overall view of a rolling oil cleaning device according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 strip cleaning device 2 cleaning liquid tank 3 cleaning liquid circulation path 4 scum suction device 5 cleaning liquid bypass path 6 scum separation tank 7 scum separation tank 8 waste liquid tank 9 waste liquid pit 10 scum receiver 11 suction pump DESCRIPTION OF SYMBOLS 12 ... Liquid level meter 13 ... Elevating drive mechanism 14 ... Scum inflow part 15 ... Scum receiving weir 16 ... Float 17 ... Displacement meter 18 ... Electric motor 19 ... Support base 20 ... Screw rod 21 ... Screw rod 22 ... Worm mechanism 23 ... Scum receiving port 24 ... Cleaning liquid discharge port 25 ... Liquid level pressurizing chamber 25a ... Wall of liquid level pressurizing chamber 26 ... Scraper 27 ... Foreign matter discharge port 28 ... Scum inlet 29 ... Pressure gas supply port 30 ... Air Tubes 31-33 ... Valve 34 ... Air cylinder 35 ... Air cylinder 36 ... Scum outlet 37 Scum discharge passage 38 Roller 39 Cold rolling mill 40 Rolling oil circulation path 41 Magnetic separator 42 First dirty tank 43 Second dirty tank 44 Rolling oil tank 45 Filter 46 Feed roll 47 Stack 48 ... Receiving net 49 ... Rolling oil bypass path 50 ... Valve P ... Feeding pump S ... Scum G ... Foreign matter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B21B 45/02 330 B21B 45/02 330 (72) Inventor Takayuki Shimada 3434 Shimada, Oaza, Hikari-shi, Yamaguchi Japan (72) Inventor Naotoshi Nishimura, Nippon Steel Plant Design Co., Ltd., 46-46 Nakahara, Tobata-ku, Kitakyushu-shi, Fukuoka Prefecture Hotani Co., Ltd. F-term (reference) 3B201 AA08 BB92 CD22

Claims (5)

[Claims] 1. A cleaning liquid in a strip cleaning apparatus is stored in a cleaning liquid tank, scum floating in the cleaning liquid tank is sucked and stored in a plurality of scum separation tanks, and scum floating in the scum separation tank is scraped out. A method for cleaning a cleaning liquid, comprising the steps of alternately discharging, from each tank, foreign substances discharged from an upper end of a tank and settling in the scum separation tank from a lower end of the tank. 2. A cleaning liquid tank (2) is provided in a cleaning liquid circulation path (3) of a strip cleaning apparatus (1), a scum suction device (4) is provided in the cleaning liquid tank, and the cleaning liquid tank is discharged by the scum suction device. Cleaning liquid detour returning to the cleaning liquid tank (5)
Provided, a plurality of scum separation tanks (6),
(7), the scum suction device includes a scum receiver (10) having a scum inflow portion on the scum receiving inlet side, a suction pump (11) for sucking scum in the scum receiver, and a liquid level meter. An elevating drive mechanism (13) that raises and lowers the scum receiver in response to the signal of (12) is provided, and the scum separation tank communicates with the scum receiving port (23) that communicates with the suction pump and the cleaning liquid tank. A discharge port (24) for the cleaning liquid, a liquid level pressurizing chamber (25) for raising the liquid level, a scraper (26) that slides outside the liquid level pressurizing chamber, and a foreign substance for discharging accumulated foreign substances An apparatus for purifying a cleaning liquid, comprising a discharge port (27). 3. A rolling oil of a cold rolling mill is stored in a rolling oil tank, scum floating in the rolling oil tank is sucked and stored in a plurality of scum separation tanks, and floating in the scum separation tank. Scrape out the scum and drain from the top of the tank,
A method for cleaning rolling oil, wherein the operation of discharging foreign substances settling in the scum separation tank from the lower end of the tank is alternately performed for each tank. 4. A first dirty tank (42) and a rolling oil tank (44) from upstream in a rolling oil circulation path (40) of a cold rolling mill (39).
And a second dirty tank (43) in order, a scum suction device (4) is provided in the rolling oil tank, and the scum suction device causes the rolling oil bypass (49) to exit the rolling oil tank and return to the rolling oil tank. ), A plurality of scum separation tanks (6), (7) are provided in the rolling oil bypass, and the scum suction device (4) has a scum receiver (10) having a scum inflow portion on the scum receiving inlet side. A suction pump (11) for sucking scum in the scum receiver, and an elevating drive mechanism (13) for raising and lowering the scum receiver in response to a signal from a liquid level meter (12). A scum receiving port (23) communicating with the suction pump, a cleaning liquid outlet (24) communicating with the rolling oil tank, a liquid level pressurizing chamber (25) for raising the liquid level, A scraper (26) that slides outside the liquid level pressurizing chamber and a foreign matter discharge port (27) that discharges accumulated foreign matters are provided. Rolling oil cleaning device to. 5. A wall according to claim 2, wherein the liquid level pressurizing chamber (25) has a closed space formed above the liquid level and a scum inlet (28) formed below the liquid level. 25a) and a pressure gas supply port (29) provided on the wall body, the opening of which is adjusted by a signal of a liquid level meter (12), to provide a cleaning liquid and rolling oil cleaning apparatus.