JPH09118937A - Production of casting chip briquette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a good casting chip briquette reused to raw material for casting by excluding bulky chip from the casting chip sticking the cutting oil, reducing oil content kneading, forming to the briquette, executing heating treatment and air-cooling. SOLUTION: Bulky grain having >= about 10mm grain diameter is separated and removed by screening the casting chip sticking the cutting oil, and the oil content in the chip having <= about 10mm grain diameter is reduced to <=1% of the total wt. by using a centrifugal separator. After kneading this chip for several ten sec., immediately, this chip is pressed and formed to a briquette and washed by water-spraying to remove flash and binder. Successively, this briquette is heated at about 400-500 deg.C in the oxidizing atmosphere to vaporize the moisture, and after perfectly burning the oil content, the briquette is air-cooled. By this method, good quality casting chip briquette is obtd. without using a dust collector and polluting the atmosphere, and the briquette can be reused as the raw material for casting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a briquette for casting chips, which is solidified so that the casting chips (pig iron dali powder) produced by cutting a cast product can be reused as a raw material for casting.

[0002]

2. Description of the Related Art Heretofore, as a method for producing a briquette of casting scraps of this kind, impurities are removed, and a binder suitable for the casting scraps containing oil and water content of 2% or less by centrifugal separation is used in a weight ratio. Add about 2%, knead for several minutes, stir to homogeneity, press to make briquettes,
This briquette is preferably 500-9 at around 700 ° C.
Casting scrap as a raw material for casting, which is heated in a reducing atmosphere at a temperature of 00 ° C. for 10 to 30 minutes to cause the added binder to undergo an endothermic reaction, and the briquettes after firing are gradually cooled in a reducing atmosphere and hardened while preventing their oxidation. A method for producing a compact is known (see Japanese Patent Publication No. 58-14493).

[0003]

However, in the conventional method for producing casting cutting chips briquette, a binder is added to bond the casting chips, so that the furnace body of the heating furnace is damaged or melted. There is a problem that it becomes uneconomical due to frequent occurrence of slag. In addition, although the amount of adhering cutting oil is reduced to 2% or less by centrifugal separation, the amount of adhering cutting oil is insufficient, and excessive oil vapor is mixed in the exhaust gas generated when firing briquette in a reducing atmosphere. Therefore, although it is guided to the secondary combustion chamber and burned, incomplete combustion of oil is likely to occur and unburned carbon remains in the exhaust gas discharged into the atmosphere to cause air pollution. There is a problem that must be attached. Therefore, the present invention suppresses the occurrence of slag during use,
Do not cause damage to the furnace body of the heating furnace during manufacturing,
A main object of the present invention is to provide a method for producing a casting cutting scrap briquette capable of releasing exhaust gas due to firing of a briquette into the atmosphere without collecting dust.

[0004]

In order to solve the above-mentioned problems, the first method for producing a casting cutting scrap briquette of the present invention is a method for sieving a casting cutting scrap to which cutting oil adheres to remove coarse scraps, The oil content is reduced to 1% or less of the total weight by centrifugation, and after kneading for several tens of seconds, it is immediately pressed into briquettes. The briquettes are washed with water and then heated in an oxidizing atmosphere to evaporate the water content and the oil content and to remove the oil content. It is characterized by complete combustion and then air cooling. The second method for producing casting cutting chips briquette is to remove the coarse chips by sieving the casting chips to which cutting oil adheres, and reduce the oil content to 1% or less of the total weight by centrifugal separation. If it is fine, add about 0.5% of the binder to the total weight ratio or coarse casting cuttings, knead for several tens of seconds and immediately press into briquettes. Wash the briquettes with water and then heat in an oxidizing atmosphere. It is characterized in that the water content and the oil content are evaporated and the oil content is completely burned, and then air cooling is carried out. Further, the third method for producing a casting cutting scrap briquette is the method according to the first or second method, wherein when the cutting oil is water-soluble, an appropriate amount of water is added to dilute the adhering cutting oil before the centrifugation. It is characterized by doing. On the other hand, the water is
It is preferably warm water. It is preferable that the pressing is performed by pressing the raw material loaded in the cylindrical mold with plungers inserted from both ends of the mold. The briquette has a short cylindrical shape, and the ratio of length to diameter is 1.0 to 1.5,
It preferably has a weight of 10 to 15 kg.

If the oil content after dehydration is more than about 1% of the total weight, the temperature inside the furnace becomes abnormally high, which may damage the furnace body of the heating furnace. If the total amount of the binder is more than about 0.5%, not only the furnace body of the heating furnace is easily damaged, but it is economically disadvantageous. Moreover, the heating temperature of the briquette is preferably 400 to 500 ° C.
If the temperature is lower than 0 ° C, the evaporation of oil is insufficient and the combustion is not performed well, while if it exceeds 500 ° C, the fuel is wasted. Water glass (sodium silicate) or the like is used as the binder.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a method for manufacturing a briquette for casting cutting scraps according to the present invention. In order to manufacture a cast metal cutting scrap briquette, which is a raw material for casting, from a cast metal cutting scrap to which cutting oil adheres, first, the cast metal scrap 1 to which the cutting oil adheres is supplied to the vibrating screen 2 to obtain a coarse particle having a particle size of about 10 mm or more. Separate and remove scraps. Then, the casting chips 1 having a particle size of about 10 mm or less from which the coarse chips are separated and removed are supplied to the centrifugal separator 3 to centrifuge the adhering cutting oil to reduce the oil content to about 1% or less of the total weight. Prior to this centrifugation, if the adhering cutting oil is water-soluble, the adhering cutting oil is diluted by adding an appropriate amount of water, preferably heated hot water, to the casting cutting waste by a water sprinkler, whereby the centrifuge can be easily separated in a short time. Can be done.

Next, the casting cutting waste 1 is supplied to the kneading machine 4 and kneaded for several tens of seconds, and immediately thereafter, it is strongly compression-molded by the briquetting press 5 to have a short cylindrical shape and a length L with respect to the diameter D. Ratio (L / D) of 1.0 to 1.5, weight of 10
A molded product (briquettes) of 15 kg. When the casting cutting waste 1 is fine (particle diameter of about 1 mm or less), water glass (binder) is about 0.5% of the total weight ratio or coarse (particle diameter of about 1 to 10 mm) casting cutting waste 1 is in an appropriate amount. (About 50% by weight) is added, and the mixture is kneaded for several tens of seconds. Then, immediately, it is strongly compression molded by a briquetting press 5 to obtain a similar briquette. Casting chips 1 with a grain size of about 10 mm or less
In the process of compression molding (pressing), the casting cutting waste 1 is strongly molded such that fine particles enter and are surrounded by the coarse particles, and the remaining cuttings that cannot be inserted between the particles. In the process of oil exudation on the surface of the briquette, and during the compression molding of the fine casting chips 1 having a particle size of about 1 mm or less, the binder is sufficiently permeated between the particles of the casting chips 1 and The binder that could not be filled between the particles and the residual cutting oil ooze out on the surface of the briquette, and the fine cutting waste 1 with a particle diameter of about 1 mm or less and the coarse casting cutting waste 1 with a particle diameter of about 1 to 10 mm are mixed. In the process of compression molding of material, the above-mentioned particle size is 10 mm.
Same as for the following: The briquetting press 5 is a large-sized horizontal double-pressing type, and after the raw material is loaded into the cylindrical horizontal die from the raw material inlet provided on the cylinder wall, the briquetting press 5 is inserted from both ends of the die. Pressurized with a plunger.

When the molded product is washed by sprinkling water with a water sprinkler and has a particle size of about 10 mm or less or a mixture of particle size of about 1 mm or less and particle size of about 1 to 10 mm, burrs on both edges are formed. After removing the cutting oil that has exuded on the surface, and if it consists of a binder with a particle size of about 1 mm or less and the binder added, heat after removing the burr on both edges and the binder that exuded on the surface. It is supplied to the furnace 6, and first, in an oxidizing atmosphere in a heating zone, 400 to 500
The mixture is heated to a temperature of ° C to evaporate water and oil, and the oil is completely combusted. Then, the oil is air-cooled in the cooling zone and discharged from the outlet as a casting cutting scrap briquette (product) 7 which is a raw material for casting. When a binder is added, the binder is heated by the heating in the heating zone so that the binder reacts with dehydration reaction and / or CO in the combustion gas.
_It is hardened by a chemical reaction with _2, and the casting cutting waste 1 is solidified. The heating furnace 6 is a large mesh belt type LP.
In the G gas fired furnace, the exhaust gas from the heating zone is added to the upper part of the tunnel-shaped furnace body having the heating zone and the cooling zone.
A secondary combustion cylinder for secondary combustion, and an exhaust device for mixing and exhausting the exhaust gas of the secondary combustion cylinder and the exhaust gas of the cooling zone are attached, and the exhaust gas generated from the heating furnace 6 is not discharged in the secondary combustion cylinder. It is completely burned and released into the atmosphere without carbon.

[0009]

As described above, according to the first method for manufacturing casting cutting scrap briquettes of the present invention, since it is not necessary to use a binder, the furnace body of the heating furnace is damaged during manufacturing, and It does not become uneconomical due to excessive slag generation in the melting furnace, the amount of cutting oil adhered by centrifugal separation is sufficient, and the cutting oil in the briquette after pressing is briquette in an oxidizing atmosphere. Since it is completely combusted during firing, it is possible to obtain good casting cuttings briquette as a raw material for casting, and at the time of manufacturing, exhaust gas from firing briquettes is released to the atmosphere without collecting dust with a dust collector. However, it does not cause air pollution.

According to the second method for producing a casting cutting scrap briquette, a briquette having substantially the same effect as that of the first method can be obtained even with fine casting scraps.

Further, according to the third method for producing casting cutting scrap briquettes, in addition to the effects of the first or second method, the cutting scrap adheres to the casting cutting scraps prior to the reduction of the adhering cutting oil. Since water-soluble cutting oil is diluted with water,
The water-soluble cutting oil attached can be removed more easily than in the past.

On the other hand, by diluting the water-soluble cutting oil with warm water, the attached water-soluble cutting oil can be removed more easily. Briquetting can be performed in a short time by pressing the casting cutting dust with the plungers inserted from both ends of the mold to load the raw material loaded into the cylindrical mold, and the briquette strength (falling The strength that does not sometimes break) can be increased. Also, the briquette is a short cylinder, the ratio of length to diameter is 1.0 to 1.5, and weight is 10
Since it is ~ 15 kg, it is excellent in handling property as a raw material for casting.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a method for manufacturing a casting cutting waste briquette according to the present invention.

[Explanation of symbols]

 1 Casting cutting waste 2 Vibrating screen 3 Centrifugal separator 4 Kneading machine 5 Briquetting press 6 Heating furnace 7 Casting cutting waste briquette

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[Procedure amendment]

[Submission date] February 16, 1996

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Added

[Correction contents]

FIG.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Akihiro Tomita 1780 Uetakano, Yachiyo-shi, Chiba Kawasaki Heavy Industries, Ltd. Yachiyo factory (72) Inventor Kazuhiro Suzuki 3-33, Konosu-cho, Toyota-shi, Aichi Toyokin shares In the company

Claims (6)

[Claims] 1. A casting cutting scrap to which cutting oil adheres is sieved to remove coarse scrap, and centrifugal separation is performed to remove oil by 1% of the total weight.
%, And after kneading for several tens of seconds, press it immediately to make a briquette, wash this briquette with water, then heat it in an oxidizing atmosphere to evaporate the water and oil and completely burn the oil, and then air cool. A method for manufacturing a briquette for casting cutting scraps, which comprises: 2. A casting cutting scrap to which cutting oil adheres is sieved to remove coarse scrap, and centrifugal separation is performed to remove oil by 1% of the total weight.
% Or less, and if the cutting waste is fine, add about 0.5% of the binder in the total weight ratio or coarse casting waste to this, knead for several tens of seconds and immediately press to make a briquette. A method for producing a casting cuttings briquette, characterized in that after washing with water, it is heated in an oxidizing atmosphere to evaporate the water content and the oil content, completely burn the oil content, and then air-cool. 3. Prior to the centrifugal separation, when the cutting oil is water-soluble, an appropriate amount of water is added to dilute the adhering cutting oil, and the briquette for casting cutting chips according to claim 1 or 2. Production method. 4. The method for manufacturing a casting cutting scrap briquette according to claim 3, wherein the water is hot water. 5. The casting cutting waste according to claim 1, 2, 3 or 4, wherein the pressing is performed by pressing a raw material loaded in a cylindrical mold with plungers inserted from both ends of the mold. Briquette manufacturing method. 6. The briquette has a short cylindrical shape and has a ratio of length to diameter of 1.0 to 1.5 and a weight of 10 to 15 kg. A method for producing a briquette for casting cutting waste as described.