JPH04279205A - Washing method of endless filter which is used for filtering coolant for cold rolling mill - Google Patents

Abstract

PURPOSE:To prevent clogging of filter and to prolong the life of filter by using detergent for washing a cold rolling mill and simultaneously washing an endless filter when washing the cold rolling mill. CONSTITUTION:At the time of rolling work, after opening a suction valve 18a for coolant pump, closing a suction valve 18b, opening a return valve 19a and closing a return valve 19b, coolant is sprayed on the filter 2 and the endless filter 2 is washed. And, at the time of washing work of the cold rolling mill 15, after closing the suction valve 18a for coolant pump, opening the suction valve 18b, closing the return valve 19a and opening the return valve 19b, mill washing liquid is sprayed on the endless filter 2 and strong washing effect is achieved. Then, used detergent is returned to a mill washing liquid tank 17 through a return piping 16, so the detergent is not mixed in the coolant.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method for cleaning an endless filter used to filter foreign matter mixed into the coolant in an emulsion-type rolling oil (hereinafter referred to as coolant) circulation supply equipment for a cold rolling mill. It is.

0002

2. Description of the Related Art FIG. 2 shows a conventional coolant circulation supply equipment for a cold rolling mill. In FIG. 2, the coolant for the cold rolling mill 15 is pressurized from the clean tank 12 by the coolant pump 13, and is supplied through the piping 14 to the rolling mill. The used coolant is sent to the dirty tank 11 through the coolant return pipe 16.

[0003] In order to filter out foreign substances in the used coolant using an endless filter, the following procedure is performed. The pressure of the coolant in the dirty tank 11 is increased by the filter liquid feed pump 6, and the coolant is sent into the upper shell 1a of the filter body 1 via the filter-bound piping 7, and is filtered when passing through the endless filter 2. This endless filter 2 is usually made of nylon cloth.

[0004] The filtered coolant is transferred to the lower shell 1b.
from the clean tank 12 via the filtrate return pipe 8.
Return to After filtration for a certain period of time, endless filter 2
Foreign matter in the coolant is deposited on the top as sludge, so filtration is temporarily interrupted and the upper shell 1a is raised.
While feeding the endless filter 2 clockwise in the figure, compressed air is blown onto the endless filter 2 from the air blow piping 3, and the sludge accumulated on the endless filter 2 is discharged into the sludge receiving box 5. Furthermore, the sludge remaining on the endless filter 2 is removed by the coolant pump 1.
The coolant pressurized in step 3 is blown onto the endless filter 2 from the coolant blow pipe 4, washed onto the drain pan 9, and returned to the dirty tank 11 via the drain return pipe 10.

[0005]

[Problems to be Solved by the Invention] However, in the above-mentioned conventional equipment, when rolling oil with a high melting point and high viscosity such as beef tallow is used, foreign matter may accumulate on the endless filter during operation, and long-term operation may occur. Residual rolling oil on the endless filter may solidify due to discontinuation, causing clogging of the endless filter.

[0006] Once the endless filter becomes clogged, it is difficult to remove the clog by air blowing and coolant blowing, and the filtration pressure of the clogged endless filter becomes excessive, making it impossible to continue filtration. Therefore, it was necessary to replace it. Therefore, in conventional equipment, the life of the endless filter was extremely short.

[0007] Therefore, in order to prevent clogging of the endless filter, it is necessary to use a filter with a large opening, and as a result, the filtration accuracy decreases and the amount of foreign matter in the coolant and the particle size of the foreign matter increase. There was a problem of surface defects occurring on the product due to foreign matter getting caught. An object of the present invention is to provide a method of cleaning an endless filter that solves these problems.

[0008]

[Means for Solving the Problems] The present invention provides a method for cleaning an endless filter in an apparatus for filtering cold rolling mill coolant using an endless filter. A method for cleaning an endless filter used for filtration of cold rolling mill coolant, characterized in that the endless filter is simultaneously cleaned using a detergent for cleaning the machine.

[0009]

[Operation] According to the present invention, in FIG. 1, during rolling work, the coolant pump suction valve 18a is opened, the coolant pump suction valve 18b is closed, and the return valve 19a is closed.
By opening and closing the return valve 19b, coolant is sprayed onto the endless filter 2 in the same manner as before.
Clean the endless filter 2.

When cleaning the cold rolling mill 15, the coolant pump suction valve 18a is closed, the coolant pump suction valve 18b is opened, the return valve 19a is closed, and the return valve 19b is opened. ) can be sprayed onto the endless filter 2 to obtain a powerful cleaning effect. Further, since the detergent that has washed the endless filter 2 returns to the mill cleaning agent tank 17 via the coolant return pipe 16, the detergent does not mix into the coolant.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be explained based on the drawings. FIG. 1 is a piping system diagram of an embodiment of the present invention, and FIG.
The difference from the conventional one is as follows. A coolant pump suction valve 18a is provided in the piping between the clean tank 12 and the coolant pump 13. Further, a return valve 19a is provided in the middle of the coolant return pipe 16.

Additionally, a mill cleaning agent tank 17 is newly installed, and this mill cleaning agent tank 17 includes a coolant pump 13 and a coolant pump suction valve 18a.
A pipe branched from a pipe between the two pipes communicates with the pipe through a coolant pump suction valve 18b. Further, a pipe branched from the coolant return pipe 16 upstream of the return valve 19a communicates with the upper part of the mill cleaning agent tank 17.

When a clogged endless filter was washed with a detergent using the method of the present invention using the coolant supply equipment shown in FIG. 1, it was found that the filter was able to be unclogged due to the cleaning effect of the detergent. Ta. In addition, conventional filters clogged after about a month of use and had to be replaced, but when the filters were regularly cleaned using the method of the present invention, the filters no longer became clogged and the filters had to be replaced. lifespan has been extended by more than 6 months.

Furthermore, in the past, filters with apertures of 150 μm or less could not be used to prevent clogging, but with the method of the present invention, filters with apertures up to 100 μm can be stably used without clogging. became. As a result, the average amount of solid foreign matter in the coolant was 50
The concentration was reduced from 0 ppm to 300 ppm on average, and the frequency of surface defects on products due to foreign matter caught in the coolant was reduced.

[0015]

[Effects of the Invention] As explained above, the present invention uses a detergent with a higher cleaning effect than a coolant to clean the endless filter, so that clogging of the filter can be easily recovered, and the clogging of the filter can be prevented. , it is possible to extend the life of the filter. Furthermore, since it is possible to stably use a filter with a smaller opening than before, filtration accuracy is improved and surface defects of products due to foreign matter caught in the coolant are reduced.

[Brief explanation of the drawing]

FIG. 1 is a piping diagram of an embodiment of a coolant supply facility suitable for carrying out the method of the present invention.

FIG. 2 is a piping diagram of a conventional coolant supply facility.

[Explanation of symbols]

1 Filter body 1a Upper shell 1b Lower shell 2 Endless filter 3 Air blow piping 4 Coolant blow piping 5 Sludge receiving box 6 Filter liquid feed pump 7 Filter going piping 8 Filtrate return piping 9 Drain pan 10 Drain return piping 11 Dirty tank 12 Clean tank 13 Coolant pump 14 Coolant mill going pipe 15 Rolling mill 16 Coolant return pipe 17 Mill cleaning agent tank 18a Coolant pump suction valve 18b Coolant pump suction valve 19a Return valve 19b Return valve

Claims (1)

[Claims] 1. A method for cleaning an endless filter in an apparatus for filtering cold rolling mill coolant using an endless filter, the method comprising:
A method for cleaning an endless filter used for filtration of cold rolling mill coolant, the method comprising cleaning the endless filter at the same time using a detergent for cleaning the cold rolling mill.