JPS6313702A - Die attachment for inorganic extrusion molding - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Purpose of the Invention The present invention provides a new ceramic powder such as metal oxide 2, such as aluminum oxide, or a hydraulic material such as cement gypsum, water, a fiber agent, or a fluidizing aid such as methyl cellulose. When molding the composition containing the above in a screw extruder, plunger extruder, etc., the same cross section as the molding die with a thickness of about 1 to 50 mm was machined on the front edge of the die attached to the tip of the molding machine. This invention relates to an attachment for an inorganic extrusion molding die that has a wear-resistant attachment fixed so that the dimensions of the molded product do not change even if the die is worn.

Furthermore, in the case of hollow products, which is a characteristic of extrusion molding.

This invention also improves the core that forms the hollow part by using a similar attachment.

Problems to be Solved by the Invention Usually, in order to manufacture long molded products with irregular cross sections such as rods, rings, and plates for building materials and civil engineering materials using hydraulic inorganic materials such as cement and gypsum, These materials are mixed with water and other mixed materials in a mixer, and after kneading, they are fed to a vacuum extruder, usually a two-stage screw set, and then molded through a die attached to the tip that forms the desired shape. Be taken.

Considering workability, rigidity, abrasion resistance, etc., the steel used for this die is 545C.

Machining using 550C, die steel, etc. 1 Machining by electrical discharge machining etc. is used, but if the above composition contains silica sand, calcined pearlite or other mixtures with high Mohs hardness as a composition. Therefore, if the die is operated for a long time while the composition passes through the die, the die surface will gradually wear out and the die will become larger than the originally designed cross section. Moreover, in severe cases at 8I, the thickness of the product changes by about 0.5 mm in a few days.

Usually, molded products are used as building materials, etc., as a product with ±5 layers.
That is, since the tolerance is about ±500μ, if the thickness is reduced by about 0.5+wo+ as described above, the molded product will be defective in terms of thickness and other aspects.

However, it is not economically viable to replace the die itself every time it wears out.

On the other hand, with the recent evolution of quenching technology, 1 vacuum quenching equipment has been developed. 9 In normal quenching in air, air pressure is applied and deformation occurs, and since the steel is an aerobic material, it oxidizes and instead causes damage to the steel. It becomes brittle, and the quenching is visible on the surface layer. On the other hand, according to the vacuum quenching method, there is no need to worry about oxidation because the quenching is done in a vacuum (and since it is not under pressure, there is less deformation and dimensional change). An improvement in hardness can be obtained.

Examples of vacuum hardenable die steels shown in the claims of this patent include JIS tool steels 5KDI, 5KD11, and 5K.
D12.5KD2.5KD61 etc. are equivalent, but after vacuum quenching, these steel materials reach a hardness of IIRc of 58 to 62.9 Steel materials such as 840C, which are normally used in the construction of dies, have a hardness of about HRCIO, and even SK steel. The hardness is only about 20, and even if hard chrome plating is applied as a finishing treatment, the hardness increases to about 850 to 880 with Winkers, but the plating thickness is only a few microns or tens of microns at most, so it is difficult to wear. In intense materials,
Based on actual molding experience, the lifespan is only about twice as long.

Composition of the invention The present invention will be explained in detail with reference to the drawings.

Figure 1 shows the cutting edge part of the die (1
), the portion of cross section (2) is worn out due to wear. Fig. 2 is a perspective view showing the state in which the attachment (3) of the present invention is attached, and (3) is the same cross section as the cross section (2) in Fig. 1 described in claim 1) of the present invention. The hardness is increased by vacuum hardening using vacuum hardenable die steel with a thickness of 1 mm to 50 mm.
This is an attachment with improved dust resistance. In fact, based on molding experience, a 10 mm thick attachment has 20 times more wear resistance.

In one example, the above attachment withstood continuous operation for more than two months, compared to one week for chrome-plated dies.

In this case, if more than 2 months have passed, this attachment will wear out by 0.5 mm or more even though it has been vacuum hardened, but in this case, you only need to replace the attachment.
There is no need to replace up to 11 dice, making it extremely economical.

In addition, as shown in FIG. 3, in the case described in claim 2), if the die (1) has a hollow structure and a core (4) is incorporated inside, the die (1) shown in FIG. As shown, the main body (5) is made of ordinary steel, and the attachment (6), which is vacuum hardened, which is a feature of the present invention, is screwed to the tip.If (6) wears out, only the attachment (6) can be replaced. All you have to do is make cents as shown in Figure 5.

Example In the example shown in FIG. 2 (3), the material was heated in vacuum at 1,030° C. for 12 hours and then quenched in oil at 530° C. for 3 hours. The hardness is 60 in HrC. This was extruded into siding material using a Mikami Kogyo model 200 extruder, and 1
I worked 8 hours a day and achieved results for 3 months.

Effects of the Invention Originally, extrusion molding is characterized by continuous operation for long periods of time, and since many products require precision in cross section, the present invention has the great advantage of maintaining product precision with simple attachment replacement. .

[Brief explanation of the drawing]

Figure 1 is a perspective view of the part that forms the cross section of the cutting-edge product of the die, Figure 2 is a perspective view showing the state in which the attachment of the present invention is attached, and Figure 3 is a perspective view of the tip of the die in the case of a hollow structure. 4 is a perspective view of the mandrel according to the present invention, and FIG. 5 is a perspective view of the tip of the die assembled using the mandrel of FIG. 2) Die cross section (3) Attachment as described in claim 1) (4) Hollow mandrel (5) Mandrel body (6) Attachment for mandrel as described in claim 2) February 1988 Patent applicant: Health Center Co., Ltd. Representative Yoshi Suzuki −

Claims (1)

[Claims] 1) When extruding and molding new ceramics such as metal oxides, or compositions made by adding water, fibers, fluidization aids such as methyl cellulose, etc. to cement, gypsum, etc., The desired molded product is machined on the front surface of the die to have the same cross section as the molding die with a thickness of about 1 to 50 mm. The material is die steel and a material that can be vacuum hardened is used. After vacuum hardening, it is fixed to the front surface of the die. , attachments to maintain the dimensions and accuracy of molded products. 2) In the case where the die has a hollow part in claim 1), in the core for forming the hollow part, the core is made shorter than the required size, the tip has the same cross section, and the material is different from that of the die. An attachment that fixes vacuum-hardened parts made of steel and vacuum-hardenable materials to the tip of the core to maintain the dimensions and accuracy of the molded product.