A roller mill with hydraulic loading and adjustment system

Abstract

One aspect of the present invention proposes a hydraulic loading and adjustment system, which includes at least one hydraulic loading and adjustment unit and a hydraulic control system, each of the at least one hydraulic loading and adjustment unit includes: a hydraulic cylinder; a hydraulic pump station, the hydraulic pump station is respectively connected to the rod chamber and the rodless chamber of the hydraulic cylinder; a first accumulator, the first accumulator is connected to the rod chamber of the hydraulic cylinder through a high-pressure hose; and a second accumulator, the second accumulator is connected to the rodless chamber of the hydraulic cylinder through a high-pressure hose, wherein the hydraulic control system is connected to the hydraulic pump station to control the amount of hydraulic oil provided to the hydraulic cylinder. The roller mill with a hydraulic loading and adjustment system provided by the present invention can dynamically adjust the loading force according to the material characteristics, so as to quickly respond to the change of the thickness of the material bed in the roller mill during the grinding process of the material, absorb the impact vibration of the material bed when the mill is working, and improve the running stability of the mill.

Description

Technical Field

[0001] The invention relates to the field of hydraulic loading and adjustment, and more particularly to a roller mill with a hydraulic loading and adjustment system. Background Art

[0002] During the operation of the roller mill, the piston rod of the hydraulic cylinder applies pressure to the roller of the mill to grind and crush the material. The rodless chamber of the hydraulic cylinder is directly connected to the oil tank of the hydraulic pump station and has no working pressure. During the feeding process of the mill, the feeding amount changes and the material particle size is often uneven. The feeding amount changes will cause the thickness of the material bed to change, and the material particle size changes will also cause the thickness of the local material bed to suddenly increase or decrease. These conditions will cause the roller to frequently rise and fall on the material bed and cause vibration.

[0003] In the existing hydraulic system of the grinding mill, the bladder accumulator set on the rod chamber circuit of the hydraulic cylinder is usually installed on the hydraulic station, which is a certain distance or far away from the hydraulic cylinder. When the thickness of the material bed increases, due to the narrow and long hydraulic circuit, the hydraulic oil in the rod chamber of the hydraulic cylinder cannot enter the accumulator in a short time, resulting in the hydraulic cylinder being unable to respond to the instantaneous change in the thickness of the material bed. The hydraulic oil pressure in the rod chamber of the hydraulic cylinder changes sharply, and the grinding roller produces rigid vibration. When the thickness of the material bed suddenly decreases, since there is no working pressure in the rodless chamber, the grinding roller will directly impact the grinding disc under the action of the pressure of the rod chamber of the hydraulic cylinder, causing the mill to produce impact vibration. All of these have a huge impact on the operating stability of the mill, and it may even stop working.

[0004] For some roller mills with relatively high design capacity, in order to meet the capacity requirements, the nitrogen filling pressure in the bladder accumulator connected to the rod chamber of the hydraulic cylinder needs to match the working pressure required by the rod chamber of the hydraulic cylinder and adapt to a certain working pressure range without adjustment. When the actual production load is insufficient and the mill needs to operate at a capacity lower than the design capacity, such as 60% or below, the working pressure required by the rod chamber of the hydraulic cylinder needs to be further reduced. At this time, the nitrogen filling pressure of the bladder accumulator can no longer adapt to the working pressure required by the new rod chamber of the hydraulic cylinder. It is necessary to shut down and lower the nitrogen filling pressure of the bladder accumulator to match the reduced pressure of the rod chamber of the hydraulic cylinder. At the same time, when the mill needs to operate at a capacity that is seriously lower than the design capacity, such as below 25%, due to the existence of the self-weight of the grinding roller, even if the hydraulic cylinder pressure is set at a lower state, the grinding pressure provided by the grinding roller under the action of the hydraulic cylinder and its own weight exceeds the demand, the grinding roller will frequently impact the grinding disc, and the mill will vibrate and shut down, and it is completely unable to operate normally under low capacity conditions.

[0005] In addition, when the mill encounters an emergency or needs to quickly lift the roller during maintenance, the hydraulic pump station supplies oil to the rodless chamber of the hydraulic cylinder through the oil pump, and the oil in the rod chamber of the hydraulic cylinder flows back to the hydraulic pump station, and the piston rod of the hydraulic cylinder extends to drive the roller to lift up. However, due to the oil supply capacity of the oil pump, the roller is lifted slowly and often cannot be lifted quickly in an emergency.

[0006] In addition, the distances between the hydraulic cylinders of the mill and the hydraulic pump station are different, and the pressure resistance in the hydraulic circuit is different, resulting in slight differences in the circuit flow and pressure of each hydraulic cylinder when the mill is put into production or shut down, and the cylinders move asynchronously. In severe cases, the mill cannot be put into production smoothly or the grinding rollers wear asynchronously, causing great trouble to operation and maintenance. Summary of the invention

[0007] In order to solve the above technical problems, one aspect of the present invention provides a hydraulic loading and adjusting system, which includes at least one hydraulic loading and adjusting unit and a hydraulic control system, and each of the at least one hydraulic loading and adjusting unit includes:

[0008] Hydraulic cylinder;

[0009] A hydraulic pump station, wherein the hydraulic pump station is respectively connected with a rod chamber and a rodless chamber of the hydraulic cylinder;

[0010] A first accumulator connected to a rod chamber of the hydraulic cylinder through a high-pressure hose; and

[0011] The second accumulator is connected to the rodless chamber of the hydraulic cylinder through a high-pressure hose.

[0012] Among them, the hydraulic control system is connected to the hydraulic pump station to control the amount of hydraulic oil provided to the hydraulic cylinder.

[0013] In one embodiment, the first accumulator is a bladder accumulator and the second accumulator is a piston accumulator.

[0014] In one embodiment, the first accumulator and the second accumulator are both disposed close to the hydraulic cylinder.

[0015] In one embodiment, each of the at least one hydraulic loading and adjusting units further includes a first fluid replenishment control valve, which is disposed on a direct-connecting pipe between the rod chamber and the rodless chamber of the hydraulic cylinder, and the first fluid replenishment control valve communicates with the hydraulic control system.

[0016] In one embodiment, the hydraulic loading and adjustment system also includes a second fluid replenishment control valve, which is arranged on a pipeline connected to the hydraulic pump station to transport hydraulic oil to the rod chamber and the rodless chamber in the at least one hydraulic loading and adjustment unit respectively.

[0017] In one embodiment, each of the at least one hydraulic loading and regulating unit further comprises two one-way throttle valves, which are oppositely arranged on a hose for connecting the hydraulic pump station and the rodless chamber of the hydraulic cylinder.

[0018] In one embodiment, the hydraulic loading and adjusting system also includes a first pressure transmitter and a second pressure transmitter, wherein the first pressure transmitter is arranged on a pipeline for connecting the hydraulic pump station with a rod chamber of a hydraulic cylinder in each of at least one hydraulic loading and adjusting unit, and the second pressure transmitter is arranged on a pipeline for connecting the hydraulic pump station with a rodless chamber of a hydraulic cylinder in each of at least one hydraulic loading and adjusting unit, and the first pressure transmitter and the second pressure transmitter communicate with the hydraulic control system respectively.

[0019] Another aspect of the present invention provides a roller mill using the above hydraulic loading and adjustment system, comprising:

[0020] A grinding disc, which can be rotated by the driving device;

[0021] a plurality of grinding rollers, the plurality of grinding rollers being connected to a hydraulic cylinder of a corresponding one of a plurality of hydraulic loading and adjusting units in a hydraulic loading and adjusting system through a rocker arm, and the plurality of grinding rollers being located above the grinding disc; and

[0022] The mill control system includes a hydraulic control system, and the mill control system communicates with the driving device to control the movement of the grinding disc.

[0023] In one embodiment, the grinding roller is connected to the piston rod of the hydraulic cylinder of each of the plurality of hydraulic loading and adjusting units through a rocker arm.

[0024] In one embodiment, the pressure of the rodless chamber of each hydraulic cylinder in the hydraulic loading and adjusting system is between 1.5 MPa and 3 MPa.

[0025] It can be seen from the above description that the roller mill with a hydraulic loading and adjustment system provided by the present invention can dynamically adjust the loading force according to the material characteristics, so as to quickly respond to the changes in the thickness of the material bed during the grinding process of the roller mill, absorb the impact vibration of the material bed when the mill is working, and improve the smooth operation of the mill; by configuring a piston accumulator in the rodless chamber hydraulic circuit of the hydraulic cylinder, the problem that a high-capacity mill cannot work stably under a low-capacity state is solved; in addition, through the configuration of the piston accumulator and the reasonable grinding pressure setting, the mill production capacity can be dynamically adjusted according to the actual load demand without adjusting the nitrogen filling pressure of the rod chamber bladder accumulator, so as to achieve stable production and operation of the mill at low load and improve production efficiency; in maintenance or emergency conditions, the rollers can be lifted quickly to ensure safety and reliability and save maintenance time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic structural diagram of a hydraulic loading and adjusting system according to an exemplary embodiment of the present invention; and

[0027] Figure 2 According to an exemplary embodiment of the present invention, Figure 1 Schematic diagram of the structure of the roller mill with hydraulic loading and adjustment system shown in FIG. DETAILED DESCRIPTION

[0028] The illustrative, non-limiting embodiments of the present invention are described in detail below with reference to the accompanying drawings, and the roller mill with a hydraulic loading and adjustment system according to the present invention is further described.

[0029] Reference Figure 1 The roller mill with a hydraulic loading and adjustment system proposed in the present invention includes a grinding disc 2 and a plurality of grinding rollers 3, and the plurality of grinding rollers 3 are connected to the hydraulic loading and adjustment system through a rocker arm 4, wherein the hydraulic loading and adjustment system includes at least one hydraulic loading and adjustment unit, and each of the at least one hydraulic loading and adjustment unit includes a hydraulic pump station 51, a hydraulic cylinder 52, a first accumulator 53 and a second accumulator 54 to realize hydraulic loading and adjustment.

[0030] The grinding disc 2 is a disc device that can carry the material to be ground and can rotate under the drive of the driving device 1. The size, material, strength, etc. of the grinding disc 2 can be selected by those skilled in the art according to the properties of the material to be ground and the total amount of the material to be ground at a single time, and are not specifically limited here. The driving device 1 can be an electric driving device, a pneumatic driving device, etc., and are not specifically limited here.

[0031] A plurality of grinding rollers 3 are connected to the piston rod of a hydraulic cylinder 52 of a corresponding one of a plurality of hydraulic loading and adjusting units in the hydraulic loading and adjusting system through corresponding rocker arms 4, and the grinding rollers 3 are located above the grinding disc 2 to grind the material on the grinding disc 2 under the action of the hydraulic loading and adjusting system.

[0032] The hydraulic loading and adjustment system includes a plurality of hydraulic loading and adjustment units, each of which is connected to a corresponding one of the plurality of grinding rollers 3 through a rocker arm 4, so as to provide power for the grinding roller 3 to move up and down, and to provide a vibration reduction effect when the material thickness on the grinding disc 2 changes drastically.

[0033] In each hydraulic loading and adjustment unit, the hydraulic pump station 51 is connected to the rod chamber and the rodless chamber of the hydraulic cylinder 52, respectively, to deliver hydraulic oil to the rod chamber and the rodless chamber, respectively. In one embodiment, the hydraulic pump station 51 is connected to the rod chamber and the rodless chamber of the hydraulic cylinder 52 through a steel pipe and a high-pressure hose, that is, the pipeline for connecting the hydraulic pump station 51 and the hydraulic cylinder 52 is composed of a steel pipe and a high-pressure hose in sequence, wherein the high-pressure hose is arranged close to the hydraulic cylinder 52. It should be noted that the hydraulic pump station 51 and the hydraulic cylinder 52 used in the present invention can be any hydraulic pump station 51 and hydraulic cylinder 52 commonly used in the art, and those skilled in the art can select the specifications of the hydraulic pump station 51 and the hydraulic cylinder 52 according to the specific working conditions, and no specific limitation is made here.

[0034] In each hydraulic loading and adjustment unit, the first accumulator 53 is connected to the rod chamber of the hydraulic cylinder 52 through a high-pressure hose, and the second accumulator 54 is connected to the rodless chamber of the hydraulic cylinder 52 through a high-pressure hose. The first accumulator 53 and the second accumulator 54 are used to respectively adjust the hydraulic oil pressure in the rod chamber and the rodless chamber of the hydraulic cylinder 52 and maintain the pressure values ​​of the rod chamber and the rodless chamber so that they do not change drastically, thereby achieving the effect of reducing system vibration.

[0035] It can be seen from the above description that the hydraulic loading and adjustment system proposed in the present invention provides a first accumulator 53 and a second accumulator 54 respectively connected to the rod chamber and the rodless chamber of the hydraulic cylinder 52 in each hydraulic loading and adjustment unit, so that the rod chamber and the rodless chamber of the hydraulic cylinder 52 can quickly exchange hydraulic oil with the first accumulator 53 and the second accumulator 54 respectively, so as to respond to the change of the material thickness on the grinding disc 2, reduce the impact of the grinding roller 3 on the grinding disc 2, and reduce equipment wear.

[0036] Reference Figure 1In one embodiment of the present invention, the first accumulator 53 is a bladder accumulator, and the second accumulator 54 is a piston accumulator. The bladder accumulator is a device composed of, for example, an air charging valve, an air bag, a housing, an oil port, etc. In the process of providing hydraulic oil to the bladder accumulator through the oil port, as the pressure increases, the gas volume decreases, thereby realizing hydraulic energy storage; when the hydraulic oil pressure in the bladder accumulator is lower than the pressure of the nitrogen in the air bag, the volume of the air bag increases, and the accumulator discharges the hydraulic oil under the push of the gas expansion pressure. The bladder accumulator can completely separate the gas from the oil, which can prevent the hydraulic oil from being oxidized, and because the gas inertia is small, the bladder accumulator also has the characteristics of flexible response. Therefore, connecting the rod chamber of the hydraulic oil cylinder 52 to the bladder accumulator through a high-pressure hose can quickly respond to impacts, that is, when the thickness of the material on the grinding disc 2 suddenly increases or decreases, the bladder accumulator can quickly respond accordingly to reduce the impact between the grinding roller 3 and the material on the grinding disc 2. The piston accumulator uses a piston to separate the gas and the hydraulic oil. Due to the existence of the piston's own weight, the piston accumulator has a hysteresis in pressure sensing, but the restriction on the external oil pressure is small, and the oil pressure range that can be adjusted is large. In this way, the rod chamber of the hydraulic cylinder 52 in each hydraulic loading and adjusting unit is connected to the bladder accumulator, which can quickly respond to external impacts; the rodless chamber of the hydraulic cylinder 52 of each hydraulic loading and adjusting unit is connected to the piston accumulator, so that when the pressure output to the outside of the hydraulic loading and adjusting system changes greatly, the pressure of the rodless chamber can be adjusted by the piston accumulator to offset the pressure on the rod chamber side, so that the hydraulic loading and adjusting system can work in a stable range without stopping the mill to adjust the nitrogen filling pressure of the bladder accumulator, thereby improving the working efficiency of the mill and realizing automatic production. For example, when the roller mill is running at low capacity, the working pressure can be stabilized in an applicable range without stopping the mill to adjust the nitrogen filling pressure of the bladder accumulator.

[0037] In one embodiment, in order to improve the exchange efficiency of hydraulic oil between the accumulator and the hydraulic cylinder 52, the first accumulator 53 and the second accumulator 54 are both arranged close to the hydraulic cylinder 52, that is, the length of the hose used to respectively connect the first accumulator 53 and the second accumulator 54 to the hydraulic cylinder 52 is shortened as much as possible when the installation space permits. For example, the length of the hose between the first accumulator 53 and the second accumulator and the hydraulic cylinder 52 is within 1 meter.

[0038] Reference Figure 1, a first replenishment control valve 55 is also installed in each hydraulic loading and adjustment unit, and the first replenishment control valve 55 is set on a hose for connecting the rod chamber and the rodless chamber of the hydraulic cylinder 52. For example, when it is necessary to quickly lift the grinding roller 3 by lifting the piston rod of the hydraulic cylinder 52 (for example, the mill is urgently stopped for safety reasons, foreign objects enter the mill and need to be quickly lifted, or the grinding roller 3 is quickly lifted to the highest position for maintenance), the hydraulic pump station 51 quickly replenishes hydraulic oil to the rodless chamber, and at the same time opens the first replenishment control valve 55 between the rodless chamber and the rod chamber, so that the hydraulic oil in the rod chamber flows into the rodless chamber under the action of the oil pressure difference between the rodless chamber and the rod chamber, thereby further accelerating the extension speed of the piston rod of the hydraulic cylinder 52. In another embodiment of the present invention, the hydraulic loading and adjustment unit includes a second replenishment control valve 59, such as Figure 2 As shown, the second refill control valve 59 is arranged on a pipeline for connecting the hydraulic pump station to transport hydraulic oil to the rod chamber and the rodless chamber in the at least one hydraulic loading and adjusting unit. When it is necessary to quickly lift the grinding roller 3 by lifting the piston rod of the hydraulic oil cylinder 52, the second refill control valve 59 can also be used to quickly balance the hydraulic pressure difference between the rod chamber and the rodless chamber, so that the hydraulic oil in the rod chamber flows into the rodless chamber. It should be noted that in the same hydraulic loading and adjusting system, usually only one of the first refill control valve 55 and the second refill control valve 59 is arranged.

[0039] In one embodiment, each hydraulic loading and adjusting unit further includes two one-way throttle valves 56, which are arranged opposite to each other on a hose for connecting the hydraulic pump station 51 and the rodless chamber of the hydraulic cylinder 52. The two two-way throttle valves 51 can realize two-way control of the hydraulic oil between the hydraulic pump station 51 and the rodless chamber of the hydraulic cylinder 52, that is, the flow of the hydraulic oil in two directions is controlled separately, so as to ensure that the rise and fall of each grinding roller are synchronized, and the lifting speed can be controlled to be fast and the lowering speed can be controlled to be slow. By installing a one-way throttle valve 56 in each hydraulic loading and adjusting unit, the oil pressure flow and pressure resistance in the unit can be controlled, so as to ensure that the actions of each hydraulic cylinder 52 are synchronized.

[0040] Reference Figure 1The hydraulic loading and regulating system further includes a first pressure transmitter 57 and a second pressure transmitter 58. The first pressure transmitter 57 is arranged on a hose for connecting the hydraulic pump station 51 with a rod cavity of at least one hydraulic cylinder 52 in at least one hydraulic loading and regulating unit, and the second pressure transmitter 58 is arranged on a hose for connecting the hydraulic pump station 51 with a rodless cavity of at least one hydraulic cylinder 52 in at least one hydraulic loading and regulating unit, and is used to monitor the oil pressure of all the rod cavity circuits and the rodless cavity circuits in at least one hydraulic loading and regulating unit, respectively, and feed the oil pressure value back to the mill control system, and the mill control system adjusts the specific hydraulic oil pressure in the hydraulic loading and regulating system according to the production capacity of the roller mill. That is to say, during the operation of the mill, the first pressure transmitter 57 and the second pressure transmitter 58 convert the pressure value into an electrical signal in real time and feed it back to the mill control system. The mill control system can adjust and correct the pressure setting value according to the mill production capacity demand - when the pressure of the rod chamber and the rodless chamber of each hydraulic cylinder 52 is lower than the preset value, the mill control system sends a control instruction to the hydraulic pump station 51, and the hydraulic pump station 51 replenishes hydraulic oil to the hydraulic cylinder to increase the pressure until the pressure reaches the preset value and the hydraulic pump station 51 automatically stops working; when the thickness and / or properties of the milled material change, the mill control system can automatically compensate and adjust according to the different preset pressure offsets of the material. It should be noted that the required grinding force is calculated based on the characteristics of the milled material (mainly the grindability index), the output, and the fineness index of the finished product, and then converted to the pressure value of the rod chamber of the hydraulic cylinder 52, and the pressure value is used as the hydraulic oil pressure set by the control system.

[0041] Refer to the following Figure 1 and 2 The working process of the roller mill with hydraulic loading and adjustment system disclosed in the present invention is described.

[0042] The driving device 1 is started to drive the grinding disc 2 to rotate. During the rotation of the grinding disc 2, the material is ground by the pressure of the material applied to the grinding disc 2 by the grinding roller 3. The hydraulic pump station 51 provides hydraulic oil to the rodless chamber of each hydraulic cylinder 52 of the hydraulic loading and adjustment system, so that the rodless chamber of each hydraulic cylinder 52 maintains the initial preset pressure value. For example, the pressure of the rodless chamber of the hydraulic cylinder 52 in each hydraulic loading and adjustment unit is between 1.5mPa-3mPa, so that the material is ground by the pressure of the material applied to the grinding disc 2 by the grinding roller 3 during the rotation of the grinding disc 2. The hydraulic pump station 51 provides hydraulic oil to the rod chamber of each hydraulic cylinder 52, so that the hydraulic cylinder 52 contracts under the action of the hydraulic oil pressure of the rod chamber, and multiple grinding rollers 3 are pressed down to enter a normal grinding state.

[0043] When the material thickness on the grinding disc 2 suddenly decreases, the hydraulic oil in the rodless chamber of each hydraulic cylinder 52 in the hydraulic loading and adjustment system will be pressed into the piston accumulator to increase the pressure in the rodless chamber and slow down the descending speed of the multiple grinding rollers 3; at the same time, the hydraulic oil in the bladder accumulator connected to the rod chamber of each hydraulic cylinder 52 will be replenished into the rod chamber of the corresponding hydraulic cylinder 52 to reduce the pressure in the rod chamber and the downward pressure of the multiple grinding rollers 3, thereby reducing the grinding pressure and the impact of the grinding rollers 3 on the grinding disc 2, thereby achieving a buffering effect and reducing equipment loss. When the material thickness on the grinding disc 2 returns to normal, multiple grinding rollers 3 will rise, and the hydraulic oil in the corresponding piston accumulator connected to the rodless chamber of each hydraulic cylinder 52 will be replenished into the rodless chamber of the corresponding hydraulic cylinder 52, so that the pressure in the rodless chamber is reduced, and the hydraulic oil in the rod chamber of each hydraulic cylinder 52 is re-pressed into the corresponding bladder accumulator, and the pressure in the rodless chamber rises and returns to the preset pressure value, and the pressure under the grinding roller 3 increases accordingly, thereby increasing the grinding pressure, and the mill enters a normal grinding working state.

[0044] When a large-size material passes through or the material thickness suddenly increases, multiple grinding rollers 3 rise, the pressure of the rod chamber of each hydraulic cylinder 52 rises, and the hydraulic oil in the rod chamber quickly enters the bladder accumulator corresponding to the rod chamber under the action of pressure, and multiple grinding rollers 3 are lifted up to relieve the rigid impact of the grinding rollers 3 on the grinding disc 2; at the same time, the hydraulic oil in the corresponding piston accumulator connected to the rodless chamber of each hydraulic cylinder 52 is replenished into the rodless chamber of the corresponding hydraulic cylinder 52. When the thickness of the material bed returns to normal, multiple grinding rollers 3 will drop, and the hydraulic oil in the bladder accumulator will be replenished into the rod chamber of the corresponding hydraulic cylinder 52, so that the pressure of the rod chamber is reduced to the preset pressure value, and the pressure under the grinding roller 3 is reduced accordingly, the grinding pressure returns to the normal value, and the mill enters the normal grinding working state. Subsequently, the hydraulic oil in the rodless chamber of each hydraulic cylinder 52 is re-pressed into the corresponding piston accumulator, and the pressure of the rodless chamber rises and returns to the set value.

[0045] When the mill is under maintenance or in special circumstances and the roller 3 needs to be lifted urgently, the hydraulic loading and regulating system automatically opens the first liquid replenishment control valve 55, and uses the pressure difference between the rod chamber and the rodless chamber of the oil cylinder to allow the hydraulic oil in the rod chamber to directly enter the rodless chamber. When the pressure difference between the rod chamber and the rodless chamber of the hydraulic oil cylinder 52 is lower than the set value, the first liquid replenishment control valve 55 is closed. At the same time, the oil provided by the hydraulic pump will also enter the rodless chamber, causing the oil cylinder piston rod to extend quickly, lifting the roller 3 to a safe height, and ensuring the stability and reliability of the system.

[0046] During the change of the material thickness on the grinding disc 2, the hydraulic pump station 51 is in a non-operating state, and there is no oil exchange between the hydraulic pump station 51 and the hydraulic cylinder 52. The hydraulic oil is only exchanged between the rod chamber of the hydraulic cylinder 52 and the first accumulator 53, and between the rodless chamber and the second accumulator 54 in each hydraulic loading and adjustment unit. Because the first accumulator 53, the second accumulator 54 and the hydraulic cylinder 52 are flexibly connected by a high-pressure hose, the slight swing of the hydraulic cylinder 52 and the impact of the pressure oil will be absorbed by the high-pressure hose, so that the hydraulic circuit has no pressure oil impact and is safe and stable.

[0047] When the actual load is low, that is, when the roller mill is running at low capacity, the pressure value of the rodless chamber of each hydraulic cylinder 52 is increased to offset the working pressure of the rod chamber of the hydraulic cylinder 52 and the dead weight of the grinding roller 3, and the grinding pressure is maintained within a reasonable range to ensure stable and safe operation of the mill without adjusting the nitrogen charging pressure of the bladder accumulator.

Claims

1. A hydraulic loading and adjusting system, comprising at least one hydraulic loading and adjusting unit and a hydraulic control system, wherein each of the at least one hydraulic loading and adjusting unit comprises: Hydraulic cylinder; A hydraulic pump station, wherein the hydraulic pump station is connected to the rod chamber and the rodless chamber of the hydraulic cylinder respectively; a first accumulator connected to a rod chamber of the hydraulic cylinder via a high-pressure hose; and a second accumulator, the second accumulator being connected to the rodless chamber of the hydraulic cylinder through a high-pressure hose, Wherein, the hydraulic control system is connected to the hydraulic pump station to control the amount of hydraulic oil provided to the hydraulic cylinder; Wherein, the first accumulator is a bladder accumulator, and the second accumulator is a piston accumulator; Wherein, each of the at least one hydraulic loading and regulating unit further includes a first fluid replenishment control valve, the first fluid replenishment control valve is arranged on a straight-connecting pipe between a rod chamber and a rodless chamber of the hydraulic cylinder, and the first fluid replenishment control valve communicates with the hydraulic control system; It also includes a second liquid replenishment control valve, which is arranged on a pipeline used to connect the hydraulic pump station to transport hydraulic oil to the rod chamber and the rodless chamber in the at least one hydraulic loading and adjustment unit respectively.

2. The hydraulic loading and adjustment system according to claim 1, wherein: The first accumulator and the second accumulator are both arranged close to the hydraulic cylinder.

3. The hydraulic loading and adjustment system according to claim 1, wherein: Each of the at least one hydraulic loading and adjusting unit further includes two one-way throttle valves, which are oppositely arranged on a hose for connecting the hydraulic pump station and the rodless chamber of the hydraulic cylinder.

4. The hydraulic loading and adjustment system according to claim 1 further includes a first pressure transmitter and a second pressure transmitter, wherein the first pressure transmitter is arranged on a pipeline for connecting the hydraulic pump station with a rod chamber of a hydraulic cylinder in each of the at least one hydraulic loading and adjustment units, and the second pressure transmitter is arranged on a pipeline for connecting the hydraulic pump station with a rodless chamber of a hydraulic cylinder in each of the at least one hydraulic loading and adjustment units, and the first pressure transmitter and the second pressure transmitter communicate with the hydraulic control system respectively.

5. A roller mill using the hydraulic loading and adjustment system according to any one of claims 1 to 4, comprising: A grinding disc, which can be rotated by a driving device; A plurality of grinding rollers, the plurality of grinding rollers are connected to a hydraulic cylinder of a corresponding one of a plurality of hydraulic loading and adjusting units in the hydraulic loading and adjusting system through a rocker arm, and the plurality of grinding rollers are located above the grinding disc; and A mill control system includes the hydraulic control system and communicates with the drive device to control the movement of the grinding disc.

6. The roller mill according to claim 5, wherein: The grinding roller is connected to the piston rod of the hydraulic cylinder of each of the plurality of hydraulic loading and adjusting units through a rocker arm.

7. The roller mill according to claim 5, wherein: The pressure of the rodless chamber of the hydraulic cylinder in each of the hydraulic loading and adjusting systems is between 1.5 MPa and 3 MPa.

Images