High wear-resistant mixing pelletizing machine liner and preparation method thereof

Abstract

The present invention belongs to the technical field of liners, and specifically discloses a high-wear-resistant mixed pelletizing machine liner and a preparation method thereof. The liner includes a base layer and a wear-resistant layer composited on the surface of the base layer. The base layer is made of high-strength alloy steel material, and its chemical composition is calculated by mass percentage as follows: C: 0.25-0.35%, Si: 0.4-0.8%, Mn: 1.2-1.6%, Cr: 0.8-1.2%, Mo: 0.2-0.4%, Ni: 0.3-0.6%, Nb: 1.0-1.6%, and the balance is Fe; the wear-resistant layer includes tungsten carbide particles, a composite alloy material, and an adhesive. The present invention adopts the above-mentioned high-wear-resistant mixed pelletizing machine liner and a preparation method thereof, aiming to solve the problems of insufficient wear resistance and short service life of existing mixed pelletizing machine liners, and improve the comprehensive performance of the mixed pelletizing machine liner through composite structure design and special preparation process.

Description

Technical Field

[0001] The invention relates to the technical field of lining plates, in particular to a lining plate for a high-wear-resistant mixing pelletizing machine and a preparation method thereof. Background Art

[0002] A mixing pelletizer is a device that mechanically agglomerates fine-grained materials into spherical particles (pellets) under specific conditions. It pelletizes fine powder materials to improve their flowability and transportability. This provides regular-shaped, high-strength raw materials for subsequent processes such as sintering and roasting, improving production efficiency and product quality. An appropriate amount of water or binder is sprayed into the material to impart a certain degree of moisture and viscosity. Using a rotating disc or drum, centrifugal force and friction cause the material to continuously roll and gradually agglomerate into spherical particles. Qualified pellets are separated using a screen or sorting device, while unqualified material is returned for reprocessing.

[0003] The pelletizer liner is a protective layer installed on the inner wall of the pelletizer, typically made of wear-resistant material. It prevents fine particles and aqueous solutions from directly contacting the pelletizer barrel or discs, extending equipment life. Through appropriate surface design (such as texture and roughness), it improves the rolling properties of the material and promotes pellet formation, reducing the need for frequent maintenance and component replacement due to wear.

[0004] In industries like iron and steel, pelletizing machines are essential equipment for preparing ore pellets. During the pelletizing process, the liner, a key component of the machine, comes into direct contact with the material, subjecting it to intense impact, friction, and chemical corrosion. With the expansion of production scale and improvements in efficiency, the demands on the pelletizer's operating intensity and operating time are increasing, leading to increasingly severe liner wear.

[0005] Traditional pelletizing machine liners lack wear resistance and have a short service life. Frequent liner replacement not only increases equipment maintenance costs but also causes production interruptions, impacting productivity. Furthermore, the manufacturing process for some existing liners is complex and expensive, making them unsuitable for large-scale application. Therefore, developing a highly wear-resistant, yet simple and cost-effective hybrid pelletizing machine liner is of great practical significance. Summary of the Invention

[0006] The purpose of the present invention is to provide a highly wear-resistant mixing pelletizing machine liner and a preparation method thereof, aiming to solve the problems of insufficient wear resistance and short service life of the existing mixing pelletizing machine liner, and to improve the comprehensive performance of the mixing pelletizing machine liner through composite structure design and special preparation process.

[0007] To achieve the above-mentioned purpose, the present invention provides a high-wear-resistant mixed pelletizing machine lining, comprising a base layer and a wear-resistant layer composited on the surface of the base layer, wherein the base layer is made of high-strength alloy steel material, and its chemical composition is as follows by mass percentage: C: 0.25-0.35%, Si: 0.4-0.8%, Mn: 1.2-1.6%, Cr: 0.8-1.2%, Mo: 0.2-0.4%, Ni: 0.3-0.6%, Nb: 1.0-1.6%, and the balance is Fe; the wear-resistant layer comprises tungsten carbide particles, a composite alloy material, and an adhesive, and the chemical composition of the composite alloy material is as follows by mass percentage: Cr: 15-20%, Mo: 5-8%, W: 3-5%, C: 0.1-0.2%, Y: 1.2-2.0%, and the balance is Ni.

[0008] Preferably, the volume fraction of the tungsten carbide particles is 30-40%, and the particle size range is between 50-150 μm.

[0009] Preferably, the chemical components in the composite alloy material are all powders with a purity of ≧99% and a particle size of 0.5-1.5 μm.

[0010] Preferably, the adhesive is turpentine.

[0011] The preparation method of a high wear-resistant mixing pelletizing machine liner comprises the following steps:

[0012] Step 1: Preparation of the base layer: Accurately weigh the raw materials of each chemical component, add the weighed raw materials of the chemical component into a vacuum induction melting furnace for melting. During the melting process, control the melting temperature and stir them thoroughly to ensure uniform distribution of the alloy components. Cast the melted alloy liquid into a pre-designed mold, take cooling measures, and heat treat the cast base layer;

[0013] Step 2: Preparation of composite alloy material: According to the chemical composition requirements of the composite alloy material, the various chemical components are mixed to form an alloy mixture, and then the alloy mixture is ground under the protection of nitrogen at a grinding speed of 300 rpm for 2 hours. The alloy mixture is taken out, and then the alloy mixture is mixed and stirred evenly with a binder to form an alloy composite. The alloy composite is then heated and melted under vacuum conditions for 2 hours to obtain a composite alloy material.

[0014] Step three, preparation of the wear-resistant layer, mixing the tungsten carbide particles and the composite alloy material evenly, and using a thermal spraying process to spray the mixture of tungsten carbide particles and the composite alloy material onto the surface of the base layer, so that the tungsten carbide particles are evenly embedded in the composite alloy material coating to form a wear-resistant layer, and thus a mixed pelletizing machine liner is obtained.

[0015] Preferably, in step three, the tungsten carbide particles need to be pretreated before being mixed with the composite alloy material. The specific operation of the pretreatment is: cleaning the tungsten carbide particles, and then drying the cleaned tungsten carbide particles in an oven at 100-150°C for 2-3 hours to make its moisture content less than 0.1%, and performing surface activation treatment on the dried tungsten carbide particles. A nickel layer with a thickness of 1-3 μm is plated on the surface of the tungsten carbide particles by a chemical nickel plating method to improve the bonding strength between the tungsten carbide particles and the nickel-based alloy.

[0016] Preferably, in step three, during the thermal spraying process, the distance between the spray gun and the surface of the base layer is controlled to be 150-200 mm, and the spraying speed is 5-8 m / s.

[0017] Preferably, in step three, the spraying thickness of the wear-resistant layer is 5-12 mm.

[0018] The advantages and beneficial effects of the present invention using the above-mentioned high wear-resistant mixing pelletizing machine liner and the preparation method thereof are:

[0019] 1. The wear-resistant layer of the present invention contains a large amount of tungsten carbide particles. The tungsten carbide particles have extremely high hardness and wear resistance, can effectively resist the wear of materials and grinding media, and greatly improve the wear resistance of the liner.

[0020] 2. The base layer of this invention is made of high-strength alloy steel, which has excellent toughness and strength. It can withstand the impact loads during machine operation and prevent the liner from cracking under impact. At the same time, the wear-resistant layer and the base layer are firmly metallurgically bonded through a thermal spraying process. When the composite liner is impacted, the impact force can be effectively transferred to the base layer, preventing the wear-resistant layer from falling off and ensuring the overall impact resistance of the liner.

[0021] 3. The composite lining of the present invention has high wear resistance and good impact resistance, and its service life is significantly extended. Under the same working conditions, the service life of the composite lining of the present invention is 2-3 times that of the traditional rubber lining, which reduces the number of lining replacements, reduces equipment maintenance costs, and improves production efficiency.

[0022] The technical solution of the present invention is further described in detail below through examples. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is further illustrated by the following examples.

[0024] Unless otherwise defined, technical or scientific terms used in the present invention shall have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

[0025] Unless otherwise defined, the reagents, equipment and other materials used in the present invention are all commercially available.

[0026] Example 1

[0027] A high-wear-resistant mixed pelletizing machine lining comprises a base layer and a wear-resistant layer composited on the surface of the base layer. The base layer is made of high-strength alloy steel material, and its chemical composition is as follows by mass percentage: C: 0.25%, Si: 0.8%, Mn: 1.4%, Cr: 0.8%, Mo: 0.3%, Ni: 0.5%, Nb: 1.2%, and the balance is Fe; the wear-resistant layer comprises tungsten carbide particles, a composite alloy material, and an adhesive. The chemical composition of the composite alloy material is as follows by mass percentage: Cr: 15%, Mo: 5%, W: 4%, C: 0.1%, Y: 1.3%, and the balance is Ni.

[0028] The volume fraction of the tungsten carbide particles is 32%, and the particle size thereof is 80 μm.

[0029] The chemical components in the composite alloy material are all powders with a purity of ≥99% and a particle size of 0.8 μm.

[0030] The adhesive is turpentine.

[0031] The preparation method of a high wear-resistant mixing pelletizing machine liner comprises the following steps:

[0032] Step 1: Prepare the base layer. Accurately weigh the raw materials of each chemical component and add them into a vacuum induction melting furnace for melting. During the melting process, control the melting temperature and stir them thoroughly to ensure that the alloy components are evenly distributed. Cast the melted alloy liquid into a pre-designed mold, take cooling measures, and heat treat the base layer after casting.

[0033] Step 2: Preparation of composite alloy materials. According to the chemical composition requirements of the composite alloy materials, the various chemical components are mixed to form an alloy mixture. Then, under the protection of nitrogen, the alloy mixture is ground at a speed of 300 rpm for 2 hours. The alloy mixture is taken out, and then the alloy mixture and the binder are mixed and stirred evenly to form an alloy composite. The alloy composite is then heated and melted under vacuum conditions for 2 hours to obtain a composite alloy material.

[0034] Step 3: Preparation of wear-resistant layer: clean the tungsten carbide particles, and then dry the cleaned tungsten carbide particles in an oven at 120°C for 2 hours to make its moisture content less than 0.1%. The dried tungsten carbide particles are surface activated and a 2μm thick nickel layer is plated on the surface of the tungsten carbide particles by chemical nickel plating to improve the bonding strength between the tungsten carbide particles and the nickel-based alloy.

[0035] The tungsten carbide particles and the composite alloy material are mixed evenly, and the mixture of the tungsten carbide particles and the composite alloy material is sprayed onto the surface of the base layer using a thermal spraying process, so that the tungsten carbide particles are evenly embedded in the composite alloy material coating. During the thermal spraying process, the distance between the spray gun and the base surface is controlled at 180 mm, and the spraying speed is 6 m / s to form an 8 mm wear-resistant layer to obtain a mixed pelletizing machine liner.

[0036] Example 2

[0037] A high-wear-resistant mixed pelletizing machine lining comprises a base layer and a wear-resistant layer composited on the surface of the base layer. The base layer is made of high-strength alloy steel material, and its chemical composition is as follows by mass percentage: C: 0.30%, Si: 0.4%, Mn: 1.6%, Cr: 1.0%, Mo: 0.2%, Ni: 0.6%, Nb: 1.5%, and the balance is Fe; the wear-resistant layer comprises tungsten carbide particles, a composite alloy material, and an adhesive. The chemical composition of the composite alloy material is as follows by mass percentage: Cr: 18%, Mo: 8%, W: 3%, C: 0.15%, Y: 1.5%, and the balance is Ni.

[0038] The volume fraction of the tungsten carbide particles is 38%, and the particle size thereof is 100 μm.

[0039] The chemical components in the composite alloy material are all powders with a purity of ≥99% and a particle size of 1.0 μm.

[0040] The adhesive is turpentine.

[0041] The preparation method of a high wear-resistant mixing pelletizing machine liner comprises the following steps:

[0042] Step 1: Prepare the base layer. Accurately weigh the raw materials of each chemical component and add them into a vacuum induction melting furnace for melting. During the melting process, control the melting temperature and stir them thoroughly to ensure that the alloy components are evenly distributed. Cast the melted alloy liquid into a pre-designed mold, take cooling measures, and heat treat the base layer after casting.

[0043] Step 2: Preparation of composite alloy materials. According to the chemical composition requirements of the composite alloy materials, the various chemical components are mixed to form an alloy mixture. Then, under the protection of nitrogen, the alloy mixture is ground at a speed of 300 rpm for 2 hours. The alloy mixture is taken out, and then the alloy mixture and the binder are mixed and stirred evenly to form an alloy composite. The alloy composite is then heated and melted under vacuum conditions for 2 hours to obtain a composite alloy material.

[0044] Step 3: Preparation of wear-resistant layer: clean the tungsten carbide particles, and then dry the cleaned tungsten carbide particles in an oven at 110°C for 2.5 hours to make its moisture content less than 0.1%. Perform surface activation treatment on the dried tungsten carbide particles, and use chemical nickel plating to plate a 3μm thick nickel layer on the surface of the tungsten carbide particles to improve the bonding strength between the tungsten carbide particles and the nickel-based alloy.

[0045] The tungsten carbide particles and the composite alloy material are mixed evenly, and the mixture of the tungsten carbide particles and the composite alloy material is sprayed onto the surface of the base layer using a thermal spraying process, so that the tungsten carbide particles are evenly embedded in the composite alloy material coating. During the thermal spraying process, the distance between the spray gun and the base surface is controlled at 150 mm, and the spraying speed is 5 m / s to form a 6 mm wear-resistant layer to obtain a mixed pelletizing machine liner.

[0046] Example 3

[0047] A high-wear-resistant mixed pelletizing machine lining comprises a base layer and a wear-resistant layer composited on the surface of the base layer. The base layer is made of high-strength alloy steel material, and its chemical composition is as follows by mass percentage: C: 0.35%, Si: 0.7%, Mn: 1.5%, Cr: 1.2%, Mo: 0.4%, Ni: 0.6%, Nb: 1.6%, and the balance is Fe; the wear-resistant layer comprises tungsten carbide particles, a composite alloy material, and an adhesive. The chemical composition of the composite alloy material is as follows by mass percentage: Cr: 18%, Mo: 8%, W: 5%, C: 0.2%, Y: 1.8%, and the balance is Ni.

[0048] The volume fraction of the tungsten carbide particles is 40%, and the particle size thereof is 60 μm.

[0049] The chemical components in the composite alloy material are all powders with a purity of ≥99% and a particle size of 1.2 μm.

[0050] The adhesive is turpentine.

[0051] The preparation method of a high wear-resistant mixing pelletizing machine liner comprises the following steps:

[0052] Step 1: Prepare the base layer. Accurately weigh the raw materials of each chemical component and add them into a vacuum induction melting furnace for melting. During the melting process, control the melting temperature and stir them thoroughly to ensure that the alloy components are evenly distributed. Cast the melted alloy liquid into a pre-designed mold, take cooling measures, and heat treat the base layer after casting.

[0053] Step 2: Preparation of composite alloy materials. According to the chemical composition requirements of the composite alloy materials, the various chemical components are mixed to form an alloy mixture. Then, under the protection of nitrogen, the alloy mixture is ground at a speed of 300 rpm for 2 hours. The alloy mixture is taken out, and then the alloy mixture and the binder are mixed and stirred evenly to form an alloy composite. The alloy composite is then heated and melted under vacuum conditions for 2 hours to obtain a composite alloy material.

[0054] Step 3: Preparation of wear-resistant layer: clean the tungsten carbide particles, and then dry the cleaned tungsten carbide particles in an oven at 130°C for 3 hours to reduce the moisture content to less than 0.1%. Perform surface activation treatment on the dried tungsten carbide particles, and plate a 1 μm thick nickel layer on the surface of the tungsten carbide particles by chemical nickel plating to improve the bonding strength between the tungsten carbide particles and the nickel-based alloy.

[0055] The tungsten carbide particles and the composite alloy material are mixed evenly, and the mixture of the tungsten carbide particles and the composite alloy material is sprayed onto the surface of the base layer using a thermal spraying process, so that the tungsten carbide particles are evenly embedded in the composite alloy material coating. During the thermal spraying process, the distance between the spray gun and the base surface is controlled at 200 mm, and the spraying speed is 8 m / s to form a 10 mm wear-resistant layer to obtain a mixed pelletizing machine liner.

[0056] Table 1 lists the hardness, weight loss from wear and service life of the mixing pelletizing machine liner of Examples 1-3.

[0057] Table 1 Performance test results of liner of mixing pelletizing machine

[0058] Group <![CDATA[Average hardness (HV 0.2 )]]> Weight loss due to wear (mg) Service life (months) Example 1 812 2.1 16 Example 2 798 1.9 18 Example 3 789 2.2 17

[0059] Therefore, the present invention adopts the above-mentioned high wear-resistant mixing pelletizing machine lining and its preparation method, aiming to solve the problems of insufficient wear resistance and short service life of the existing mixing pelletizing machine lining, and improves the comprehensive performance of the mixing pelletizing machine lining through composite structure design and special preparation process.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. High wear-resistant mixing pelletizing machine liner, characterized by: The invention comprises a base layer and a wear-resistant layer composited on the surface of the base layer, wherein the base layer is made of high-strength alloy steel material, and its chemical composition is calculated by mass percentage as follows: C: 0.25-0.35%, Si: 0.4-0.8%, Mn: 1.2-1.6%, Cr: 0.8-1.2%, Mo: 0.2-0.4%, Ni: 0.3-0.6%, Nb: 1.0-1.6%, and the balance is Fe; the wear-resistant layer comprises tungsten carbide particles and a composite alloy material, and the chemical composition of the composite alloy material is calculated by mass percentage as follows: Cr: 15-20%, Mo: 5-8%, W: 3-5%, C: 0.1-0.2%, Y: 1.2-2.0%, and the balance is Ni; the volume fraction of the tungsten carbide particles is 30-40%; The preparation method of the high wear-resistant mixing pelletizing machine liner comprises the following steps: Step 1: Preparation of the base layer: Accurately weigh the raw materials of each chemical component, add the weighed raw materials of the chemical component into a vacuum induction melting furnace for melting. During the melting process, control the melting temperature and stir them thoroughly to ensure uniform distribution of the alloy components. Cast the melted alloy liquid into a pre-designed mold, take cooling measures, and heat treat the cast base layer; Step 2: preparing a composite alloy material, mixing the various chemical components according to the chemical composition requirements of the composite alloy material to form an alloy mixture, then grinding the alloy mixture under nitrogen at a grinding speed of 300 rpm for 2 hours, taking out the alloy mixture, and then mixing the alloy mixture with a binder to form an alloy composite, and then heating and smelting the alloy composite under vacuum conditions for 2 hours to obtain a composite alloy material; the binder is turpentine; Step 3: Preparation of wear-resistant layer: Mix tungsten carbide particles and composite alloy material evenly, and use thermal spraying process to spray the mixture of tungsten carbide particles and composite alloy material onto the surface of the base layer, so that the tungsten carbide particles are evenly embedded in the composite alloy material coating to form a wear-resistant layer, thus obtaining a mixed pelletizing machine liner; Tungsten carbide particles need to be pretreated before being mixed with composite alloy materials. The specific operations of the pretreatment are: cleaning the tungsten carbide particles, then drying the cleaned tungsten carbide particles in an oven at 100-150°C for 2-3 hours to make its moisture content less than 0.1%, performing surface activation treatment on the dried tungsten carbide particles, and then using the chemical nickel plating method to plate a nickel layer with a thickness of 1-3μm on the surface of the tungsten carbide particles.

2. The high wear-resistant mixing pelletizing machine liner according to claim 1, characterized in that: The particle size of the tungsten carbide particles ranges from 50 to 150 μm.

3. The high wear-resistant mixing pelletizing machine liner according to claim 1, characterized in that: The chemical components in the composite alloy material are all powders with a purity of ≥99% and a particle size of 0.5-1.5 μm.

4. The high wear-resistant mixing pelletizing machine liner according to claim 1, characterized in that: In step 3, during the thermal spraying process, the distance between the spray gun and the substrate surface is controlled at 150-200 mm, and the spraying speed is 5-8 m / s.

5. The high wear-resistant mixing pelletizing machine liner according to claim 1, characterized in that: In step 3, the spraying thickness of the wear-resistant layer is 5-12 mm.