Mining bimetallic chain wheel and manufacturing method

Abstract

The invention discloses a mining bimetallic chain wheel and a manufacturing method thereof, and the manufacturing method comprises the following steps: carrying out forging treatment on a bimetallic profile blank by adopting a three-fire forging forming mode; normalizing the chain wheel formed by forging; carrying out rough machining on a tooth groove, an inner hole, an outer circle and an end face on the normalized chain wheel blank; quenching and tempering heat treatment is conducted on the chain wheel base body; semi-finish machining is conducted on the outer circle and the tooth form of the chain wheel base body; and finish machining of the teeth. The chain wheel sheet material can meet the requirements that a chain wheel is low in appearance hardness, high in abrasion resistance and not prone to abrasion in the using process. The material of the connecting sleeve can meet the requirements of low appearance hardness and soft inner hole hardness of the chain wheel, and teeth are easy to manufacture. And the blank three-fire forging process is adopted, so that grains in the blank can be refined.

Description

Technical Field

[0001] The invention relates to the technical field of mining scraper conveyors, and in particular to a mining bimetallic sprocket and a manufacturing method thereof. Background Art

[0002] In the three-machine-one-frame mining equipment, the scraper conveyor and the transfer machine use the motor to drive the sprocket shaft group to transmit power and transport. The sprocket shaft group meshes with the mining chain to make the whole machine run and transmit coal. The sprocket is the core part for transmitting power in the scraper conveyor. During the use of the equipment, the sprocket chain nest is subjected to huge alternating loads and additional impact loads during the meshing process with the round chain, resulting in serious wear of the sprocket chain nest. The sprocket frequently fails due to wear during use, resulting in the sprocket being not wear-resistant and having a short service life. The mining sprocket is a consumable part with a lifespan of only 3-5 months. In order to ensure the safe and stable operation of the sprocket shaft group, it is necessary to replace the damaged sprocket frequently. Summary of the invention

[0003] In order to solve the technical problems existing in the above-mentioned technology, it is necessary to provide a method for manufacturing a bimetallic sprocket for mining.

[0004] A method for manufacturing a bimetallic sprocket for mining comprises the following steps: Step S1: forging the bimetal profile blank by three-fire forging; Step S2: normalizing the forged sprocket; Step S3: rough machining the tooth groove, inner hole, outer circle and end face of the sprocket blank after normalizing; Step S4: performing a quenching and tempering heat treatment on the sprocket substrate; Step S5: semi-finishing the outer circle and tooth profile of the sprocket base; Step S6: finishing the gears.

[0005] Preferably, in step S1, the bimetallic profile blank is forged in the following manner: The bimetallic profile blank is heated to the initial forging temperature of 1250±10°C, and then the bimetallic profile blank is forged after being kept heated for 3 hours; When the forging reaches the final forging temperature below 850℃, it is cooled naturally to above 100℃, the burrs on the dividing line are manually polished, and the billet is returned to the furnace and heated to the initial forging temperature. After heat preservation and heating for 3 hours, the forging is continued; According to the above steps, the bimetal profile blank is forged three times continuously.

[0006] Preferably, in step S2, the normalizing temperature is 860°C-890°C, and the temperature is kept for 3.5 hours.

[0007] Preferably, in step S4, the sprocket matrix is ​​subjected to tempering heat treatment by overall quenching + overall low-temperature tempering + high-temperature tempering of the inner hole.

[0008] Preferably, the overall quenching temperature is 880°C-920°C, the insulation time is 3.5 hours, and the quenching medium is oil.

[0009] Preferably, the overall tempering temperature is 200±10°C, the heat preservation time is 3.5h, and the outer circle hardness is HRC58-62.

[0010] Preferably, the inner hole of the sprocket is subjected to medium frequency tempering, the tempering temperature is 650±10°C, the holding time is 2h, and the inner hole hardness is HB280-320.

[0011] There is also a need to provide a bimetallic sprocket for mining.

[0012] A bimetallic sprocket for mining is manufactured by adopting the above-mentioned bimetallic sprocket manufacturing method for mining.

[0013] Preferably, the mining bimetallic sprocket comprises a connecting sleeve and sprocket plates arranged at both ends of the connecting sleeve.

[0014] Preferably, the sprocket is made according to the following metal element composition: C: 0.35-0.45%, Mn: 0.5-0.85%, Si: 0.2-0.37%, S: ≤0.005%, P: ≤0.015%, Cr: 2.0-2.6%, Ni: 1.5-2.0%, Mo: 0.25-0.6%, V: 0.15-0.35%, the rest is Fe and unavoidable impurities; The connecting sleeve is made according to the following metal element composition: C: 0.35-0.42%, Mn: 0.3-0.6%, Si: 0.2-0.45%, S: ≤0.015%, P: ≤0.015%, Cr: 1.35-1.65%, Ni: ≤0.3%, Al: 0.7-1.1%, Mo: 0.15-0.25%, Cu: ≤0.3%, and the rest are Fe and unavoidable impurities.

[0015] Compared with the prior art, the bimetallic sprocket for mining and the manufacturing method provided by the present invention strengthen the solid solution, purify the grain boundaries and refine the grains by adding appropriate amounts of alloy elements and microalloying design, thereby improving hardenability and dispersing and precipitating impurities. Under medium and low impact loads, the surface hardness of the sprocket nest is further improved after the chain is engaged through strain-induced phase transformation self-strengthening, effectively reducing the wear and failure of the nest. The sprocket sheet material can meet the requirements of low sprocket appearance hardness and high wear resistance, and is not easy to wear during use. The connecting sleeve material can meet the requirements of low sprocket appearance hardness and soft inner hole hardness, which is easy to make teeth. The blank 3-fire forging process is adopted to refine the grains inside the blank. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the product structure of the bimetallic sprocket of the present invention.

[0018] Figure 2 Schematic diagram of the bimetallic profile blank of the present invention.

[0019] Figure 3 It is a schematic diagram of the bimetallic profile blank after forging of the present invention.

[0020] In the figure: DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the description of the present invention, it should be understood that the terms "upper", "middle", "outer", "inner", "lower" and the like indicating directions or positional relationships are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0023] In one embodiment, the present invention provides a method for manufacturing a bimetallic sprocket for mining, comprising the following steps: Step S1: forging the bimetal profile blank by three-fire forging; Step S2: normalizing the forged sprocket; Step S3: rough machining the tooth groove, inner hole, outer circle and end face of the sprocket blank after normalizing; Step S4: performing a quenching and tempering heat treatment on the sprocket substrate; Step S5: semi-finishing the outer circle and tooth profile of the sprocket base; at this time, a 20mm machining allowance should be reserved at the junction of the sprocket base and the connecting sleeve. Step S6: finishing the gears.

[0024] Among them, the following methods are used when forging the bimetallic profile blank: The bimetallic profile blank is heated to the initial forging temperature of 1250±10°C, and then the bimetallic profile blank is forged after being kept heated for 3 hours; When the forging reaches the final forging temperature below 850℃, it is cooled naturally to above 100℃, the burrs on the dividing line are manually polished, and the billet is returned to the furnace and heated to the initial forging temperature. After heat preservation and heating for 3 hours, the forging is continued; According to the above steps, the bimetal profile blank is forged three times continuously, so that the grain inside the blank can be refined.

[0025] Among them, when the forged sprocket is normalized, the normalizing temperature is 860℃-890℃, and the temperature is kept for 3.5 hours.

[0026] Among them, when the sprocket matrix is ​​subjected to tempering heat treatment, the method of overall quenching + overall low-temperature tempering + high-temperature tempering of the inner hole is adopted.

[0027] During overall quenching, the overall quenching temperature is 880℃-920℃, the insulation time is 3.5h, and the quenching medium is oil.

[0028] During the overall low-temperature tempering, the overall tempering temperature is 200±10℃, the temperature is kept for 3.5h, and the medium is air, room temperature, and the outer circle hardness of the quenching and tempering heat treatment is HRC58~62.

[0029] When tempering the inner hole at high temperature, the inner hole of the sprocket adopts medium frequency tempering, the tempering temperature is 650±10℃, the holding time is 2h, and the inner hole hardness is HB280-320.

[0030] In one embodiment, the present invention provides a bimetallic sprocket for mining, which is manufactured using a bimetallic sprocket manufacturing method for mining.

[0031] Specifically, the mining bimetallic sprocket comprises a connecting sleeve and sprocket plates arranged at both ends of the connecting sleeve.

[0032] Specifically, the sprocket is manufactured according to the following metal element composition: C: 0.35-0.45%, Mn: 0.5-0.85%, Si: 0.2-0.37%, S: ≤0.005%, P: ≤0.015%, Cr: 2.0-2.6%, Ni: 1.5-2.0%, Mo: 0.25-0.6%, V: 0.15-0.35%, and the rest are Fe and unavoidable impurities; the formed sprocket has a tensile strength σb ≥ 1350MPa and a yield strength σs ≥ 1000MPa.

[0033] The connecting sleeve is made of the following metal elements: C: 0.35-0.42%, Mn: 0.3-0.6%, Si: 0.2-0.45%, S: ≤0.015%, P: ≤0.015%, Cr: 1.35-1.65%, Ni: ≤0.3%, AL: 0.7-1.1%, Mo: 0.15-0.25%, Cu: ≤0.3%, the rest is Fe and unavoidable impurities. After heat treatment, the nitrided parts with precise dimensions have mechanical properties σb ≥ 1000MPa and yield strength σs ≥ 850MPa. It has good processing performance in mechanical processing and is easy to make gears.

[0034] The metal elements of the sprocket and the connecting sleeve are made into blanks by electric furnace smelting process according to corresponding proportions, the sprocket blanks and the connecting sleeve blanks are formed by bimetallic forging, the forging loss and the blank weight of the connecting sleeve are accurately calculated, and the sprocket and the connecting sleeve blanks are rolled into bimetallic profile blanks, such as Figure 2 shown.

[0035] What is disclosed above is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for manufacturing a bimetallic sprocket for mining, characterized in that: The following steps are included: Step S1: forging the bimetal profile blank by three-fire forging; Step S2: normalizing the forged sprocket; Step S3: rough machining the tooth groove, inner hole, outer circle and end face of the sprocket blank after normalizing; Step S4: performing a quenching and tempering heat treatment on the sprocket substrate; Step S5: semi-finishing the outer circle and tooth profile of the sprocket base; Step S6: finishing the gears.

2. The method for manufacturing a bimetallic sprocket for mining according to claim 1, characterized in that: In step S1, the bimetallic sprocket blank is forged in the following manner: The bimetallic profile blank is heated to the initial forging temperature of 1250±10°C, and then the bimetallic profile blank is forged after being kept heated for 3 hours; When the forging reaches the final forging temperature below 850℃, it is cooled naturally to above 100℃, the burrs on the dividing line are manually polished, and the billet is returned to the furnace and heated to the initial forging temperature. After heat preservation and heating for 3 hours, the forging is continued; According to the above steps, the bimetal profile blank is forged three times continuously.

3. The method for manufacturing a bimetallic sprocket for mining according to claim 1, characterized in that: In step S2, the normalizing temperature is 860°C-890°C, and the temperature is kept for 3.5 hours.

4. The method for manufacturing a bimetallic sprocket for mining according to claim 1, characterized in that: In step S4, the sprocket base body is subjected to tempering heat treatment by overall quenching + overall low-temperature tempering + high-temperature tempering of the inner hole.

5. The method for manufacturing a bimetallic sprocket for mining according to claim 4, characterized in that: The overall quenching temperature is 880℃-920℃, the insulation time is 3.5h, and the quenching medium is oil.

6. The method for manufacturing a bimetallic sprocket for mining according to claim 4 or 5, characterized in that: The overall tempering temperature is 200±10℃, the insulation time is 3.5h, and the outer circle hardness is HRC58~62.

7. The method for manufacturing a bimetallic sprocket for mining according to claim 6, characterized in that: The inner hole of the sprocket is tempered by medium frequency, the tempering temperature is 650±10℃, the holding time is 2h, and the inner hole hardness is HB280-320.

8. A bimetallic sprocket for mining, characterized in that: The mining bimetallic sprocket is manufactured by the manufacturing method of any one of claims 1 to 7.

9. The bimetallic sprocket for mining according to claim 8, characterized in that: The mining bimetal sprocket comprises a connecting sleeve and sprocket plates arranged at two ends of the connecting sleeve.

10. The bimetallic sprocket for mining according to claim 9, characterized in that: The sprocket is manufactured according to the following metal element composition: C: 0.35-0.45%, Mn: 0.5-0.85%, Si: 0.2-0.37%, S: ≤0.005%, P: ≤0.015%, Cr: 2.0-2.6%, Ni: 1.5-2.0%, Mo: 0.25-0.6%, V: 0.15-0.35%, the rest is Fe and unavoidable impurities; The connecting sleeve is made according to the following metal element composition: C: 0.35-0.42%, Mn: 0.3-0.6%, Si: 0.2-0.45%, S: ≤0.015%, P: ≤0.015%, Cr: 1.35-1.65%, Ni: ≤0.3%, Al: 0.7-1.1%, Mo: 0.15-0.25%, Cu: ≤0.3%, and the rest are Fe and unavoidable impurities.

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