A method for reducing tearing of paper machine boots

Abstract

The present invention discloses a method for reducing the tearing of a paper machine boot, and relates to the field of paper machine pressing technology, comprising: collecting the vehicle speed information of the paper machine in real time through a speed sensor, and collecting the oil level information in the boot in real time through a liquid level sensor; comparing the vehicle speed information with a preset vehicle speed threshold; executing the boot pressure boot plate oil injection and the boot boot oil injection control logic according to the comparison result and in combination with a high oil level alarm signal; when a liquid level switch generates a false alarm, the present invention continues the boot plate oil injection according to the change of the vehicle speed, the interval oil injection and the boot boot oil injection remain unchanged, the boot pressure transmission load at different vehicle speeds is interlocked, and the transmission screen increases the torque interlocking setting at the same time, that is, when the vehicle speed reaches a certain speed, the load changes accordingly, which plays a role in controlling the boot pressure roller, and effectively solves the problem that when the liquid level switch generates a false alarm, there is no lubricating oil on the contact surface between the boot and the boot plate, but dry friction occurs, thereby causing the boot to gradually heat up and melt and tear.

Description

Technical Field

[0001] The invention relates to the technical field of paper machine pressing, in particular to a method for reducing the tearing of a paper machine boot. Background Art

[0002] The shoe-type press roll of a paper machine is an important forming and dehydrating equipment in the wet section of a paper machine. The shoe sleeve is a press sleeve specially used for the shoe-type press roll. The press roll of a traditional paper machine has a narrow nip area. When the line pressure is increased, the concentrated pressure easily causes the paper sheet to collapse, which limits the dehydration of the paper sheet. The large-diameter press roll increases the nip width to a certain extent, which can appropriately increase the line pressure, but it still cannot meet the requirements of high-speed paper machines.

[0003] The existing boot pressure and boot plate oil injection control logic: (1) When the vehicle speed is ≤425m / min, and there is no alarm for the high oil level in the boot sleeve, the boot plate oil injection continues; (2) When the vehicle speed is ≤425m / min, and there is an alarm for the high oil level in the boot sleeve, the boot plate oil injection is turned off; (3) When the vehicle speed is >425m / min, regardless of whether there is a high oil level alarm in the boot sleeve, the boot plate oil injection continues. Boot sleeve oil injection control logic: (1) When the vehicle speed is ≤150m / min, regardless of whether there is a high oil level alarm in the boot sleeve, the boot sleeve oil injection is turned off; (2) When the vehicle speed is >150m / min, and there is an alarm for the high oil level in the boot sleeve, the boot sleeve oil injection is turned off; (3) When the vehicle speed is >150m / min, and there is a high oil level alarm in the boot sleeve but no alarm, the oil injection continues. Under the above original control logic of the shoe plate oil injection and the shoe sleeve oil injection, when the vehicle speed is ≤425m / min, if the liquid level switch generates a false alarm (high liquid level alarm), the shoe sleeve oil injection and the shoe plate oil injection will be turned off at the same time, and the oil pump inside the shoe sleeve will be turned on at the same time and continue to work until the liquid level alarm disappears. In this case, the lubricating oil inside the shoe sleeve is quickly pumped away by the oil pump, and the contact surface between the shoe sleeve and the shoe plate has no lubricating oil and dry friction, which causes the shoe sleeve to gradually heat up and melt and tear; based on the above shortcomings, the present invention proposes a method for reducing the tearing of the paper machine shoe sleeve. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a method for reducing the tearing of the shoe cover of a papermaking machine, which solves the problem that when the liquid level switch generates a false alarm (high liquid level alarm), the contact surface between the shoe cover and the shoe plate is dry rubbed without lubricating oil, thereby causing the shoe cover to gradually heat up and melt and tear; when the liquid level switch generates a false alarm (high liquid level alarm), the shoe plate sprays oil continuously according to the change of vehicle speed, the interval spraying oil and the shoe cover spraying oil remain unchanged, the load at different vehicle speeds of the shoe pressure transmission is interlocked, and the transmission screen increases the torque interlocking setting. At a certain speed, the load change can control the shoe pressure roller, so as to avoid the contact surface between the shoe cover and the shoe plate being dry rubbed without lubricating oil, and the shoe cover gradually heating up and melting and tearing.

[0005] To achieve the above object, according to an embodiment of the first aspect of the present invention, a method for reducing the tearing of a shoe cover of a paper machine is provided, comprising the following steps:

[0006] Step 1: The speed information of the paper machine is collected in real time through the speed sensor and marked as Vt, and the oil level information in the boot is collected in real time through the liquid level sensor and marked as Lt;

[0007] Compare the oil level information Lt with the preset oil level threshold; if Lt>the preset oil level threshold, generate a high oil level alarm signal;

[0008] Step 2: Compare the vehicle speed information Vt with the preset vehicle speed threshold; execute the shoe pressure shoe plate injection control logic and the shoe sleeve injection control logic according to the comparison result and in combination with the high oil level alarm signal; wherein the preset vehicle speed threshold is 150m / min;

[0009] Step 3: When the high oil level alarm in the boot appears, the boot pressure transmission load at different vehicle speeds is interlocked, and the transmission screen adds torque interlocking settings, that is, when the vehicle speed Vt reaches a certain speed, the load changes accordingly.

[0010] Furthermore, the shoe pressure shoe plate injection control logic is specifically manifested as follows:

[0011] When Vt≤150m / min and there is no high oil level alarm in the boot sleeve, the boot pressure plate will continue to spray oil;

[0012] When Vt≤150m / min, and there is a high oil level alarm in the boot, first turn off the oil injection for 120 seconds, then turn on the oil injection for 15 seconds, then turn off the oil injection for 120 seconds, then turn on the oil injection for 15 seconds, repeat the above actions until the high oil level alarm disappears and then continue to inject oil;

[0013] When Vt>150m / min, fuel injection will continue regardless of whether there is a high oil level alarm.

[0014] Furthermore, the boot oil injection control logic is specifically expressed as follows:

[0015] When Vt≤150m / min, no matter there is a high oil level alarm in the boot, the boot oil spraying shall be closed;

[0016] When Vt>150m / min and there is a high oil level alarm in the boot, turn off the boot spray;

[0017] When Vt>150m / min and there is no high oil level alarm in the boot, continue to spray oil.

[0018] Furthermore, the torque interlocking setting specifically includes:

[0019] When the vehicle speed is in the creeping state, the torque alarm value is set to the provisional value * 12%, with a delay of 5S; the trip value is set to the provisional value * 15%, with a delay of 10S; the provisional value is pre-set by the administrator;

[0020] When the vehicle speed Vt≤150m / min, the torque alarm value is set to the provisional value*15%, with a delay of 5S; the trip value is set to the provisional value*20%, with a delay of 10S;

[0021] When the vehicle speed Vt>150m / min, the torque alarm value is set to the temporary value*60%, with a delay of 10S; the trip value is set to the temporary value*70%, with a delay of 15S.

[0022] Furthermore, the method further comprises:

[0023] When the high oil level alarm in the boot lasts for more than the preset value of 6 minutes, a liquid level switch failure or oil pumping failure alarm message is issued, where the preset value is pre-set by the administrator.

[0024] Furthermore, the method further comprises:

[0025] When the high oil level alarm in the boot sleeve lasts for more than the preset value of 10 minutes, the chain will trip.

[0026] Furthermore, the method further comprises:

[0027] An alarm light is installed on the DCS operation box. When the oil level Lt in the boot is greater than the preset oil level threshold or any temperature in the boot is higher than 80 degrees Celsius, the alarm light will sound an alarm.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] When the liquid level switch generates a false alarm (high liquid level alarm), the present invention controls the shoe plate to continue to spray oil according to the change of vehicle speed, the intermittent spraying and the shoe sleeve spraying remain unchanged, and the load of the shoe pressure transmission at different vehicle speeds is interlocked. At the same time, the transmission screen increases the torque interlocking setting; when the vehicle speed Vt reaches a certain speed, the load changes accordingly, which can control the shoe pressure roller, thereby avoiding dry friction between the contact surface of the boot sleeve and the shoe plate due to the absence of lubricating oil, thereby causing the boot sleeve to gradually heat up and melt and tear. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1The present invention is a principle block diagram of a method for reducing tearing of a paper machine boot. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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.

[0033] like Figure 1 As shown, a method for reducing tearing of a paper machine boot comprises the following steps:

[0034] Step 1: The speed information of the paper machine is collected in real time through the speed sensor and marked as Vt, and the oil level information in the boot is collected in real time through the liquid level sensor and marked as Lt;

[0035] Compare the oil level information Lt with the preset oil level threshold; if Lt>the preset oil level threshold, generate a high oil level alarm signal;

[0036] Step 2: Compare the vehicle speed information Vt with the preset vehicle speed threshold; execute the shoe pressure plate injection control logic and the shoe cover injection control logic according to the comparison result; the preset vehicle speed threshold is 150m / min;

[0037] Among them, the shoe pressure shoe plate injection control logic is specifically manifested as follows:

[0038] When Vt≤150m / min and there is no high oil level alarm in the boot sleeve, the boot pressure plate will continue to spray oil;

[0039] When Vt≤150m / min, and there is a high oil level alarm in the boot, first turn off the oil injection for 120 seconds, then turn on the oil injection for 15 seconds, then turn off the oil injection for 120 seconds, then turn on the oil injection for 15 seconds, repeat the above actions until the high oil level alarm disappears and then continue to inject oil;

[0040] When Vt>150m / min, fuel injection will continue regardless of whether there is a high oil level alarm;

[0041] Among them, the boot injection control logic is specifically manifested as follows:

[0042] When Vt≤150m / min, no matter there is a high oil level alarm in the boot, the boot oil spraying shall be closed;

[0043] When Vt>150m / min and there is a high oil level alarm in the boot, turn off the boot spray;

[0044] When Vt>150m / min and there is no high oil level alarm in the boot, continue to spray oil;

[0045] Step 3: When the high oil level alarm in the boot appears, the boot pressure transmission load at different vehicle speeds is interlocked, and the transmission screen adds torque interlock settings; the specific settings include:

[0046] When the vehicle speed is in the creeping state, the torque alarm value is set to the provisional value * 12%, with a delay of 5S; the trip value is set to the provisional value * 15%, with a delay of 10S; the provisional value is pre-set by the administrator;

[0047] When the vehicle speed Vt≤150m / min, the torque alarm value is set to the provisional value*15%, with a delay of 5S; the trip value is set to the provisional value*20%, with a delay of 10S;

[0048] When the vehicle speed Vt>150m / min, the torque alarm value is set to the provisional value*60%, with a delay of 10S; the trip value is set to the provisional value*70%, with a delay of 15S;

[0049] In this embodiment, when the vehicle speed Vt reaches a certain speed, the load changes accordingly, and the shoe pressure roller can be controlled, so that the contact surface between the shoe cover and the shoe plate can be prevented from dry friction due to the absence of lubricating oil, and the shoe cover gradually heats up and melts and tears;

[0050] Step 4: When the high oil level alarm in the boot lasts for more than the preset value of 6 minutes, the liquid level switch failure or oil pumping failure alarm information is issued; when the high oil level alarm in the boot lasts for more than the preset value of 10 minutes, the chain trips; the preset value is pre-set by the administrator;

[0051] The method further includes: installing an alarm light on the DCS operation box, and when the oil level Lt in the boot sleeve is greater than a preset oil level threshold or any temperature in the boot sleeve is higher than 80 degrees Celsius, the alarm light sounds an alarm;

[0052] In this embodiment, an alarm output is added to the logic. The optimized logic can effectively prevent the shoe cover from being torn due to the failure of the liquid level switch to spray oil when the high liquid level alarm is triggered;

[0053] In this embodiment, the problem that when the liquid level switch generates a false alarm (high liquid level alarm), there is no lubricating oil on the contact surface between the boot cover and the boot plate and dry friction occurs, which causes the boot cover to gradually heat up and melt and tear. When the liquid level switch generates a false alarm (high liquid level alarm), the boot plate continues to spray oil according to the change of vehicle speed, the oil spraying and the boot cover oil spraying remain unchanged, and the load of the boot pressure transmission at different vehicle speeds is interlocked, and the transmission screen adds a torque interlocking setting. When the vehicle speed Vt reaches a certain speed, the load changes accordingly, which can control the boot pressure roller, thereby avoiding the problem that there is no lubricating oil on the contact surface between the boot cover and the boot plate and dry friction occurs, which causes the boot cover to gradually heat up and melt and tear.

[0054] The working principle of the present invention is:

[0055] A method for reducing the tearing of a boot cover of a papermaking machine. During operation, the vehicle speed information of the papermaking machine is collected in real time through a speed sensor and marked as Vt, and the oil level information in the boot cover is collected in real time through a liquid level sensor and marked as Lt; if Lt> a preset oil level threshold, a high oil level alarm signal is generated; the vehicle speed information Vt is compared with the preset vehicle speed threshold; the boot pressure boot plate oil injection control logic and the boot cover oil injection control logic are executed according to the comparison result; wherein the boot pressure boot plate oil injection control logic is: when Vt≤150m / min, and there is no high oil level alarm in the boot cover, the boot pressure boot plate continues to spray oil; when Vt≤150m / min, and there is a high oil level alarm in the boot cover, the oil injection is first turned off for 120 seconds and then turned on for 15 seconds, and then the oil injection is turned off for 120 seconds and then turned on for 15 seconds, and the above actions are repeated until the high oil level alarm disappears and then the oil injection is continued; when Vt>150m / min, regardless of whether there is a high oil level alarm, the oil injection is continued Oil; the boot sleeve oil injection control logic is: when Vt≤150m / min, regardless of whether there is a high oil level alarm in the boot sleeve, the boot sleeve oil injection is turned off; when Vt>150m / min, and there is a high oil level alarm in the boot sleeve, the boot sleeve oil injection is turned off; when Vt>150m / min, and there is no high oil level alarm in the boot sleeve, the oil injection is continued; when the high oil level alarm in the boot sleeve occurs, the load at different vehicle speeds of the boot pressure transmission is interlocked, and the transmission screen adds a torque interlock setting; when the liquid level switch generates a false alarm (high liquid level alarm), the present invention continues to spray oil on the boot plate according to the change of vehicle speed, the interval spraying and the boot sleeve oil injection remain unchanged, the load at different vehicle speeds of the boot pressure transmission is interlocked, and the transmission screen adds a torque interlock setting; when the vehicle speed Vt reaches a certain speed, the load changes accordingly, and the boot pressure roller can be controlled, so as to avoid dry friction between the contact surface of the boot sleeve and the boot plate without lubricating oil, thereby causing the boot sleeve to gradually heat up and melt and tear.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0057] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for reducing tearing of paper machine boots, characterized in that: The steps include: Step 1: The speed information of the paper machine is collected in real time through the speed sensor and marked as Vt, and the oil level information in the boot is collected in real time through the liquid level sensor and marked as Lt; Compare the oil level information Lt with the preset oil level threshold; if Lt>the preset oil level threshold, generate a high oil level alarm signal; Step 2: Compare the vehicle speed information Vt with the preset vehicle speed threshold; execute the shoe pressure shoe plate injection control logic and the shoe sleeve injection control logic according to the comparison result and in combination with the high oil level alarm signal; wherein the preset vehicle speed threshold is 150m / min; Among them, the shoe pressure shoe plate injection control logic is specifically manifested as follows: When Vt≤150m / min and there is no high oil level alarm in the boot sleeve, the boot pressure plate will continue to spray oil; When Vt≤150m / min, and there is a high oil level alarm in the boot, first turn off the oil injection for 120 seconds, then turn on the oil injection for 15 seconds, then turn off the oil injection for 120 seconds, then turn on the oil injection for 15 seconds, repeat the above actions until the high oil level alarm disappears and then continue to inject oil; When Vt>150m / min, fuel injection will continue regardless of whether there is a high oil level alarm; Among them, the boot injection control logic is specifically manifested as follows: When Vt≤150m / min, no matter there is a high oil level alarm in the boot, the boot oil spraying shall be closed; When Vt>150m / min and there is a high oil level alarm in the boot, turn off the boot spray; When Vt>150m / min and there is no high oil level alarm in the boot, continue to spray oil; Step 3: When the high oil level alarm in the boot appears, the boot pressure transmission load at different vehicle speeds is interlocked, that is, when the vehicle speed Vt reaches a certain speed, the load changes accordingly; at the same time, the transmission screen adds torque interlocking settings; among which, the torque interlocking settings specifically include: When the vehicle speed is in the creeping state, the torque alarm value is set to the provisional value*12%, with a delay of 5S; the trip value is set to the provisional value*15%, with a delay of 10S; the provisional value is pre-set by the administrator; When the vehicle speed Vt≤150m / min, the torque alarm value is set to the provisional value*15%, with a delay of 5S; the trip value is set to the provisional value*20%, with a delay of 10S; When the vehicle speed Vt>150m / min, the torque alarm value is set to the temporary value*60%, with a delay of 10S; the trip value is set to the temporary value*70%, with a delay of 15S.

2. A method for reducing tearing of paper machine boots according to claim 1, characterized in that: in, The method also includes: when the high oil level alarm duration in the boot exceeds a preset value of 6 minutes, a liquid level switch failure or oil pumping failure alarm message is issued, wherein the preset value is pre-set by an administrator.

3. A method for reducing tearing of paper machine boots according to claim 2, characterized in that: in, The method also includes: when the duration of the high oil level alarm in the boot sleeve exceeds a preset value of 10 minutes, the chain tripping is performed.

4. A method for reducing tearing of paper machine boots according to claim 1, characterized in that: in, The method further includes: installing an alarm light on the DCS operation box, and when the oil level Lt in the boot sleeve is greater than a preset oil level threshold or any temperature in the boot sleeve is higher than 80 degrees Celsius, the alarm light sounds an alarm.

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