JPH08131713A - Wear-resistant shoe in sewage treeatment machine - Google Patents

Abstract

PURPOSE: To make replacement and exchange of a shoe unnecessary so long as a main body is usable and enable it to be used for a long time by preparing the shoe in such a way that a zirconia ceramic chip with a high breaking toughness value is embedded and fitted monolithically on the sliding face to a rail of a shoe base material. CONSTITUTION: A shoe 4 is constituted of a shoe base body 40 and a zirconia ceramic chip 41 embedded and fitted in the shoe base body 40 and provided on the sliding face to a rail. Fitting flanges 42 and 42 are provided monolithically, if necessary, on both sides of the shoe base body 40 and a ceramic chip 41 is monolithically provided in the shoe base material 40 being thicker than the fitted flange 42 part in such a way that it is exposed on the surface being brought into contact with a rail but it is not projected and on the same level of face. In the ceramic chip 41, the size is defined so as to cover the whole sliding face to the rail and the crosssectional shape is made into a trapezoid so as to make the area of the sliding face side with the rail small and the area of the opposite bucket 3 fixing side large and the chip is embedded and fitted into a monolithical body when the shoe base material 40 is prepd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewage treatment machine such as a sand lifter, a sludge attractor, a flight conveyor, etc., which has excellent corrosion resistance and wear resistance on the rail sliding surface of a shoe that slides on a rail. In a sewage treatment machine in which the ceramic chip of (1) is used, the ceramic chip that is weak against impact is protected from external pressure by being integrally provided on the shoe base material having the required hardness and toughness to improve the corrosion and wear of the shoe. It relates to a wear resistant shoe.

[0002]

2. Description of the Related Art In the sewage treatment process, a large amount of sand particles are mixed in a treatment tank provided with a sand lifter, a flight conveyor, a sludge attractor, etc. located relatively in the first half. The buckets of sand lifters, flight conveyors, flights of sludge scrapers, etc. slide and move while supporting the load on rails laid along the longitudinal direction of the pond and pulling up and scraping sludge. Work such as frying. However, when this bucket, flight, etc. slides on the rail, sliding friction due to mixed sand and the like is severe. Therefore, to prevent the buckets, flights, etc. from being directly worn, a shoe is replaceably attached to the sliding part that comes into contact with the rails, and if this shoe wears to the allowable limit, replace it with a new shoe to improve the wear resistance of the bucket, flights, etc. I am trying to. The material used for this shoe is ordinary cast iron (FC20) to spheroidal graphite cast iron (FCD) with good wear resistance.
Up to 60) are commonly used. Further, use of SUS304, synthetic resin or the like has been proposed for corrosion, deterioration and wear.

[0003]

However, in sewage containing chlorine ions, sulfate ions, sand, etc., the shoes of ordinary cast iron have insufficient corrosion resistance and wear resistance, and the shoes are often subjected to severe wear and corrosion. It needs to be replaced, and replacement of this shoe requires a considerable amount of work. It is also possible to use ceramics for the entire shoe as an improvement against corrosion deterioration, but the fracture toughness value becomes low and it becomes fragile, so it is weak against impact and unusable. Further, when used under severe operating conditions in which a large amount of sand enters the sliding surface, ordinary ceramics lack wear resistance.

The present invention is used under such severe conditions,
The purpose of the present invention is to provide a long-life shoe that does not require replacement and replacement of the shoe during the usable period of the main body of the sand treatment machine such as a sand lifter and a sludge scraper.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and a shoe used in a sewage treatment machine has a zirconia-based ceramic chip having a high fracture toughness value on a sliding surface with a rail. The gist of the present invention is that it is manufactured by fitting it integrally with a shoe base material for protecting it from impact external pressure.

[0006]

[Operation] A shoe with a zirconia-based ceramic chip with a high fracture toughness value is used as a shoe that is installed on the sliding part of the bucket of a sand lifter, the flight of a sludge attractor, etc., and a metal with the required strength and toughness. Since it is fitted or embedded in a cast shoe base material to be integrated, this ceramic chip achieves the desired corrosion resistance and wear resistance, and the base material into which this chip is fitted and embedded is subjected to external pressure such as impact. Protects the tip from scratches, a shoe with excellent corrosion resistance and wear resistance that covers the brittleness of ceramics can be obtained and the life of the shoe can be extended, and the shoe can be replaced until the usable period of the sewage treatment machine body. Can be eliminated.

[0007]

The wear resistant shoes in a sewage treatment machine such as a sand lifter and a sludge attractor according to the present invention will be described below with reference to the illustrated embodiments. The embodiment shown in FIGS. 6 to 7 is a sand lifter A,
As shown in FIGS. 6 and 7, a sand blaster chain 2 is stretched endlessly in the water tank 1 along the water surface in the longitudinal direction, and buckets 3 are laid in this chain at required intervals.
Is attached, the bucket 3 is moved along the bottom, and the dirty sand that has settled at the bottom is taken out, scraped and discharged. Then, in the sand lifter A, the shoes 4 are attached to the sliding surface with the rails to prevent the buckets from being worn when the buckets 3 slide and move on the rails 5 laid on the bottom surface of the water tank.

The shoe 4 can have various shapes as shown in FIGS. The shoe 4 is composed of a shoe mother body 40 and a ceramic chip 41 embedded in the shoe mother body and provided on the sliding surface of the rail 5. The shoe base 40 has a required size and shape suitable for mounting on the bucket 3, and the material thereof is the same as that of the conventional one, such as ordinary cast iron to spheroidal graphite, or stainless steel. Hv500
It is made of metal casting to some extent.

If necessary, mounting flanges 42, 42 are integrally provided on both sides of the shoe base body 40. The shoe base material 40 is thicker than the mounting flange portion and is exposed at the contact surface with the rail. However, the ceramic chip 41 is integrally provided so as to be flush so as not to project. The size of this ceramic chip 41 is determined so as to cover the entire surface that slides on the rail, and the cross-sectional shape has a small area on the sliding surface side with the rail as shown in FIG. The shoe base material 40 is formed into a trapezoidal shape having a large area on the mounting side, and when the shoe base material 40 is manufactured, it is embedded or fitted to be integrated. In this case, one ceramic chip 41 is provided for one shoe base material 40 as shown in FIGS. Alternatively, there is a case where it is manufactured by dividing it into three or more parts and then fitted and fixed. When two ceramic chips 41 are used, they are arranged in parallel, but when three or more are used, they may be arranged in a zigzag pattern or in an array as shown in FIGS. The method of arranging the plurality of ceramic chips 41 is not limited to this, and various methods can be considered.

The ceramic chip 41 is manufactured separately from the shoe base material 40 and has a trapezoidal cross section, and is fitted and fixed in the ceramic chip fitting groove 43 formed in the shoe base material 40.

Also shown in FIG. 5 are shoes 6 attached to the lower end of the flight, which is provided in a chain of the sand scraper at a required interval, and scrapes sludge deposited on the bottom of the waterway to the sludge hopper by flight. Try to get closer. The shape of the shoe base material 60 of the shoe 6 attached to this flight is determined according to the shape of the flight, and the shoe base material 60 is fitted into the ceramic chip 61 in the same manner as the embodiment shown in FIGS. Combined into one.

Zirconia and silicon nitride are suitable as the ceramic. The zirconia may use a usual stabilizer. Table 1 shows the physical properties of the shoe and the wear resistance when various ceramics are attached to the sliding surface.

[0013]

[Table 1]

Although high-level silicon carbide shows a surface wear performance equal to or higher than that of zirconia, in a machine such as the one used in the present invention, a lack of toughness is likely to cause minute chipping. Furthermore, the wear resistance of alumina is slightly better than that of FCD material, which is a conventional material used under the usage conditions such as sand entrapment and impact, but zirconia has a wear resistance of 10 times or more. Sex is recognized. Therefore, overall, zirconia is most suitable.

As for the function of the shoe base material, a load is hardly applied to the shoe because it is received by the shoe, but a certain degree of abrasion resistance is required in view of the nature of movement in sand. That is, if it is too soft, the chip will be exposed and the corner will be chipped.
In order to prevent this, a metal casting having a hardness of about ⅓ of the chip hardness is heat treated, that is, a hardness of about Hv500 is sticky, and an appropriate hardness that is difficult to crack is obtained. There is an advantage that the hole for inserting the chip is made by casting.

It is important for ceramics as wear resistant materials to have an appropriate balance of strength, hardness, and toughness values according to the conditions of use, and hard materials are not necessarily good, and sand is not suitable for water treatment machines. It has been found that zirconia is excellent as a wear-resistant sliding material in a sliding portion in which the presence of the And hardness of base material, Hv500
The hardness of the ceramic chip is about 3 times that of the base metal.

[0017]

[Formula 1]

It is suitable to use zirconia having a degree of toughness.

[0019]

The wear-resistant shoe of the sewage treatment machine according to the present invention is integrally formed by embedding the shoe with a zirconia-based ceramic chip having a high fracture toughness value in the shoe base material on the sliding surface with the rail. Since it is built and manufactured, it is protected by the shoe base material against impact external pressure applied to the shoe, and the wear with the rail is supported by the ceramic chip, and it is dirty as a shoe with excellent wear resistance and corrosion resistance. During the usable period of the sand processing machine main body, there is an advantage that it does not require replacement and replacement of shoes and can be used for a long time. Since the base metal of the shoe is made of a metal casting with a hardness of about Hv500, it supports impact external pressure applied to the shoe and protects the ceramic chip with appropriate abrasion resistance in the sliding portion where sand is present. There is an advantage that can be. As a shoe with excellent wear resistance and corrosion resistance, the shoe base material is a metal casting with a hardness of about Hv500, and the ceramic chip has a hardness about 3 times that of the base material and a predetermined toughness. There is an advantage that it is not necessary to replace and replace the shoe during the usable period of the main body of the sand treatment machine.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment in which a shoe of the sewage treatment machine of the present invention is attached to a bucket of a sand lifter.

2A and 2B show a first embodiment of the shoe, FIG. 2A is a plan view, FIG. 2B is a vertical sectional front view, and FIG.

FIG. 3 shows a different second embodiment, (a) is a plan view,
(B) is a vertical sectional front view, and (c) is a side view of the same.

FIG. 4 shows a different third embodiment, (a) is a plan view,
(B) is a vertical sectional front view, and (c) is a side view of the same.

FIG. 5 shows an embodiment of the flight shoe of the present invention,
(A) is a plan view, (b) is a vertical sectional front view, and (c) is a side view thereof.

FIG. 6 is a front view showing an embodiment of a sand blasting machine.

FIG. 7 is a vertical sectional view of the same.

[Explanation of symbols]

 1 Channel 2 Chain 3 Bucket 4 Shoe 40 Shoe Base Material 41 Ceramic Chip 5 Rail 6 Flight 7 Shoe 70 Shoe Base Material 71 Ceramic Chip A Sand Lifter

Claims (3)

[Claims] 1. A shoe used for a sewage treatment machine such as a sand lifter and a sludge attractor for protecting a zirconia-based ceramic chip having a high fracture toughness value on a sliding surface with a rail from an impact external pressure. A wear-resistant shoe for a sewage treatment machine, which is manufactured by being embedded in a base material and integrally provided. 2. A wear-resistant shoe for a sewage treatment machine according to claim 1, wherein the shoe base material is a metal casting having a hardness of about Hv500. 3. The shoe base material is a metal casting having a hardness of about Hv500, and the tip has a hardness about three times that of the base material, and The wear resistant shoe for a sewage treatment machine according to claim 1, wherein the shoe has a fracture toughness of a certain degree.