Preparation method for eliminating magnetism of feeding roller of silage maize harvester and feeding roller of silage maize harvester

Abstract

The invention relates to the technical field of welding demagnetization, in particular to a preparation method for eliminating magnetism of a feeding roller of a silage maize harvester and the feeding roller of the silage maize harvester. Comprising the following steps that austenitic stainless steel is adopted for preparing a silage maize harvester feeding roller; welding the base material by adopting a welding wire to form the feeding roller of the silage maize harvester; carrying out vacuum high-temperature solution treatment on the feeding roller of the silage harvester; and pickling and passivating the feeding roller of the silage harvester. The austenitic stainless steel of which the internal structure does not contain ferrite and martensite is selected as a base material to prepare the feeding roller of the silage maize harvester, so that the magnetism of the feeding roller is low, and meanwhile, the mechanical strength requirement of the feeding roller during operation and use is met; demagnetization treatment is carried out through vacuum high-temperature solution treatment after welding, so that magnetism is further reduced; through the combination of all the steps, magnetism generation is controlled to be demagnetized, the silage maize harvester feeding roller meeting the requirement is manufactured, it is guaranteed that a metal detector can achieve the metal detection function, and metal with different strong and weak magnetism can be recognized.

Description

Technical Field

[0001] The invention relates to the technical field of welding demagnetization, in particular to a preparation method for eliminating magnetism of a silage machine feeding roller and a silage machine feeding roller. Background Art

[0002] A silage machine is an agricultural machine that is mainly used to cut, compact and ferment fresh crops (such as corn, sorghum, forage, etc.) to make silage. Silage is a fermented feed that can be stored for a long time and provide nutrition for livestock.

[0003] The feeding module of the silage machine is responsible for feeding and conveying materials during the operation process. It determines the operation quality and efficiency of the entire machine and is the key core part of the entire machine. The feeding module consists of 4 feeding rollers, namely the front upper roller, the front lower roller, the rear upper roller and the rear lower roller. In order to prevent iron objects from mixing into the material during the feeding process and causing destructive damage to the shredding module of the machine, a metal detector is usually installed on the front lower roller, such as Figure 1 The metal detector is used to detect metal objects such as iron wire and round steel mixed in the materials entering between the front upper roller and the front lower roller, and it must be able to identify metals with different magnetic strengths, such as Figure 2 As shown. Once such metal objects enter the feeding module, the metal detector will immediately alarm and shut down. In order to achieve this function, the magnetism of the front upper roller and the front lower roller needs to be as small as possible or even non-magnetic, otherwise the metal detector cannot achieve the detection and shutdown functions.

[0004] At present, in the existing technology, the magnetism of the feed roller weld is too large, and a small amount of ferrite structure appears in the weld, making the silage machine feed roller highly magnetic. Therefore, the silage machine feed roller produced by the existing process cannot meet the normal operation requirements of the metal detection system, and cannot identify metals with different magnetic strengths, resulting in various metal objects with different magnetic strengths entering the body during the operation of the silage machine, causing varying degrees of damage to the cutting module, seriously affecting the quality and service life of the silage machine shredding module and even the entire silage machine equipment. In view of this, it is necessary to provide a process to minimize the magnetism of the silage machine feed roller weld, or even to achieve the requirement of eliminating magnetism. Summary of the invention

[0005] In order to solve the above technical problems existing in the prior art, the present invention provides a preparation method for eliminating the magnetism of a silage machine feeding roller and a silage machine feeding roller.

[0006] The technical solution of the present invention to solve the above technical problems is as follows:

[0007] The first aspect of the present invention is to provide a preparation method for eliminating the magnetism of a silage machine feeding roller, comprising the following steps:

[0008] (1) Austenitic stainless steel is used to prepare the silage machine feed roller;

[0009] (2) welding the base material with welding wire to form a silage machine feed roller;

[0010] (3) vacuum high temperature solution treatment of the silage machine feed roller;

[0011] (4) The silage machine feed roller is pickled and passivated.

[0012] According to the preparation method for eliminating magnetism of a silage machine feed roller provided by the present invention, firstly, austenitic stainless steel whose internal structure does not contain ferrite and martensite is selected as the base material to prepare the silage machine feed roller, so that the magnetism of the feed roller is low and the mechanical strength requirements of the feed roller during operation and use are met; after welding, demagnetization treatment is performed through vacuum high-temperature solution treatment to further reduce magnetism; through the combination of various steps, from controlling the generation of magnetism to demagnetizing magnetism, a silage machine feed roller that meets the requirements is obtained, ensuring that the metal detector can realize the metal detection function and can identify metals with different magnetic strengths.

[0013] On the basis of the above technical solution, the present invention can also make the following improvements:

[0014] Furthermore, the austenitic stainless steel is 316L stainless steel.

[0015] The beneficial effect of adopting the above further technical solution is that 316L stainless steel has a higher chromium and nickel content, wherein the balance between ferrite forming elements (chromium equivalent elements) and austenite forming elements (nickel equivalent elements) determines the amount of ferrite in austenite. By selecting 316L stainless steel as the feed roller steel, a higher percentage of nickel contributes to the formation of austenite, resulting in low magnetism, small magnetism after welding, and good oxidation resistance and corrosion resistance.

[0016] Furthermore, the welding wire is ER316.

[0017] The beneficial effect of adopting the above further technical solution is: selecting welding wire ER316 whose chemical composition matches the base material, while meeting the strength requirements, ensuring that the weld structure is consistent with the base material, reducing the formation of ferrite, and thus reducing the generation of magnetism.

[0018] Furthermore, in step (2), the welding atmosphere is a mixed gas consisting of 98% Ar and 2% CO2 by volume.

[0019] The beneficial effects of adopting the above-mentioned further technical solution are: the argon gas in the welding atmosphere has a good protective effect, so that the weld is well formed, thereby obtaining a high-quality weld; the addition of 2% volume fraction of CO2 reduces the surface tension of the stainless steel droplets and the molten pool, making the weld beautiful.

[0020] Furthermore, in step (3), the vacuum high temperature solution treatment includes a first heating stage, a second heating stage and a third heating stage; the first heating stage is from room temperature to 600°C, the second heating stage is 600-800°C, and the third heating stage is 800-1100°C.

[0021] Furthermore, the heating time of the first heating stage, the second heating stage and the third heating stage are all 1-2 hours, and the insulation time of the silage machine feeding roller at 600°C, 800°C and 1100°C are all 0.5-1 hour.

[0022] The beneficial effect of adopting the above-mentioned further technical solution is that: by heating the stainless steel in stages, the workpiece is heated evenly, the workpiece is kept warm at 600°C, 800°C and 1100°C respectively, the residual ferrite is converted into austenite, the internal inclusions of the stainless steel structure are eliminated, and the mechanical properties of the product are improved; at the same time, the vacuum state can avoid oxidation of the stainless steel surface and ensure the appearance.

[0023] The vacuum high-temperature solution treatment is carried out by placing the silage machine feed roller in a vacuum gas quenching furnace. After the insulation is completed, nitrogen is passed through the furnace for rapid cooling. The cooling time is 90-120 minutes, until the temperature of the product drops below 100°C and then it is taken out of the furnace.

[0024] Furthermore, in step (4), the pickling and passivation treatment includes the following steps: soaking the silage machine feed roller in a mixed pickling solution for 2-4 hours, then rinsing the silage machine feed roller with clean water, and finally drying; the mixed pickling solution is a mixed solution of 80% H2O and 20% H2C2O4 by volume.

[0025] The beneficial effect of adopting the above further technical solution is that: since a thin and dense oxide film is formed on the surface of 316L stainless steel after laser cutting and welding, by using a mixed pickling solution of 80% H2O+20% H2C2O4 (oxalic acid) to pickle and passivate the stainless steel feed roller after high-temperature demagnetization, most of the metal oxides, rust and other impurities on the surface of the stainless steel can be removed, thereby improving the surface corrosion resistance; the treatment time is preferably 3 hours, and the solution temperature is maintained at 25°C.

[0026] Furthermore, in step (2), the welding tooling and parts in contact with the substrate during welding are all made of austenitic stainless steel; in step (3), the silage machine feed roller is placed in a heating tooling, and then the heating tooling is placed in a vacuum air quenching furnace for vacuum high-temperature solution treatment, and the heating tooling is made of austenitic stainless steel.

[0027] The beneficial effect of adopting the above further technical solution is: reducing the contact between stainless steel and iron during the processing and preparation process, and avoiding the increase of magnetism or magnetic conductivity of the silage machine feeding roller.

[0028] Furthermore, in step (2), the welded ground wire clamp is made of copper or copper alloy; and the weld surface is cleaned after welding.

[0029] The beneficial effects of adopting the above-mentioned further technical solution are: the welding ground wire clamp is made of copper or copper alloy, so that the current line is as short as possible and the current passes through the stainless steel as little as possible to improve the welding efficiency; after welding, the weld surface is cleaned, and the spatter, iron filings and oxide layer attached to the surface are cleaned with a wire brush or a grinder.

[0030] Furthermore, the method also includes the following steps: transporting and storing; using equipment made of wood, copper or stainless steel for transporting and storing.

[0031] The beneficial effect of adopting the above further technical solution is that since iron ions will inevitably be transferred when stainless steel comes into contact with iron, causing the stainless steel to be magnetic, during the process of incoming materials, bending, transportation, welding, storage, etc., wood, copper or stainless steel tooling is used for transportation to avoid contact with iron or minimize contact.

[0032] Another aspect of the present invention is to provide a silage machine feeding roller, which is prepared by the above preparation method.

[0033] Compared with the prior art, the present invention has the following technical effects:

[0034] By adopting the preparation method for eliminating the magnetism of a silage machine feed roller provided by the present invention, austenitic stainless steel whose internal structure does not contain ferrite and martensite is selected as the base material to prepare the silage machine feed roller, so that the magnetism of the feed roller is low; after welding, demagnetization treatment is performed through vacuum high-temperature solid solution treatment to further reduce the magnetism; through the combination of various steps, from controlling the generation of magnetism to demagnetizing magnetism, a silage machine feed roller that meets the requirements is obtained, ensuring that the metal detector can realize the metal detection function and can identify metals with different magnetic strengths. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Shows the location of the metal detector in the front lower roller weld of the silage machine feed roller;

[0036] Figure 2 A schematic diagram showing the route of the material passing through the front upper roller and the front lower roller (the arrows in the figure represent the material path).

[0037] Reference numerals:

[0038] 1. Front lower roller welding; 2. Metal detector; 3. Front upper roller welding. DETAILED DESCRIPTION

[0039] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may extend based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0040] Example

[0041] A preparation method for eliminating the magnetism of a silage machine feeding roller comprises the following steps:

[0042] (1) 316L stainless steel is used as the steel material to prepare the silage machine feed roller, and ER316 welding wire with chemical composition matching 316L stainless steel is selected for welding;

[0043] (2) During the welding process, a mixed gas with a ratio of 98% Ar + 2% CO2 was used as the welding atmosphere. 316L stainless steel was welded into the silage machine feed roller. The positioning fixtures, clamping mechanisms and other parts in contact with the steel used for welding were all made of 316L stainless steel. A copper ground wire clamp was used during welding. After welding, the weld surface was cleaned with a wire brush to clean the spatter, iron filings and oxide layer attached to the surface of the weld.

[0044] (3) The welded silage machine feed roller is subjected to vacuum high-temperature solution treatment. Specifically, the welded silage machine feed roller is placed in a heating fixture made of austenitic stainless steel, and then the heating fixture is placed in a vacuum gas quenching furnace for staged heating. The total heating and heat preservation time is 8.5 hours, including three heating stages, namely the first heating stage, the second heating stage and the third heating stage; wherein the first heating stage is heated from room temperature to 600°C, the heating temperature rise time is 2 hours, and the temperature rise time is 600°C. ℃ holding time is 1 hour; the second heating stage is heating from 600℃ to 800℃, the heating time is 1.5 hours, and the holding time at 800℃ is 1 hour; the third heating stage is heating from 800℃ to 1100℃, the heating time is 2 hours, and the holding time at 1100℃ is 1 hour; after the 1100℃ holding is completed, nitrogen is passed through the furnace for rapid cooling, and the cooling time is 90-120 minutes, until the temperature of the product drops below 100℃ before it is taken out of the furnace;

[0045] (4) The silage machine feed roller demagnetized by vacuum high-temperature solid solution treatment is subjected to pickling and passivation treatment. Specifically, a mixed pickling solution with a volume percentage of 80% H2O + 20% H2C2O4 (oxalic acid) is selected, and the silage machine feed roller is soaked for 3 hours, and the water temperature is maintained at 25°C; then the pickled and passivated silage machine feed roller is thoroughly rinsed with clean water and then completely dried.

[0046] (5) The obtained silage machine feed roller is placed in a wooden storage box for storage and subsequent transportation.

[0047] The metal detector is provided with different gears, and the larger the gear number, the stronger the sensitivity to metal. The silage machine feed roller welding loading vehicle prepared in the embodiment is tested and verified, and the test finds that the metal detectors in different gears can operate normally and can identify metals with different magnetic strengths. The silage machine feed roller welding prepared in the embodiment of the present invention meets the use requirements of the metal detector, and the metal detector can function normally when the silage machine is operating.

[0048] The magnetic properties of the silage machine feeding roller prepared by the preparation method for eliminating the magnetism of the silage machine feeding roller provided by the present invention can be reduced or even eliminated.

[0049] The present invention firstly selects raw materials with low magnetism to avoid strong magnetism of the equipment matrix after welding, then determines the welding auxiliary materials according to the selected materials, strictly controls the welding process, and demagnetizes the feeding roller after welding; the present invention solves the pain point problem of the metal detection technology of the silage machine feeding module by controlling the generation of magnetism to eliminate magnetism, can meet the requirements of normal operation of the metal detection system at different gears, and the metal detection system can identify metals with different magnetism. During the operation of the silage machine, it can avoid the hidden danger of foreign metals with different magnetism entering the fuselage to cause damage and destruction to the shredding module, avoids the labor, time and parts cost generated by subsequent maintenance, and fundamentally solves the quality problem of blade wear of the silage machine shredding module.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A preparation method for eliminating the magnetism of a silage machine feed roller, characterized in that: The following steps are involved: (1) Austenitic stainless steel is used to prepare the silage machine feed roller; (2) welding the base material with welding wire to form a silage machine feed roller; (3) vacuum high temperature solution treatment of the silage machine feed roller; (4) The silage machine feed roller is pickled and passivated.

2. The method for eliminating magnetism of a silage machine feed roller according to claim 1, characterized in that: The austenitic stainless steel is 316L stainless steel.

3. The method for eliminating magnetism of a silage machine feed roller according to claim 2, characterized in that: The welding wire is ER316.

4. The method for eliminating magnetism of a silage machine feed roller according to claim 1, characterized in that: In step (2), the welding atmosphere is a mixed gas consisting of 98% Ar and 2% CO2 by volume.

5. The method for eliminating magnetism of a silage machine feed roller according to claim 1, characterized in that: In step (3), the vacuum high temperature solution treatment includes a first heating stage, a second heating stage and a third heating stage; the first heating stage is from room temperature to 600°C, the second heating stage is 600-800°C, and the third heating stage is 800-1100°C.

6. The method for eliminating magnetism of a silage machine feed roller according to claim 5, characterized in that: The heating time of the first heating stage, the second heating stage and the third heating stage are all 1-2 hours, and the insulation time of the silage machine feeding roller at 600° C., 800° C. and 1100° C. are all 0.5-1 hour.

7. The method for eliminating magnetism of a silage machine feed roller according to claim 1, characterized in that: In step (4), the pickling and passivation treatment includes the following steps: soaking the silage machine feed roller in a mixed pickling solution for 2-4 hours, then rinsing the silage machine feed roller with clean water, and finally drying; the mixed pickling solution is a mixed solution of 80% H2O and 20% H2C2O4 by volume.

8. The method for eliminating magnetism of a silage machine feed roller according to claim 1, characterized in that: In step (2), the welding tooling and parts in contact with the substrate during welding are all made of austenitic stainless steel; in step (3), the silage machine feed roller is placed in a heating tooling, and then the heating tooling is placed in a vacuum air quenching furnace for vacuum high-temperature solution treatment, and the heating tooling is made of austenitic stainless steel.

9. The method for eliminating magnetism of a silage machine feed roller according to any one of claims 1 to 8, characterized in that: The following steps are also included: Transfer and storage: Use equipment made of wood, copper or stainless steel for transfer and storage.

10. A silage machine feeding roller, characterized in that: The method is prepared according to any one of claims 1 to 9.

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