JPS63165057A - Production of cylinder - Google Patents

Abstract

PURPOSE:To improve the wear resistance, corrosion resistance and adhesion strength of padding layer of a cylinder by building up autogeneous melting alloy on the inner face of cylinder through centrifugal casting at plural times of lamination. CONSTITUTION:Granule 4 of autogeneous melting alloy adding a little quantity of B, Si, C, etc., to alloy of Ni-Cr kind or Co-Cr kind, is sealed into a cylinder raw body 3 and while heating under nonoxidizing atmosphere, the centrifugal casting is executed to form a first buildup layer 5. Next, in the inner part of center hole 2, granule 6 of wear resistant autogeneous melting alloy adding carbide of W, Ti, etc., or boride of Cr, Fe, Ni, etc., to the same kind or different kind of autogeneous melting alloy is filled, to form a second buildup layer 7 by the same centrifugal casting. In this way, the buildup layers 5, 7 have strong adhesion strength and also the buildup layer 7 improves the wear resis tance and corrosion resistance. Therefore, the wear resistance and corrosion resistance of the cylinder 8 and the adhesion strength of buildup layers 5, 7 are improved.

Description

Detailed Description of the Invention Object of the Invention (Field of Industrial Application) The present invention relates to a method for manufacturing a cylinder that is used to manufacture cylinders with excellent corrosion resistance and abrasion resistance. The present invention relates to a method for manufacturing cylinders that are used to manufacture cylinders that are required to have high corrosion resistance and/or high wear resistance and are components of injection molding machines and press machines for manufacturing ceramics and fine ceramics.

(Prior Art) Cylinders, which are component parts of injection molding machines and extrusion machines for engineering plastics, have conventionally been mainly made of nitrided steel.

However, in recent years, glass fibers have become popular.

The use of engineering plastics containing reinforcing fibers such as carbon fiber, wear-resistant fibers such as alumina and zirconia, and fillers made of particles is increasing, so the nitrided steel mentioned above has improved wear resistance and corrosion resistance. It has become inadequate in many aspects.

In order to solve these problems, pie metallic cylinders, which have excellent wear and corrosion resistance, have come to be used.

FIGS. 5(a) to 5(d) are diagrams showing the general manufacturing process of a pi-metallic cylinder. First, a round bar base material 21 ( The cylinder assembly 23 is manufactured by mechanically cutting a straight center hole 22 in the center of the cylinder (see FIG. 5(a)). Self-fusing alloys (melting point = 900-1100
(see Figure 5(c)), and heat it to 1100-1200°C with both ends closed to create an inert atmosphere inside. The powder 24 made of a self-fusing alloy is melted.

Next, the cylinder assembly 23 is attached to a rotating device and rotated, and the molten self-fusing alloy is closely attached to the inner surface of the cylinder assembly 23 by centrifugal casting, and after cooling, a build-up layer 2 of uniform thickness is formed.
5 (see FIG. 5(d)), and since the surface of this build-up layer 25 has many defects, those defects are removed by cutting, and then polished and finished, resulting in an engineering finish. The cylinder 26, which is a component of a molding machine or an extrusion machine, was used to inject plastics.

(Problems to be Solved by the Invention) In such a conventional cylinder 26, a small amount of alloy components such as B, Si, and C are added to a nickel-chromium alloy or a cobalt-chromium alloy on its inner surface. Although the built-up layer 25 made of a self-fusing alloy has excellent corrosion resistance, it is still difficult to use when used as a cylinder in an injection molding machine for engineering plastics or fine ceramics that contain fillers. The problem was that the wear resistance was insufficient.

Therefore, in order to further improve such wear resistance,
Although it is possible to add a large amount of carbides such as WC and NbC or borides such as Cr2B to the self-fusing alloy, in this case, the base material 21 constituting the cylinder 23 and the overlay layer 25 constituting the In order to achieve sufficient alloying with the self-fluxing alloy, the melting point of the self-fusing alloy must be set at 4° below the melting point of the base metal.
It is necessary to lower the temperature by about 00 to 600°C. Therefore, even if large amounts of the above-mentioned carbides and borides are added to improve the hardness and wear resistance of self-fusing alloys, the melting points of these carbides and borides are quite high, and the specific gravity is large. Therefore, after centrifugal casting, carbides and borides tend to concentrate on the base metal side (outer circumferential side), so they cannot be sufficiently alloyed at the interface between the base metal 21 and the built-up layer 25. Therefore, the hardness and wear resistance of the outermost surface of the built-up layer 25 do not improve much, and the adhesion between the base material 21 and the built-up layer 25 becomes poor, and peeling easily occurs. There was a problem with it becoming a thing.

In addition, when granular material 24 in the form of lumps or powder is sealed inside the cylinder assembly 23 (see FIG. 5(C)), the bulk density is approximately 3 to 4.5 at most, so the melting The subsequent volume will be about 1/2 to 1/3, so in the case of a cylinder 26 in which a thick built-up layer 25 is desired to be formed, or a cylinder 26 in which the shape of the center hole 22 is not straight with the same diameter. In this case, the conventional method had a problem in that it was difficult to form a build-up layer 25 of uniform thickness.

(Object of the Invention) The present invention has been made by focusing on the above-mentioned problems of the conventional technology. It is possible to manufacture cylinders, and it is also possible to manufacture cylinders with a thick build-up layer, or a build-up layer with a uniform thickness on the inner surface of a cylinder that has a concave and/or image part or a tapered part that is not straight. It is an object of the present invention to provide a method for manufacturing a cylinder that is capable of manufacturing a cylinder in which a cylinder is formed.

[Structure of the Invention] (Means for Solving the Problems) The method for manufacturing a cylinder according to the present invention is such that when manufacturing a cylinder by overlaying a self-fusing alloy on the inner surface of the cylinder by centrifugal casting, the self-fusing alloy is applied multiple times. It is characterized by being divided into two parts, each of which is laminated and overlaid on the inner surface of the cylinder by centrifugal casting.

In a method for manufacturing a cylinder according to an embodiment of the present invention, when manufacturing a cylinder by building up a self-fusing alloy on the inner surface of the cylinder by centrifugal casting, a small amount of B is added to an alloy such as nickel-chromium or cobalt-chromium. After a self-fusing alloy to which alloying components such as Si and C are added is overlaid on the inner surface of the cylinder by centrifugal casting, W, N b , and T a are added to the self-fusing alloy that is the same as or different from the above-mentioned self-fusing alloy.
, V, Ti, and other carbide-forming elements such as Or, Fe.

A wear-resistant self-fluxing alloy containing one or more wear-resistant components selected from borides of boride-forming elements such as Ni and Go is further layered and overlaid on the inner surface of the cylinder by centrifugal casting. That is.

FIGS. 1(a) to 1(f) are diagrams illustrating a method for manufacturing a cylinder according to an embodiment of the present invention in the order of steps. The cylinder assembly 3 is manufactured by mechanically cutting a straight center hole 2 in the center of the base material 1 (see FIG. 1(a)) (see FIG. 1(b)), and then the cylinder assembly 3 Inside the center hole 2, a small amount of B or Sf is added to an alloy such as nickelφchromium or cobalt-chromium.
, self-fluxing alloys containing alloying components such as C (melting point:
900 to 1100°C) in the form of lumps or powder (see Figure 1 (C)), with both ends closed to create a non-oxidizing atmosphere inside.
℃ to melt the powder 4 made of a self-fusing alloy inside.

Next, the cylinder assembly 3 is attached to a rotating device and rotated, and the molten self-fusing alloy is centrifugally cast while being in close contact with the inner surface of the cylinder assembly 3, and after cooling, a first wall of uniform thickness is formed. At this time, the first fleshy layer 5 is formed in close contact with the inner surface of the cylinder assembly 3 in an alloyed state.

Subsequently, after leaving one end open, a self-fusing alloy (W), which is the same as or different from the above-mentioned self-fusing alloy, is inserted into the center hole 2.
Carbides of carbide forming elements such as Nb, Ta, V, Ti and Cr, Fe, Ni, G.

A first granular material 6 in the form of lumps or powder made of a wear-resistant self-fluxing alloy containing about lθ to 70% by weight of one or more wear-resistant components selected from borides of boride-forming elements such as (See Figure (e)), both ends are closed to create a non-oxidizing atmosphere inside and heated to 1100 to 1200°C to melt the powder 6 made of a self-fusing alloy inside.

Subsequently, the cylinder assembly 3 is attached to a rotating device and rotated, and the molten self-fusing alloy and the wear-resistant component are solidified while being in close contact with the first overlay layer 5 by centrifugal casting, and after cooling, a uniform thickness is obtained. (FIG. 1(f)
)) At this time, since the wear-resistant component has a higher specific gravity than the self-fusing alloy, the wear-resistant component is concentrated on the first built-up layer 5 side. Note that when the powder 6 made of wear-resistant self-fluxing alloy is melted, there is a possibility that the surface portion of the first sensual layer 5 will also be melted; Since a part of the layer remains alloyed, there is no problem even if it is melted, and due to the presence of this first fleshy layer 5, the second overlay, layer 7, has high adhesion even if it contains wear-resistant components. It is formed with.

Since the surface of this second overlay layer 7 has many defects, the defects are removed by cutting, and the surface is polished and finished in an injection molding machine or an extrusion machine for engineering plastics, fine ceramics, etc. The cylinder 8 is a component of the cylinder 8.

In a method for manufacturing a cylinder according to another embodiment of the present invention, when manufacturing a cylinder by overlaying a self-fusing alloy on the inner surface of the cylinder by centrifugal casting, an alloy such as a nickel-chromium alloy or a cobalt-chromium alloy is used. Small amount of B, Si, C
After applying a self-fusing alloy to the inner surface of the cylinder by centrifugal casting, a self-fusing alloy that is the same as or different from the self-fusing alloy is further laminated to the inner surface of the cylinder by centrifugal casting. It is characterized by the fact that

7JIJ4 Figures (a) to (g) are diagrams showing a method for manufacturing a cylinder according to another embodiment of the present invention in the order of steps. First, a round bar made of structural steel such as carbon steel or chromium-molybdenum steel is The cylinder assembly 13 is manufactured by mechanically cutting a center hole 12 with different opening diameters at both ends in the center of the base material 11 (see FIG. 4(a)).
b)), then a self-fusing alloy (melting point: Figure 4 (
C)), both ends are closed to create a non-oxidizing atmosphere inside and heated to 1100 to 1200°C to melt the powder 14 made of a self-fusing alloy inside.

Next, the cylinder assembly 13 is attached to a rotating device and rotated, and the molten self-fusing alloy is solidified while being in close contact with the inner surface of the cylinder assembly 13 by centrifugal casting. Part 1 on the left side of Figure 4)
When the overlay layer 15 is formed (see FIG. 4(d)), the first overlay layer 15 is formed in close contact with the inner surface of the cylinder assembly 13 on the large opening diameter side in an alloyed state.

Next, after leaving one end open, the center hole 12 is filled with
A granular material 16 in the form of a lump or powder made of a self-fusing alloy that is the same as or different from the above-mentioned self-fusing alloy is enclosed.
(see e)), both ends are closed to create a non-oxidizing atmosphere inside and heated to 1100 to 1200''0 to melt the powder 16 made of a self-fusing alloy inside.

Subsequently, the cylinder assembly 13 is attached to a rotating device and rotated, and the molten self-fusing alloy is centrifugally cast into the first
The sensuous layer 15 and the inner surface of the center hole 12 on the small diameter side are solidified, and after cooling, the second sensual layer 17 is formed (see FIG. 4(f)). When the self-fusing alloy is melted to form the first sensual calendar 1
Although there is a possibility that the part 5 may be melted, the cylinder assembly 13
Since a part of the first overlay layer 15 is alloyed and remains on the inner surface, there is no problem even if it melts, and this first overlay layer 15
Due to the presence of , the second flesh-sensitive layer 17 is formed in a straight shape.

Next, the second build-up layer 17 and the first build-up layer 15 are cut to form a center hole 18a having a predetermined shape with a large opening diameter portion and a booth diameter portion, and then polished and finished. By doing this, a cylinder 18 having a desired shape with a built-up layer 19 formed with a uniform thickness on the inner surface is obtained.

(Example 1) This Example 1 was carried out according to the steps shown in FIG.

First, a straight center hole 2 is machined in the center of a round bar base material (see Fig. 1 (L)) made of chromium molybdenum steel (JIS SCM) to fabricate the cylinder assembly 3. (see figure (b)), then N i -Co -Cr -S is added inside the center hole 2 of the cylinder assembly 3.
3.5 kg of powder 4 made of i-B type self-fusing alloy
After sealing (see FIG. 1(c)), it was heated to about 1150° C. with both ends closed to create an inert atmosphere inside, and the powder 4 made of a self-fusing alloy inside was melted.

Next, the cylinder assembly 3 is attached to a rotating device and rotated, and the molten self-fusing alloy is solidified by centrifugal casting while being in close contact with the inner surface of the cylinder assembly 3. After cooling, a first sensuous layer with a uniform thickness is formed. 5 (see FIG. 1(d)).

Next, after leaving one end open, insert N into the center hole 2.
Adding NbC to i-Co-Cr-3i-B self-fluxing alloy
2.5 kg of the powder 6 containing 0% by weight was sealed (see Fig. 1 (8)) 1 with both ends closed to create an inert atmosphere inside and heated to about 1150 to 1200°C to form the powder. Body 6 was melted.

Next, the cylinder assembly 3 is attached to a rotating device and rotated, and the molten self-fusing alloy and NbC are solidified by centrifugal casting while being in close contact with the first sensual layer 5, and after cooling, a second layer of uniform thickness is formed. A fleshy layer 7 was formed (Fig. 1(f)
reference).

Next, when the hardness of the first and second build-up layers 5 and 7 and the change in hardness from the surface were investigated, it was found that the first
The results were shown in the table (measured by HRC) and FIG. 2 (measured by Hv).

(Comparative Example 1) Comparative Example 1 was carried out according to the steps shown in FIG.

First, a straight center hole 22 is machined in the center of a round bar base material (see Fig. 5(a)) made of chromium molybdenum steel (JI SSCM) to fabricate the cylinder assembly 23. 5(b)), then Nt-Co-Cr-3i is placed inside the center hole 22 of the cylinder assembly 23.
-3.5 kg of powder 24 made of B-based self-fusing alloy
After sealing (see FIG. 5(C)), it was heated to about 1150° C. with both ends closed to create an inert atmosphere inside, and the powder 24 made of a self-fusing alloy inside was melted.

Next, the cylinder assembly 23 is attached to a rotating device and rotated, and the molten self-fusing alloy is solidified while being in close contact with the inner surface of the cylinder assembly 23 by centrifugal casting, and after cooling, a fleshy layer 25 with a uniform thickness is formed. (See FIG. 5(d)).

Next, the hardness of the flesh-sensitive layer 25 was examined, and the results were also shown in Table 1 (measured by HRC).

(Comparative Example 2) In this Comparative Example 2, the Ni used in Comparative Example 1 was
-Co-Cr-5i -B-based self-fluxing alloy, 5% by weight
Comparative Example 1 except that powder 24 to which NbC was added was used.
The built-up layer 25 was formed in the same manner as above.

Next, the hardness of the built-up layer 25 and the change in hardness from the surface were investigated, and the results were as shown in Table 1 (however, HR
The results were as shown in Figure 3 (measured by Hv) and Figure 3 (measured by Hv).

As shown in FIG. 2, in Example 1 of the present invention, the wear-resistant component (N b C) contained in the second build-up layer 7 is concentrated near the boundary with the first build-up layer 5. , there is a first
Since there is a build-up layer 5 and it is alloyed with the base metal, the hardness from the base metal to the build-up layer is at a high level, and the change in hardness is not very rapid, and
The adhesion was also extremely excellent, and it was confirmed that a highly hard surface could be formed after finishing.

On the other hand, in Comparative Example 1, the hardness is low because it does not contain wear-resistant components, and in Comparative Example 2, as shown in Figure 3, the wear-resistant components are concentrated in the vicinity of the base material, and the hardness is low. It was confirmed that due to the lack of alloying, the hardness from the base metal to the overlay layer changed significantly and rapidly, and the adhesion to the base metal was also poor. .

(Example 2) Example 2 was carried out according to the steps shown in FIG.

A cylinder assembly 13 is formed by machining a center hole 12 with different opening diameters at both ends in the center of a round bar base material 11 (see Fig. 4(a)) made of mass, chromium molybdenum steel (JIS SCM). (see FIG. 4(b)), then open the center hole 1 of the cylinder assembly 13.
Figure 4 (C
), approximately 1150 mm with both ends closed and an inert atmosphere inside. It was heated to 0 to melt the internal powder 14 made of a self-fusing alloy.

Next, the cylinder assembly 13 is attached to a rotating device and rotated, and the molten self-fusing alloy is solidified by centrifugal casting while remaining in close contact with the large diameter side portion of the center hole 12 of the cylinder assembly 13. A built-up layer 15 was formed (Fig. 4(d)
)reference).

Next, after leaving one end open, the center hole 12 is filled with
2.5 kg of granular material 16 made of a self-fusing alloy of N i -Co-Cr-S i -B system is enclosed (see Fig. 4(e)), and both ends are closed to create an inert atmosphere inside. The powder and granular material 16 was melted by heating to about 1150°C.

Subsequently, the cylinder assembly 13 is attached to a rotating device and rotated to solidify the molten self-fluxing alloy while keeping it in close contact with the first build-up layer 15 and the small opening diameter portion of the center hole 12, and after cooling, the self-fusing alloy is solidified. A second overlay layer 17 having a uniform thickness was formed (see FIG. 4(f)).

Next, the second fleshy layer 17 and the first overlay layer 15 are cut to form a center hole 18a having a predetermined shape with a large opening diameter portion and a small opening diameter portion, and then polished and finished. By doing this, a cylinder 18 was obtained in which a build-up layer 19 made of a corrosion-resistant alloy was uniformly formed on the inner surface (No. 4
(See figure (g)).

[Effects of the Invention] As described above, according to the present invention, when producing a cylinder by overlaying a self-fusing alloy on the inner surface of a cylinder by centrifugal casting, the self-fusing alloy is centrifugally cast in multiple steps. By laminating and overlaying on the inner surface of the cylinder, we are able to manufacture cylinders that have not only excellent corrosion resistance, but also have a strong fleshy layer with excellent wear resistance due to high adhesion strength. In addition, it is possible to manufacture cylinders in which a thick fleshy layer is formed, or cylinders in which a built-up layer of uniform thickness is formed on the inner surface of a cylinder that has a concave and/or curved portion or a tapered portion that is not straight. The very good effect that it is possible to achieve is brought about.

[Brief explanation of the drawing]

FIGS. 1(a) to (f) are explanatory diagrams sequentially showing the manufacturing process of a cylinder according to an embodiment of the present invention, and FIG. 2 is an examination of changes in hardness on the inner surface of a cylinder manufactured according to Example 1 of the present invention. FIG. 3 is a graph showing the results of examining the hardness change on the inner surface of the cylinder manufactured according to Comparative Example 2. FIGS. Explanatory diagram showing the manufacturing process of the cylinder sequentially, No. 5
Figures (a) to (d) are explanatory diagrams sequentially showing the manufacturing process of a cylinder according to a conventional example. 1, 11... Round bar base material, 2.12... Center hole, 3.13... Cylinder assembly, 4.14... Powder, s, is,... 1st Sensitive layer, 6.16...Powder material, 7.17...Second overlay layer, 8.18...Cylinder.

Claims (3)

[Claims] (1) When producing a cylinder by overlaying a self-fusing alloy on the inner surface of a cylinder by centrifugal casting, the self-fusing alloy is layered and overlaid on the inner surface of the cylinder in multiple steps each time by centrifugal casting. How to manufacture cylinders. (2) When producing a cylinder by overlaying a self-fusing alloy on the inner surface of the cylinder by centrifugal casting, small amounts of B, Si, etc. are added to the nickel-chromium or cobalt-chromium alloy.
, C, etc. is added to the inner surface of the cylinder by centrifugal casting, and then W, Nb, Ta, V,
A wear-resistant self-fluxing alloy containing one or more wear-resistant components selected from carbides such as Ti and borides such as Cr, Fe, Ni, and Co is further laminated and overlaid on the inner surface of the cylinder by centrifugal casting. Characteristic Claim No. (
1) A method for manufacturing the cylinder described in item 1). (3) When manufacturing cylinders by overlaying self-fusing alloys on the inner surface of cylinders by centrifugal casting, small amounts of B, Si, etc. are added to alloys such as nickel-chromium or cobalt-chromium.
A self-fusing alloy to which alloy components such as , C, etc. are added is deposited on the inner surface of the cylinder by centrifugal casting, and then a self-fusing alloy that is the same as or different from the above-mentioned self-fusing alloy is further laminated and deposited on the inner surface of the cylinder by centrifugal casting. A method for manufacturing a cylinder according to claim (1).