Performance improving device for hydraulic tensioning system of vertical roller mill

Abstract

The utility model relates to the technical field of vertical roller mills, in particular to a vertical roller mill hydraulic tensioning system performance improving device which comprises an oil tank, a high-pressure pump, a three-position four-way reversing valve, an electromagnetic ball valve, a hydraulic control one-way valve, a first tensioning pipeline, a second tensioning pipeline, a first oil pipe, a second oil pipe, a third oil pipe, a fourth oil pipe, a fifth oil pipe, an adjusting structure and a tensioning hydraulic cylinder. The first oil pipe is connected with the oil tank and the first tensioning pipeline, a first high-pressure ball valve and a second high-pressure ball valve are arranged on the first oil pipe, the first oil pipe is communicated with a first outlet of the three-position four-way reversing valve through a sixth oil pipe, and the second high-pressure ball valve is arranged on the portion, between the sixth oil pipe and the oil tank, of the first oil pipe. An inlet of the hydraulic control one-way valve is communicated with the sixth oil pipe through a seventh oil pipe, and the second oil pipe is communicated with the oil tank and the output end of the electromagnetic ball valve. According to the roller lifting device, the roller lifting time when a roller lifting command is executed can be shortened, abnormal vibration caused by too long roller lifting time is prevented, and damage to equipment caused by frequent vibration stop of the mill is also avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of vertical roller mills, in particular to a performance improvement device for a hydraulic tensioning system of a vertical roller mill. Background Art

[0002] The working principle of a vertical roller mill is as follows: a high-voltage motor drives a reducer, which rotates the millstone. The material to be ground is fed from a feeding device through a chute into the center of the rotating millstone. The centrifugal force of the rotation moves the material toward the periphery of the millstone and into the grinding track. Four grinding rollers apply pressure to the material through a hydraulic tensioning device, crushing it through compression, grinding, and shearing. Hot air drawn from the kiln exhaust is rapidly and evenly ejected upward through air rings on both sides of the millstone. The ground material is lifted by the rapid airflow from the air rings, and coarse material is blown back to the millstone for re-grinding. Fine material is carried by the hot air into a separator for separation. Qualified fine powder exits the mill with the airflow and is collected by the dust collector as the finished product. Unqualified coarse powder falls back to the millstone under the action of the separator blades and is re-ground with the newly fed material. This cycle completes the entire grinding process. The grinding roller pressure device pressurizes the grinding roller to grind the material through the tensioning hydraulic cylinder. There are four groups of tensioning hydraulic cylinders with a working pressure of 6.2 to 7.5 MPa. The built-in accumulator is pre-charged with nitrogen pressure to buffer and stabilize the tensioning device. The nitrogen pressure is adjusted to 60% + 10% of the grinding roller tensioning pressure. Among them, the device that provides kinetic energy for the grinding roller tensioning hydraulic cylinder is the hydraulic station and control system.

[0003] Under normal operating conditions, the oil in the oil tank enters the rod chamber of the hydraulic cylinder and returns to the rodless chamber. However, in the actual oil circuit, the return oil hole of the valve block in the return oil circuit is small, resulting in the hydraulic station replenishing oil and pressurizing the rodless chamber when the roller mill executes the roller lifting command, but the rod chamber of the hydraulic cylinder cannot quickly discharge the oil back to the oil tank, resulting in slow unloading of the oil pressure in the rod chamber, causing the roller mill to lift the roller for a long time. After testing, the roller lifting time is about 8 minutes under the operating state. The roller lifting speed is too slow, which will cause abnormal vibration of the roller mill. Frequent vibration stops will also cause great damage to the equipment. In view of this, the above hydraulic system is improved accordingly. Utility Model Content

[0004] The purpose of this utility model is to address the above-mentioned deficiencies and provide a performance improvement device for the hydraulic tensioning system of a vertical roller mill, which can shorten the roller lifting time when executing the roller lifting command, prevent abnormal vibration caused by too long roller lifting time, and avoid damage to the equipment caused by frequent vibration and shutdown of the mill.

[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A device for improving the performance of a hydraulic tensioning system of a vertical roller mill, comprising an oil tank, a high-pressure pump, a three-position four-way directional control valve, an electromagnetic ball valve, a pilot-operated check valve, a tensioning pipeline 1, a tensioning pipeline 2, an oil pipe 1, an oil pipe 2, an oil pipe 3, an oil pipe 4, an oil pipe 5 and an adjusting structure. Four tensioning hydraulic cylinders are connected in series on the tensioning pipeline 1 and the tensioning pipeline 2. The rod chamber of the tensioning hydraulic cylinder is communicated with the tensioning pipeline 1, and the rodless chamber of the tensioning hydraulic cylinder is communicated with the tensioning pipeline 2. The oil pipe 1 connects the oil tank and the tensioning pipeline 1. A high-pressure ball valve 1 and a high-pressure ball valve 2 are arranged on the oil pipe 1. The oil pipe 1 is communicated with the outlet 1 of the three-position four-way directional control valve through an oil pipe 6. The high-pressure ball valve 2 is arranged on the oil pipe 1 between the oil pipe 6 and the oil tank. The inlet of the pilot-operated check valve is communicated with the oil pipe 6 through an oil pipe 7. The oil pipe 2 connects the oil tank and the output end of the electromagnetic ball valve. The input end of the electromagnetic ball valve is communicated with the oil pipe 6 through an oil pipe 8. The outlet of the pilot-operated check valve is communicated with the oil pipe 2 through an oil pipe 9. The oil pipe 3 connects the tensioning pipeline 2 and the oil tank. The oil pipe 4 is communicated with the inlet 1 of the three-position four-way directional control valve. The high-pressure pump is arranged on the oil pipe 4. The oil pipe 5 connects the tensioning pipeline 2 and the oil tank. The tensioning pipeline 2 is communicated with the inlet 2 of the three-position four-way directional control valve through an oil pipe 10. The outlet 2 of the three-position four-way directional control valve is communicated with the oil pipe 5 through an oil pipe 11. The adjusting structure is used to adjust the hydraulic pressure in the tensioning pipeline 1 and the tensioning pipeline 2.

[0007] Further, the adjusting structure comprises a shuttle valve and an adjusting directional control valve. The inlet 1 of the shuttle valve is communicated with the tensioning pipeline 2 through an adjusting pipe 1. The inlet 2 of the shuttle valve is communicated with the oil pipe 1 between the high-pressure ball valve 1 and the high-pressure ball valve 2 through an adjusting pipe 2. The outlet of the shuttle valve is communicated with the inlet of the adjusting directional control valve through an adjusting pipe 3. The outlet of the adjusting directional control valve is communicated with the oil pipe 2 through an adjusting pipe 4.

[0008] Further, a filter is arranged on the oil pipe 4, and the filter is arranged between the high-pressure pump and the three-position four-way directional control valve.

[0009] Further, a check valve is arranged on the oil pipe 6, and the check valve is arranged between the three-position four-way directional control valve and the oil pipe 8.

[0010] Further, a pressure relief pipe is connected between the oil pipe 4 and the oil pipe 5, and a pressure relief valve is arranged on the pressure relief pipe.

[0011] The beneficial effects of the utility model are:

[0012] 1. During normal operation, high-pressure ball valve II is closed and high-pressure ball valve I is open. The hydraulic oil in the fuel tank passes through oil pipe IV, high-pressure pump, inlet I of the three-position four-way directional control valve, the three-position four-way directional control valve, outlet I of the three-position four-way directional control valve, oil pipe VI, oil pipe I, and tensioning pipe I to enter the rod chamber of the tensioning hydraulic cylinder, and returns to the fuel tank through the rodless chamber of the tensioning hydraulic cylinder, tensioning pipe II, and oil pipe III. At the same time, it returns to the fuel tank through tensioning pipe II, oil pipe X, inlet II of the three-position four-way directional control valve, outlet II of the three-position four-way directional control valve, oil pipe XI, and oil pipe V.

[0013] 2. When the hydraulic pressure of the high-pressure pump is too high, the hydraulic oil in the fuel tank passes through oil pipe IV, high-pressure pump, inlet I of the three-position four-way directional control valve, the three-position four-way directional control valve, outlet I of the three-position four-way directional control valve, oil pipe VI, and oil pipe VIII to enter the electromagnetic ball valve. After relieving pressure through the electromagnetic ball valve, it returns to the fuel tank through oil pipe II.

[0014] 3. When the hydraulic pressure of the high-pressure pump is too low, the hydraulic oil in the fuel tank passes through oil pipe IV, high-pressure pump, inlet I of the three-position four-way directional control valve, the three-position four-way directional control valve, outlet II of the three-position four-way directional control valve, oil pipe XI, and oil pipe V to return to the fuel tank.

[0015] 4. When lifting the roller, the hydraulic oil in the fuel tank passes through oil pipe III and tensioning pipe II to enter the rodless chamber of the tensioning hydraulic cylinder. At the same time, the hydraulic oil in the fuel tank passes through oil pipe V, oil pipe XI, outlet II of the three-position four-way directional control valve, inlet II of the three-position four-way directional control valve, oil pipe X, and tensioning pipe II to enter the rodless chamber of the tensioning hydraulic cylinder. The hydraulic oil in the rod chamber of the tensioning hydraulic cylinder returns to the fuel tank through tensioning pipe I, oil pipe I, oil pipe VI, oil pipe VII, pilot-operated check valve, oil pipe IX, and oil pipe II. By adjusting the structure to adjust the hydraulic pressure in tensioning pipe I and tensioning pipe II, the roller lifting time during the running state is shortened.

[0016] The utility model can shorten the roller lifting time when executing the roller lifting command, prevent abnormal vibration caused by too long roller lifting time, and also avoid damage to the equipment caused by frequent vibration stoppage of the mill. Brief Description of the Drawings

[0017] Figure 1 is a schematic diagram of the hydraulic principle of the utility model;

[0018] Reference numerals: fuel tank 1; high-pressure pump 2; three-position four-way directional control valve 3; electromagnetic ball valve 4; pilot-operated check valve 5; tensioning pipeline 1 6; tensioning pipeline 2 7; oil pipe 1 8; high-pressure ball valve 1 801; high-pressure ball valve 2 802; oil pipe 2 9; oil pipe 3 10; oil pipe 4 11; oil pipe 5 12; tensioning hydraulic cylinder 13; oil pipe 6 14; oil pipe 7 15; oil pipe 8 16; oil pipe 9 17; oil pipe 10 18; oil pipe 11 19; shuttle valve 201; regulating directional control valve 202; regulating pipe 1 203; regulating pipe 2 204; regulating pipe 3 205; regulating pipe 4 206; filter 21; check valve 22; pressure relief pipe 23; pressure relief valve 24. Detailed implementation manner

[0019] As Figure 1 shown, a device for improving the performance of a hydraulic tensioning system of a vertical roller mill includes a fuel tank 1, a high-pressure pump 2, a three-position four-way directional control valve 3, an electromagnetic ball valve 4, a pilot-operated check valve 5, a tensioning pipeline 1 6, a tensioning pipeline 2 7, an oil pipe 1 8, an oil pipe 2 9, an oil pipe 3 10, an oil pipe 4 11, an oil pipe 5 12 and an adjusting structure. Four tensioning hydraulic cylinders 13 are connected in series on the tensioning pipeline 1 6 and the tensioning pipeline 2 7. The rod chamber of the tensioning hydraulic cylinder 13 is communicated with the tensioning pipeline 1 6, and the rodless chamber of the tensioning hydraulic cylinder 13 is communicated with the tensioning pipeline 2 7. The oil pipe 1 8 connects the fuel tank 1 and the tensioning pipeline 1 6. A high-pressure ball valve 1 801 and a high-pressure ball valve 2 802 are arranged on the oil pipe 1 8. The oil pipe 1 8 is communicated with the first outlet of the three-position four-way directional control valve 3 through an oil pipe 6 14. The high-pressure ball valve 2 802 is arranged on the oil pipe 1 8 between the oil pipe 6 14 and the fuel tank 1. The inlet of the pilot-operated check valve 5 is communicated with the oil pipe 6 14 through an oil pipe 7 15. The oil pipe 2 9 connects the fuel tank 1 and the output end of the electromagnetic ball valve 4. The input end of the electromagnetic ball valve 4 is communicated with the oil pipe 6 14 through an oil pipe 8 16. The outlet of the pilot-operated check valve 5 is communicated with the oil pipe 2 9 through an oil pipe 9 17. The oil pipe 3 10 connects the tensioning pipeline 2 7 and the fuel tank 1. The oil pipe 4 11 is communicated with the first inlet of the three-position four-way directional control valve 3. The high-pressure pump 2 is arranged on the oil pipe 4 11. The oil pipe 5 12 connects the tensioning pipeline 2 7 and the fuel tank 1. The tensioning pipeline 2 7 is communicated with the second inlet of the three-position four-way directional control valve 3 through an oil pipe 10 18. The second outlet of the three-position four-way directional control valve 3 is communicated with the oil pipe 5 12 through an oil pipe 11 19. The adjusting structure is used to adjust the hydraulic pressure in the tensioning pipeline 1 6 and the tensioning pipeline 2 7.

[0020] During normal use, the high-pressure ball valve II 802 is closed and the high-pressure ball valve I 801 is open. The hydraulic oil in the oil tank 1 passes through the oil pipe IV 11, high-pressure pump 2, inlet I of the three-position four-way directional control valve 3, three-position four-way directional control valve 3, outlet I of the three-position four-way directional control valve 3, oil pipe VI 14, oil pipe I 8, and tensioning pipe I 6 to enter the rod chamber of the tensioning hydraulic cylinder 13, and returns to the oil tank 1 through the rodless chamber of the tensioning hydraulic cylinder 13, tensioning pipe II 7, and oil pipe III 10. At the same time, it returns to the oil tank 1 through the tensioning pipe II 7, oil pipe X 18, inlet II of the three-position four-way directional control valve 3, outlet II of the three-position four-way directional control valve 3, oil pipe XI 19, and oil pipe V 12.

[0021] When the hydraulic pressure of the high-pressure pump 2 is too high, the hydraulic oil in the oil tank 1 passes through the oil pipe IV 11, high-pressure pump 2, inlet I of the three-position four-way directional control valve 3, three-position four-way directional control valve 3, outlet I of the three-position four-way directional control valve 3, oil pipe VI 14, and oil pipe VIII 16 to enter the electromagnetic ball valve 4. After pressure relief through the electromagnetic ball valve 4, it returns to the oil tank 1 through the oil pipe II 9.

[0022] When the hydraulic pressure of the high-pressure pump 2 is too low, the hydraulic oil in the oil tank 1 passes through the oil pipe IV 11, high-pressure pump 2, inlet I of the three-position four-way directional control valve 3, three-position four-way directional control valve 3, outlet II of the three-position four-way directional control valve 3, oil pipe XI 19, and oil pipe V 12 to return to the oil tank 1.

[0023] When lifting the roller, the hydraulic oil in the oil tank 1 passes through the oil pipe III 10 and tensioning pipe II 7 to enter the rodless chamber of the tensioning hydraulic cylinder 13. At the same time, the hydraulic oil in the oil tank 1 passes through the oil pipe V 12, oil pipe XI 19, outlet II of the three-position four-way directional control valve 3, inlet II of the three-position four-way directional control valve 3, oil pipe X 18, and tensioning pipe II 7 to enter the rodless chamber of the tensioning hydraulic cylinder 13. The hydraulic oil in the rod chamber of the tensioning hydraulic cylinder 13 returns to the oil tank 1 through the tensioning pipe I 6, oil pipe I 8, oil pipe VI 14, oil pipe VII 15, pilot-operated check valve 5, oil pipe IX 17, and oil pipe II 9. By adjusting the structure to adjust the hydraulic pressure in the tensioning pipe I 6 and tensioning pipe II 7, the roller lifting time in the running state is shortened. The utility model can shorten the roller lifting time when the roller lifting command is executed, prevent abnormal vibration caused by too long roller lifting time, and also avoid damage to the equipment caused by frequent vibration stops of the mill.

[0024] As Figure 1As shown in the figure, the adjustment structure includes a shuttle valve 201 and an adjustment directional control valve 202. One inlet of the shuttle valve 201 is connected to the tensioning pipeline two 7 through an adjustment pipe one 203. The second inlet of the shuttle valve 201 is connected to an oil pipe one 8 between a high-pressure ball valve one 801 and a high-pressure ball valve two 802 through an adjustment pipe two 204. The outlet of the shuttle valve 201 is connected to the inlet of the adjustment directional control valve 202 through an adjustment pipe three 205. The outlet of the adjustment directional control valve 202 is connected to an oil pipe two 9 through an adjustment pipe four 206. In this embodiment, when the hydraulic pressure in the tensioning pipeline one 6 is too high, the hydraulic oil in the tensioning pipeline one 6 enters the shuttle valve 201 through the oil pipe one 8 and the adjustment pipe two 204, and returns to the oil tank 1 through the adjustment pipe three 205, the adjustment directional control valve 202, the adjustment pipe four 206 and the oil pipe two 9. At the same time, the high-pressure ball valve two 802 is gradually pushed open by the high pressure, and the oil in the tensioning pipeline one 6 can also directly return to the oil tank through the high-pressure ball valve two 802, so that the oil pressure in the rod chamber and the oil pressure in the non-rod chamber are quickly balanced. When the hydraulic pressure in the tensioning pipeline two 7 is too high, the hydraulic oil in the tensioning pipeline two 7 enters the shuttle valve 201 through the adjustment pipe one 203, and returns to the oil tank 1 through the adjustment pipe three 205, the adjustment directional control valve 202, the adjustment pipe four 206 and the oil pipe two 9, so that the oil pressure in the rod chamber and the oil pressure in the non-rod chamber are quickly balanced, preventing abnormal vibration caused by too long roll-lifting time, and also avoiding damage to the equipment caused by frequent vibration and shutdown of the mill.

[0025] As Figure 1 shown, a filter 21 is provided on the oil pipe four 11, and the filter 21 is arranged between the high-pressure pump 2 and the three-position four-way directional control valve 3. In this embodiment, the filter 21 can filter the oil.

[0026] As Figure 1 shown, a check valve 22 is provided on the oil pipe six 14, and the check valve 22 is arranged between the three-position four-way directional control valve 3 and the oil pipe eight 16. In this embodiment, the check valve 22 can prevent the oil from flowing back into the three-position four-way directional control valve 3 when the roll-lifting command is executed.

[0027] As Figure 1 shown, a pressure relief pipe 23 is connected between the oil pipe four 11 and the oil pipe five 12, and a pressure relief valve 24 is provided on the pressure relief pipe 23. In this embodiment, the pressure relief pipe 23 and the pressure relief valve 24 can relieve the pressure of the pipeline.

[0028] The specific embodiments described herein are merely illustrative of the present invention. Those skilled in the technical field to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, but will not deviate from the scope defined by the present invention.

Claims

1. A device for improving the performance of a hydraulic tensioning system of a vertical roller mill, characterized in that: It includes a fuel tank (1), a high-pressure pump (2), a three-position four-way directional control valve (3), an electromagnetic ball valve (4), a pilot-operated check valve (5), a tensioning pipeline one (6), a tensioning pipeline two (7), an oil pipe one (8), an oil pipe two (9), an oil pipe three (10), an oil pipe four (11), an oil pipe five (12) and an adjusting structure. Four tensioning hydraulic cylinders (13) are connected in series on the tensioning pipeline one (6) and the tensioning pipeline two (7). The rod chamber of the tensioning hydraulic cylinder (13) communicates with the tensioning pipeline one (6), and the rodless chamber of the tensioning hydraulic cylinder (13) communicates with the tensioning pipeline two (7). The oil pipe one (8) connects the fuel tank (1) and the tensioning pipeline one (6). A high-pressure ball valve one (801) and a high-pressure ball valve two (802) are arranged on the oil pipe one (8). The oil pipe one (8) communicates with the outlet one of the three-position four-way directional control valve (3) through an oil pipe six (14). The high-pressure ball valve two (802) is arranged on the oil pipe one (8) between the oil pipe six (14) and the fuel tank (1). The inlet of the pilot-operated check valve (5) communicates with the oil pipe six (14) through an oil pipe seven (15). The oil pipe two (9) connects the fuel tank (1) and the output end of the electromagnetic ball valve (4). The input end of the electromagnetic ball valve (4) communicates with the oil pipe six (14) through an oil pipe eight (16). The outlet of the pilot-operated check valve (5) communicates with the oil pipe two (9) through an oil pipe nine (17). The oil pipe three (10) connects the tensioning pipeline two (7) and the fuel tank (1). The oil pipe four (11) communicates with the inlet one of the three-position four-way directional control valve (3). The high-pressure pump (2) is arranged on the oil pipe four (11). The oil pipe five (12) connects the tensioning pipeline two (7) and the fuel tank (1). The tensioning pipeline two (7) communicates with the inlet two of the three-position four-way directional control valve (3) through an oil pipe ten (18). The outlet two of the three-position four-way directional control valve (3) communicates with the oil pipe five (12) through an oil pipe eleven (19). The adjusting structure is used to adjust the hydraulic pressure in the tensioning pipeline one (6) and the tensioning pipeline two (7).

2. The performance improvement device of a vertical roller mill hydraulic tensioning system according to claim 1, characterized in that, The adjusting structure includes a shuttle valve (201) and an adjusting directional control valve (202). The inlet one of the shuttle valve (201) communicates with the tensioning pipeline two (7) through an adjusting pipe one (203). The inlet two of the shuttle valve (201) communicates with the oil pipe one (8) between the high-pressure ball valve one (801) and the high-pressure ball valve two (802) through an adjusting pipe two (204). The outlet of the shuttle valve (201) communicates with the inlet of the adjusting directional control valve (202) through an adjusting pipe three (205). The outlet of the adjusting directional control valve (202) communicates with the oil pipe two (9) through an adjusting pipe four (206).

3. The performance improvement device for the hydraulic tensioning system of a vertical roller mill according to claim 1, characterized in that, A filter (21) is arranged on the oil pipe four (11). The filter (21) is arranged between the high-pressure pump (2) and the three-position four-way directional control valve (3).

4. An apparatus for improving the performance of a hydraulic tensioning system of a vertical roller mill according to claim 1, characterized in that, A check valve (22) is arranged on the oil pipe six (14). The check valve (22) is arranged between the three-position four-way directional control valve (3) and the oil pipe eight (16).

5. The performance improvement device for the hydraulic tensioning system of a vertical roller mill according to claim 1, characterized in that, A pressure relief pipe (23) is connected between the fourth oil pipe (11) and the fifth oil pipe (12), and a pressure relief valve (24) is provided on the pressure relief pipe (23).

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