CN110673546B - Control method for realizing high-precision fixed-length shearing of rotary flying shear - Google Patents
Control method for realizing high-precision fixed-length shearing of rotary flying shear Download PDFInfo
- Publication number
- CN110673546B CN110673546B CN201910939774.3A CN201910939774A CN110673546B CN 110673546 B CN110673546 B CN 110673546B CN 201910939774 A CN201910939774 A CN 201910939774A CN 110673546 B CN110673546 B CN 110673546B
- Authority
- CN
- China
- Prior art keywords
- shearing
- angle
- shear
- flying shear
- flying
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
- G05B19/416—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control of velocity, acceleration or deceleration
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
- B23D25/00—Machines or arrangements for shearing stock while the latter is travelling otherwise than in the direction of the cut
- B23D25/02—Flying shearing machines
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/32—Operator till task planning
- G05B2219/32063—Adapt speed of tool as function of deviation from target rate of workpieces
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Human Computer Interaction (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Control Of Metal Rolling (AREA)
Abstract
A control method for realizing high-precision fixed-length shearing of a rotary flying shear comprises the following steps: calculating the shearing angle of the flying shear, and determining the non-shearing angle of the flying shear according to the shearing angle of the flying shear; calculating the acceleration of the flying shear blade in the non-shearing angle according to the shearing length set value, the actual linear speed of the strip steel, the rotating radius of the shear blade and the shearing angle; calculating the distance value from the next shearing point to the flying shear through the measuring roller; calculating the speed set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the cutting edge of the flying shear in the non-shearing angle area; calculating the angle set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the speed set value of the cutting edge of the flying shear in the non-shearing angle area; and carrying out closed-loop control on the position of the cutting edge of the flying shear according to the set value and the actual angle of the cutting edge of the flying shear.
Description
Technical Field
The invention belongs to the technical field of industrial control, and particularly relates to a control method for realizing high-precision fixed-length shearing of a rotary flying shear.
Background
Under the condition of ensuring the normal operation of the production line, the shearing of the continuous material can be realized by controlling the shearing edge of the flying shear to be at the same speed as the production line. Due to the high-efficiency working mode, the flying shear becomes one of the extremely important large-scale equipment in the metallurgy field, particularly in the strip steel production field, can be applied to continuous rolling lines of a pickling and rolling combined unit and the like, and can also be applied to an independent transverse cutting unit, a continuous annealing unit, a continuous galvanizing unit and a continuous electrotinning unit, and can shear the head and the tail of a strip or shear the strip steel into a fixed length.
The common flying shear forms are mainly as follows: rocker, pendulum, crank, and rotary, etc. Wherein, the shearing precision of the rotary flying shear is up to +/-1 mm, the highest shearing speed is up to 200m/min, and the maximum shearing frequency can be up to 180 times/min. Therefore, the rotary flying shear is applied to production lines with fast production rhythm and high shearing precision requirements.
No matter what structure form of rotary flying shears, the basic working principle is that the motor drives the shear blades to do circular motion through the gearbox, the running track of the shear blades in the shearing process is an approximate circle, as shown in fig. 3, the flying shears rotate for a circle, when the upper shear blade is at the lowest point, the lower shear blade is at the highest point, and the upper shear blade and the lower shear blade are mutually staggered to thoroughly shear the strip steel. The completely staggered position of the upper and lower cutting edges of the flying shear, namely the lowest point of the upper cutting edge, is called as a shearing point of the flying shear, the cutting edge angle of the flying shear is artificially marked as 0 degree when the flying shear passes through the shearing point every time, and the cutting edge angle is changed from 0 degree to 360 degrees when the flying shear finishes shearing every time.
Fixed length cutting is a very important control function of flying shears. In the fixed-length shearing process, the strip steel runs at a certain fixed speed, the flying shears continuously rotate at a speed set by a program, and when the strip steel rotates 360 degrees, the strip steel is sheared into a piece, and the length value of the piece is in direct relation with the rotating speed of the flying shears. Referring to fig. 2, a measuring roll is generally arranged in front of the flying shears for calculating the actual speed and the shearing length of the strip steel.
Disclosure of Invention
In order to improve the shearing precision of the flying shears, the invention provides a control method for realizing the high-precision fixed-length shearing of the rotary flying shears, which has the following specific scheme:
a control method for realizing high-precision fixed-length shearing of a rotary flying shear comprises the following steps:
calculating the shearing angle of the flying shear, and determining the non-shearing angle of the flying shear according to the shearing angle of the flying shear;
calculating the acceleration of the flying shear blade in the non-shearing angle according to the shearing length set value, the actual linear speed of the strip steel, the rotating radius of the shear blade and the shearing angle;
calculating the distance value from the next shearing point to the flying shear through the measuring roller;
calculating the speed set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the cutting edge of the flying shear in the non-shearing angle area;
calculating the angle set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the speed set value of the cutting edge of the flying shear in the non-shearing angle area;
and carrying out closed-loop control on the position of the cutting edge of the flying shear according to the set value and the actual angle of the cutting edge of the flying shear.
Further, calculating a shearing angle of the flying shear, and determining a non-shearing angle area of the flying shear according to the shearing angle of the flying shear specifically comprises:
because the cutting edge contacts the strip steel only in a certain angle range around the shearing point of the flying shear, namely, the left side and the right side of the shearing point of the flying shear are respectively provided with a contact angle which is a shearing angle, the size of the shearing angle is related to the coincidence quantity between the upper cutting edge and the lower cutting edge of the flying shear, the thickness of the strip steel and the rotating radius of the cutting edge of the flying shear, and the calculation formula is as follows:
in the formula: alpha is a shear angle; r is the rotating radius of the shear blade; MD is the thickness of the strip steel; MU is the overlapping amount between the upper and lower shear blades;
and in the non-shearing angle area, namely the area where the shearing edge does not contact the strip steel, after the shearing angle alpha is calculated, the range of the non-shearing angle area is alpha to (360-alpha).
Further, the method further comprises: dividing a rotating circle of a cutting edge of the flying shear into three areas, namely a rear cutting angle area, a non-cutting angle area and a front cutting angle area by taking a cutting angle as a boundary, wherein the rear cutting angle area is an area between a cutting edge and a strip steel separation area from a cutting point of the flying shear to the preparation of the cutting edge after the cutting is finished; a non-shearing angle area, namely an area where the shearing edge does not contact the strip steel, wherein the shearing edge and the strip steel are completely separated in the area; the front shearing angle area is the area between the cutting edge of the flying shears and the shearing point of the flying shears when the strip steel comes into contact with the cutting edge of the flying shears.
Further, the method further comprises: and calculating the speed set values and the acceleration set values of the flying shear blades in the front shear angle area and the rear shear angle area according to the actual angle values of the shear blades and the actual speed values of the strip steel.
Further, the calculation of the speed set values and the acceleration set values of the flying shear blades in the front shear angle area and the rear shear angle area according to the actual angle value of the shear blade and the actual speed value of the strip steel is specifically as follows:
because the strip steel runs in the horizontal direction, the flying shear blades rotate along the circular arc, the speeds of the strip steel and the flying shear blades are kept consistent in the shearing angle, and then the set speed of the flying shear in the shearing area is calculated as follows:
v1=v3=V/(cosθ);
in the formula: v. of1Setting the flying shear speed in the rear shear angle; v. of3Setting the flying shear speed in the front shear angle; v is the actual linear speed of the strip steel; theta is a flying shear angle and satisfies 0<θ<Alpha or 360-alpha<θ<360(α is the shear angle).
The acceleration set value of the flying shear in the shearing area is as follows:
in the formula: a is1Setting the flying shear acceleration in the rear shear angle; a is3Setting the flying shear acceleration in the front shear angle; v is the actual linear speed of the strip steel; theta is a flying shear angle and satisfies 0<θ<Alpha or 360-alpha<θ<360(α is the shear angle); and R is the rotating radius of the cutting edge.
Further, calculating the acceleration of the flying shear blade in the non-shearing angle according to the shearing length set value, the actual linear speed of the strip steel, the rotating radius of the shear blade and the shearing angle specifically comprises the following steps:
in the fixed-length shearing process, when the strip steel keeps the running distance of the speed V as the shearing set length L, the running length of the flying shear is 2 pi R;
when the shearing set length L is less than or equal to 2 pi R x (2-alpha/180), the flying shears decelerate first and then accelerate or accelerate first and then decelerate, the middle does not need to stop, the acceleration and deceleration switching point is at the T/2 time of single fixed-length shearing, the acceleration is switched from A to-A, and the calculation formula is as follows:
t1=t2=T/2;
when the shearing set length L is more than 2 pi R x (2-alpha/180), the flying shear is decelerated to stop firstly, and then accelerated after a period of time, and the acceleration is t1Is switched from A to 0 at t2Is switched from 0 to-A, t1、t2The calculation formula for A is as follows:
in the formula, L is a set value of the shearing length; v is the actual linear speed of the strip steel; r is the rotating radius of the shear blade; alpha is a shear angle; t (L/V) is used for single fixed-length cutting; a is the acceleration of the flying shear; t is t1Switching time points for the first acceleration in a non-shearing angle area; t is t2The second acceleration switching time point is in the non-shear angle region.
Further, the distance value from the next shearing point to the flying shear is calculated through the measuring roller, and specifically:
the measuring roll is arranged at the strip steel in front of the flying shear, when the cutting edge of the flying shear passes through the cutting point of the flying shear, the counting value of the encoder of the measuring roll is reset, the accumulated value of the coded pulses of the measuring roll is used for calculating the distance value from the next cutting point to the flying shear, and the calculation formula is as follows:
in the formula, l' is the distance value from the next shearing point to the flying shear; l is a set value of the shearing length; i is1Encoding the pulse integration value for the measuring roll; d1To measure roll diameter; i.e. i1For measuring the gear box transformation ratio of the roller; n is1The number of pulses per revolution is measured for the roller encoder.
Further, the specific calculation of the speed set value of the flying shear blade in the non-shearing angle region according to the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the flying shear blade in the non-shearing angle is as follows:
the used time t ' ═ L ')/V of the fixed-length shearing can be calculated according to the distance value L ' from the next shearing point of the strip steel to the flying shears, wherein L is the set value of the shearing length; v is the actual speed of the strip steel, and the calculation formula of the speed set value of the flying shear obtained by combining the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the cutting edge of the flying shear in the non-shearing angle is as follows:
in the formula, v2Setting the flying shear speed in a non-shearing angle; a is the acceleration of the flying shear; l' is the distance value from the next shearing point to the flying shear; r is the rotating radius of the shear blade; alpha is a shear angle; v is the actual linear speed of the strip steel; l is the setting of the shearing length; t' is the time used for the fixed-length cutting;the time taken for the flying shear to rotate through the shear angle; t is t1A first speed switching time point in a non-shearing angle area; t is t2A second speed switching time point for the non-shear angle region; t (═ L/V) is used for single fixed length cutting.
Further, the specific angle setting of the flying shear blade in the non-shearing angle area is calculated according to the distance value from the next shearing point of the strip steel to the flying shear:
the calculation formula of the angle set value of the flying shear blade in the non-shearing angle area is obtained by combining the distance value from the next shearing point of the strip steel to the flying shear and the speed set value of the flying shear blade in the non-shearing angle area, and is as follows:
in the formula, theta is a set value of the flying shear angle and satisfies alpha<θ<360-alpha; l is the setting of the shearing length; l' is the distance value from the next shearing point to the flying shear; a is the acceleration of the flying shear; r is the rotating radius of the shear blade; alpha is a shear angle; v is the actual linear speed of the strip steel; t' is the time spent in the fixed-length shearing; t "is the time taken for the flying shear to rotate through the shear angle; t is t1A first speed switching time point in a non-shearing angle area; t is t2A second speed switching time point for the non-shear angle region; t (═ L/V) is used for single fixed length cutting.
And further, carrying out closed-loop control on the position of the cutting edge of the flying shear according to the set value and the actual angle of the cutting edge of the flying shear.
The invention has the following beneficial effects:
1. according to the method, the shearing angle is calculated through parameters such as the thickness of the strip steel and the weight of the shearing edge, the time points of steel biting and steel removing of the shearing edge are accurately judged, the working process of the shearing edge is divided into three parts, and speed control is respectively carried out, so that the speed control precision of the flying shear is greatly improved;
2. in the shearing angle, the speed set value of the flying shears is calculated by directly utilizing the actual speed of the strip steel and the flying shear angle, the calculation error rate is basically 0, the strip steel cutting edge accident caused by the error speed set of the flying shears is effectively avoided, the cutting edge is protected, and the fault rate is reduced;
3. the invention provides a method for calculating a set value of the flying shear speed by using the distance value of the next shearing point in a non-shearing area, which fully considers the mechanical characteristics of flying shear equipment, avoids the violent acceleration and deceleration of a motor, and effectively protects the flying shear equipment on the basis of improving the speed control precision;
4. on the basis of calculating the speed set value of the flying shear in the non-shearing area according to the distance value of the next shearing point, the angle closed-loop control of the shearing edge is added, the flying shear speed control lag caused by the calculation method is effectively avoided, the angle control precision of the flying shear in the area is improved, and the fixed-length shearing control precision of the flying shear is further effectively improved.
Drawings
FIG. 1 is a flowchart of a control method for implementing high-precision fixed-length shearing of a rotary flying shear according to an embodiment of the present invention
FIG. 2 is a schematic diagram of the arrangement of the rotary flying shear fixed-length shearing related equipment;
FIG. 3 is a schematic diagram of the movement track of the cutting edge of the rotary flying shear during the fixed-length cutting process;
FIG. 4 is a schematic diagram showing the relationship among the distance value from the next cutting point to the flying shear, the cutting edge angle and the cutting edge speed in the fixed-length cutting process;
FIG. 5 is a schematic diagram of a set speed curve of the flying shear during fixed-length shearing without stopping;
FIG. 6 is a diagram illustrating a set curve of the flying shear speed when the cutting needs to be stopped during the fixed-length cutting process;
fig. 7 is a schematic flow chart of the flying shear fixed-length shearing control.
Wherein V is the actual linear speed of the strip steel; v is the flying shear speed setting; alpha is a shear angle; v. of1Setting the flying shear speed in the rear shear angle; v. of2Setting the flying shear speed in a non-shearing area; v. of3Setting the flying shear speed in the front shear angle; l is the setting of the shearing length; l' is the distance value from the next shearing point to the flying shear; theta 'is a flying shear angle value when the distance value of the next shearing point in the fixed-length shearing process is l'; v 'is the speed setting of the flying shear when the distance value of the next shearing point in the fixed-length shearing process is l'; t 'is a time value when the distance value of the next shearing point in the fixed-length shearing process is l'; t' is the time value of the flying shear rotating through the shearing angle; t is the time for single fixed-length shearing; t is t1Switching time point for the first speed of non-shearing area; t is t2The second speed switching time point is the non-cutting area.
In FIG. 3, phi is a post-shear corner region; ② a non-shearing area; and thirdly, a front shearing angle area.
FIG. 5 is a view showing the area of the shadow (r) in FIG. 6 corresponding to the arc length of the region (r) in FIG. 3; FIG. 5 is a view showing the hatched area (II) in FIG. 6 corresponding to the arc length of the region (II) in FIG. 3; FIG. 5 is a view showing a shadow area (c) in FIG. 6 corresponding to a length of an arc of the area (c) in FIG. 3; in fig. 5 and 6, the area (r) + (r) is equal to the cutting length setting value L.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
During normal production, the cutting edge of the rotary flying shear stops at a certain fixed angle, when the cutting point on the strip steel reaches a set position, the strip steel enters a cutting starting process, the strip steel runs at a fixed speed V, the flying shear is started from the stop angle and accelerated to the same speed as the strip steel and then passes through the cutting point, the first cutting is completed, as shown in fig. 2, and then the fixed-length cutting process is started.
As shown in fig. 4, in the fixed-length shearing process, the strip shearing length L is constant, the strip running speed V is constant, the fixed-length shearing time T is constant, and T is L/V. The completely staggered position of the upper and lower cutting edges of the flying shear, namely the lowest point of the upper cutting edge, is called as the shearing point of the flying shear, the cutting edge angle of the flying shear is artificially marked as 0 degree when passing through the shearing point every time, so that the cutting edge angle of the flying shear is changed from 0 degree to 360 degrees when the flying shear completes one shearing, as shown in figure 3, and the speed of the flying shear reaches the running speed V of the strip steel when the fixed-length shearing starts and ends each time.
In conclusion, the analysis shows that in the fixed-length shearing process, the flying shear speed V is controlled to run from 0 degree to 360 degrees in the T time when the strip runs at the speed V, and the flying shear speed is ensured to be V at the beginning and the end of the fixed-length shearing process.
Based on the principle, as shown in fig. 1, as a first embodiment of the present invention, there is provided a control method for realizing high-precision fixed-length cutting of a rotary flying shear, the method including:
calculating the shearing angle of the flying shear, and determining the non-shearing angle of the flying shear according to the shearing angle of the flying shear;
calculating the acceleration of the flying shear blade in the non-shearing angle according to the shearing length set value, the actual linear speed of the strip steel, the rotating radius of the shear blade and the shearing angle;
calculating the distance value from the next shearing point to the flying shear through the measuring roller;
calculating the speed set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the cutting edge of the flying shear in the non-shearing angle area;
calculating the angle set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the speed set value of the cutting edge of the flying shear in the non-shearing angle area;
and carrying out closed-loop control on the position of the cutting edge of the flying shear according to the set value and the actual angle of the cutting edge of the flying shear.
Wherein, calculating the shearing angle of the flying shear, and determining the non-shearing angle area of the flying shear according to the shearing angle of the flying shear specifically comprises the following steps:
when the flying shear shears the strip steel, in order to ensure the safety of the shear blade and simultaneously not cause damage to the strip steel, the speed of the flying shear in the process of contacting the strip steel is kept consistent, because the shear blade only contacts the strip steel within a certain angle range around a shearing point, namely, a contact angle is respectively arranged around a vertical shearing point, the contact angle is a shearing angle, the size of the shearing angle is related to the coincidence quantity between the upper shear blade and the lower shear blade of the flying shear, the thickness of the strip steel and the rotating radius of the shear blade of the flying shear, and the calculation formula is as follows:
in the formula: alpha is a shear angle; r is the rotating radius of the shear blade; MD is the thickness of the strip steel; MU is the overlapping amount between the upper and lower shear blades;
and in the non-shearing angle area, namely the area where the shearing edge does not contact the strip steel, after the shearing angle alpha is calculated, the range of the non-shearing angle area is alpha to (360-alpha).
Preferably, the method further comprises:
dividing a rotating circle of a cutting edge of the flying shear into three areas by taking a shearing angle as a boundary, wherein the first area is a rear shearing angle area, namely an area between the cutting edge preparation and strip steel separation after the cutting edge is cut from a shearing point of the flying shear, and the cutting edge speed and the strip steel speed are kept consistent or even slightly advanced in the area; the area II is a non-shearing angle area, namely an area where the shearing edge does not contact the strip steel, in the area, the shearing edge is completely separated from the strip steel, shearing with different lengths is realized by adjusting the speed of flying shears in the area, and the range of the non-shearing angle area is alpha to (360-alpha) because the shearing angle is alpha; the third zone is a front shearing angle zone, namely a zone between the cutting edge of the flying shears and the shearing point of the flying shears when the flying shears and the strip steel start to contact, and the flying shears must be accelerated to the strip steel speed V before entering the zone, so that normal shearing can be guaranteed.
Preferably, the method further comprises: and calculating the speed set values and the acceleration set values of the flying shear blades in the front shear angle area and the rear shear angle area according to the actual angle values of the shear blades and the actual speed values of the strip steel.
The method comprises the following steps of calculating speed set values and acceleration set values of the flying shear blades in a front shear angle area and a rear shear angle area according to the actual angle value of the shear blades and the actual speed value of strip steel:
because the strip steel runs in the horizontal direction and the flying shear blades rotate along the circular arc, the speeds of the strip steel and the flying shear blades are kept consistent in a shear angle, and the speeds of the strip steel and the flying shear blades are kept consistent in the horizontal direction strictly speaking. Then the set speed of the flying shear in the shearing area is calculated as:
v1=v3=V/(cosθ);
in the formula: v. of1Setting the flying shear speed in the rear shear angle; v. of3Setting the flying shear speed in the front shear angle; v is the actual linear speed of the strip steel; theta is a flying shear angle and satisfies 0<θ<Alpha or 360-alpha<θ<360(α is the shear angle).
The acceleration set value of the flying shear in the shearing area is as follows:
in the formula: a is1Setting the flying shear acceleration in the rear shear angle; a is3Setting the flying shear acceleration in the front shear angle; v is the actual linear speed of the strip steel; theta is a flying shear angle and satisfies 0<θ<Alpha or 360-alpha<θ<360(α is the shear angle); and R is the rotating radius of the cutting edge.
As can be seen from fig. 4, 5 and 6, in the fixed-length shearing process, if the acceleration and deceleration of the flying shears is determined, when the flying shears rotate to any position point in the non-shearing area, the distance value from the next shearing point of the strip steel to the flying shears, the time spent in the fixed-length shearing, the angle value of the flying shears and the speed value of the flying shears are in one-to-one correspondence, so that the angle setting value and the speed setting value of the flying shears can be calculated by calculating the distance value of the next shearing point through the measuring roller encoder as long as the acceleration and deceleration of the flying shears in the non-shearing area are determined.
From the perspective of protecting mechanical equipment, under the condition of meeting the control requirement, the excessively severe acceleration and deceleration process caused by the excessively large acceleration and deceleration of the flying shears is avoided as much as possible, when the fixed-length shearing needs to adjust the speed of the flying shears, the optimal control strategy is to keep the absolute values of the acceleration and the deceleration consistent, and ensure the smooth acceleration and deceleration curve of the flying shears as much as possible, as shown in fig. 5 and 6.
Through the analysis, in the fixed-length shearing process, when the running distance of the strip steel keeping speed V is the shearing set length L, the running length of the flying shear is 2 pi R, and the thickness of the produced strip steel and the superposition amount of the shear blades are much smaller than the running radius of the shear blades, so the calculated shearing angle is smaller (below 15 degrees), and the speed of the flying shear in the shearing angle is approximately equal to V;
accordingly, the acceleration of the flying shear blade in the non-shearing angle is calculated according to the shearing length set value, the actual linear speed of the strip steel, the rotating radius of the shear blade and the shearing angle, and specifically comprises the following steps:
when the shearing set length L is less than or equal to 2 pi R x (2-alpha/180), the flying shears decelerate first and then accelerate or accelerate first and then decelerate, the middle does not need to stop, the acceleration and deceleration switching point is at the T/2 time of single fixed-length shearing, the acceleration is switched from A to-A, and the calculation formula is as follows:
t1=t2=T/2;
when the shearing set length L is more than 2 pi R x (2-alpha/180), the flying shear is decelerated to stop firstly, and then accelerated after a period of time. Its acceleration is at t1Is switched from A to 0 at t2Is switched from 0 to-A, t1、t2The calculation formula for A is as follows:
in the formula, L is a set value of the shearing length; v is the actual linear speed of the strip steel; r is the rotating radius of the shear blade; alpha is a shear angle; t (L/V) is used for single fixed-length cutting; a is the acceleration of the flying shear; t is t1A first speed switching time point in a non-shearing angle area; t is t2The second speed switching time point is the non-shear angle region.
Wherein, the distance value from the next shearing point to the flying shear is calculated by the measuring roller as follows:
the measuring roller is arranged at the front part of the flying shear, when the cutting edge of the flying shear passes through a shearing point, the counting value of the measuring roller encoder is reset, then in the next fixed-length shearing process, the distance value from the next shearing point to the flying shear can be calculated by utilizing the accumulated value of the measuring roller encoding pulses, and the calculation formula is as follows:
in the formula, l' is the distance value from the next shearing point to the flying shear; l is a set value of the shearing length; i is1Encoding the pulse integration value for the measuring roll; d1 is the measurement roll diameter; i.e. i1For measuring the gear box transformation ratio of the roller; n is1The number of pulses per revolution is measured for the roller encoder.
The speed set value of the flying shear blade in the non-shearing angle area is calculated according to the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the flying shear blade in the non-shearing angle area, and specifically comprises the following steps:
the used time t ' ═ L ')/V of the fixed-length shearing can be calculated according to the distance value L ' from the next shearing point of the strip steel to the flying shears, wherein L is the set value of the shearing length; v is the actual speed of the strip steel. From the foregoing analysis, the flying shear speed set point calculation formula can be obtained by combining fig. 5 and 6 as follows:
in the formula, v2Setting the flying shear speed in a non-shearing angle; a is the acceleration of the flying shear; l' is the distance value from the next shearing point to the flying shear; r is the rotating radius of the shear blade; alpha is a shear angle; v is the actual linear speed of the strip steel; l is the setting of the shearing length; t' is the time used for the fixed-length cutting;the time taken for the flying shear to rotate through the shear angle; t is t1A first speed switching time point in a non-shearing angle area; t is t2A second speed switching time point for the non-shear angle region; t (═ L/V) is used for single fixed length cutting.
To ensure the control precision of fixed-length shearing, the position of the cutting edge of the flying shear must be controlled in real time through the position of the shearing point on the strip steel. The algorithm determines the acceleration of the flying shear, calculates the speed setting of the flying shear according to the distance value from the next shearing point to the flying shear, and controls the position of the cutting edge of the flying shear by using the speed of the flying shear. The method is used for open-loop control of the position of the cutting edge, and the control precision is difficult to guarantee.
The method comprises the following steps of calculating the angle setting of a flying shear blade in a non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear:
from the foregoing analysis, the flying shear angle setting value calculation formula can be obtained by combining fig. 5 and fig. 6 as follows:
in the formula, theta is a set value of the flying shear angle and satisfies alpha<θ<360-alpha; l is the setting of the shearing length; l' isThe distance value from the next shearing point to the flying shear; a is the acceleration of the flying shear; r is the rotating radius of the shear blade; alpha is a shear angle; v is the actual linear speed of the strip steel; t' is the time spent in the fixed-length shearing;the time taken for the flying shear to rotate through the shear angle; t is t1A first speed switching time point in a non-shearing angle area; t is t2A second speed switching time point for the non-shear angle region; t (═ L/V) is used for single fixed length cutting.
Wherein, according to flying shear cutting edge angle setting value and actual angle carry out closed loop control specifically to flying shear cutting edge position and do: and calculating the angle set value of the cutting edge of the flying shear according to the distance value from the shearing point on the strip steel to the flying shear. The difference between the actual angle of the flying shear and the actual angle of the flying shear is used as an adjustment quantity to carry out closed-loop control on the position of the cutting edge of the flying shear in the non-shearing angle. In order to prevent speed oscillations that may be caused by the control of the position of the cutting edge, a proportional controller may be selected as the position regulator, and the regulator output is superimposed as an additional speed in the previously calculated flying shear speed setting as the final flying shear speed setting output, as shown in fig. 7.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (6)
1. A control method for realizing high-precision fixed-length shearing of a rotary flying shear comprises the following steps:
calculating the shearing angle of the flying shear, and determining the non-shearing angle of the flying shear according to the shearing angle of the flying shear;
calculating the acceleration of the flying shear blade in the non-shearing angle according to the shearing length set value, the actual linear speed of the strip steel, the rotating radius of the shear blade and the shearing angle;
calculating the distance value from the next shearing point to the flying shear through the measuring roller;
calculating the speed set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the cutting edge of the flying shear in the non-shearing angle area;
calculating the angle set value of the cutting edge of the flying shear in the non-shearing angle area according to the distance value from the next shearing point of the strip steel to the flying shear and the speed set value of the cutting edge of the flying shear in the non-shearing angle area;
performing closed-loop control on the position of the cutting edge of the flying shear according to the set value and the actual angle of the cutting edge of the flying shear;
wherein the method further comprises: dividing a rotating circle of a cutting edge of the flying shear into three areas, namely a rear cutting angle area, a non-cutting angle area and a front cutting angle area by taking a cutting angle as a boundary, wherein the rear cutting angle area is an area between a cutting edge and a strip steel separation area from a cutting point of the flying shear to the preparation of the cutting edge after the cutting is finished; a non-shearing angle area, namely an area where the shearing edge does not contact the strip steel, wherein the shearing edge and the strip steel are completely separated in the area; the front shearing angle area is an area between the flying shear blade and the shearing point of the flying shear, which is the area where the flying shear blade and the strip steel start to contact with each other;
the method comprises the following steps of calculating a speed set value and an acceleration set value of a flying shear blade in a front shear angle area and a rear shear angle area according to an actual angle value of the shear blade and an actual speed value of strip steel, and specifically comprises the following steps:
because the strip steel runs in the horizontal direction, the flying shear blades rotate along the circular arc, the speeds of the strip steel and the flying shear blades are kept consistent in the shearing angle, and then the set speed of the flying shear in the shearing area is calculated as follows:
v1=v3=V(cosθ);
in the formula: v. of1Setting the flying shear speed in the rear shear angle; v. of3Setting the flying shear speed in the front shear angle; v is the actual linear speed of the strip steel; theta is a flying shear angle and satisfies the condition that theta is more than 0 and less than alpha or 360-alpha and less than 360, and alpha is a shear angle;
the acceleration set value of the flying shear in the shearing area is as follows:
in the formula: a is1For acceleration of internal flying shear at rear shear angleDetermining; a is3Setting the flying shear acceleration in the front shear angle; v is the actual linear speed of the strip steel; theta is a flying shear angle and satisfies the condition that theta is more than 0 and less than alpha or 360-alpha and less than theta and less than 360 (alpha is a shear angle); r is the rotating radius of the shear blade;
the method comprises the following steps of calculating the acceleration of the flying shear blade in a non-shearing angle according to a shearing length set value, the actual linear speed of strip steel, the rotating radius of the shear blade and the shearing angle:
in the fixed-length shearing process, when the strip steel keeps the running distance of the speed V as the shearing set length L, the running length of the flying shear is 2 pi R;
when the shearing set length L is less than or equal to 2 pi R x (2-alpha/180), the flying shears decelerate first and then accelerate or accelerate first and then decelerate, the middle does not need to stop, the acceleration and deceleration switching point is at the T/2 time of single fixed-length shearing, the acceleration is switched from A to-A, and the calculation formula is as follows:
t1=t2=T/2;
when the shearing set length L is more than 2 pi R x (2-alpha/180), the flying shear is decelerated to stop firstly, and then accelerated after a period of time, and the acceleration is t1Is switched from A to 0 at t2Is switched from 0 to-A, t1、t2The calculation formula for A is as follows:
in the above formula, L is the set value of the shearing length(ii) a V is the actual linear speed of the strip steel; r is the rotating radius of the shear blade; alpha is a shear angle; t (L/V) is used for single fixed-length cutting; a is the acceleration of the flying shear; t is t1Switching time points for the first acceleration in a non-shearing angle area; t is t2The second acceleration switching time point is in the non-shear angle region.
2. The control method for realizing the high-precision fixed-length shearing of the rotary flying shear as claimed in claim 1, wherein the method is characterized in that the shearing angle of the flying shear is calculated, and the determining of the non-shearing angle area of the flying shear according to the shearing angle of the flying shear is specifically as follows:
because the cutting edge contacts the strip steel only in a certain angle range around the shearing point of the flying shear, namely, the left side and the right side of the shearing point of the flying shear are respectively provided with a contact angle which is a shearing angle, the size of the shearing angle is related to the coincidence quantity between the upper cutting edge and the lower cutting edge of the flying shear, the thickness of the strip steel and the rotating radius of the cutting edge of the flying shear, and the calculation formula is as follows:
in the formula: alpha is a shear angle; r is the rotating radius of the shear blade; MD is the thickness of the strip steel; MU is the overlapping amount between the upper and lower shear blades;
and in the non-shearing angle area, namely the area where the shearing edge does not contact the strip steel, after the shearing angle alpha is calculated, the range of the non-shearing angle area is alpha to (360-alpha).
3. The control method for realizing the high-precision fixed-length shearing of the rotary flying shear according to claim 1, wherein the calculation of the distance value from the next shearing point to the flying shear through the measuring roll is specifically as follows:
the measuring roll is arranged at the strip steel in front of the flying shear, when the cutting edge of the flying shear passes through the cutting point of the flying shear, the counting value of the encoder of the measuring roll is reset, the accumulated value of the coded pulses of the measuring roll is used for calculating the distance value from the next cutting point to the flying shear, and the calculation formula is as follows:
in the formula, l' is the distance value from the next shearing point to the flying shear; l is a set value of the shearing length; i is1Encoding the pulse integration value for the measuring roll; d1To measure roll diameter; i.e. i1For measuring the gear box transformation ratio of the roller; n is1The number of pulses per revolution is measured for the roller encoder.
4. The control method for realizing the high-precision fixed-length shearing of the rotary flying shears according to claim 1, wherein the calculation of the speed set value of the flying shear blade in the non-shearing angle region according to the distance value from the next shearing point of the strip steel to the flying shears and the acceleration of the flying shear blade in the non-shearing angle is specifically as follows:
the used time t ' ═ L ')/V of the fixed-length shearing can be calculated according to the distance value L ' from the next shearing point of the strip steel to the flying shears, wherein L is the set value of the shearing length; v is the actual speed of the strip steel, and the calculation formula of the speed set value of the flying shear obtained by combining the distance value from the next shearing point of the strip steel to the flying shear and the acceleration of the cutting edge of the flying shear in the non-shearing angle is as follows:
in the formula, v2Setting the flying shear speed in a non-shearing angle; a is the acceleration of the flying shear; l' is the distance value from the next shearing point to the flying shear; r is the rotating radius of the shear blade; alpha is a shear angle; v is the actual linear speed of the strip steel; l is the setting of the shearing length; t' is the time used for the fixed-length cutting;the time taken for the flying shear to rotate through the shear angle; t is t1A first speed switching time point in a non-shearing angle area; t is t2A second speed switching time point for the non-shear angle region; t (═ L/V) is used for single fixed length cutting.
5. The control method for realizing the high-precision fixed-length shearing of the rotary flying shears as claimed in claim 1, wherein the calculation of the angle setting of the cutting edge of the flying shears in the non-shearing angle region according to the distance value from the next shearing point of the strip steel to the flying shears is specifically as follows:
the calculation formula of the angle set value of the shearing blade in the non-shearing angle area is obtained by combining the distance value from the next shearing point of the strip steel to the flying shears and the speed set value of the shearing blade of the flying shears in the non-shearing angle area, and is as follows:
in the formula, theta is a set value of the flying shear angle and satisfies that alpha is more than theta and less than 360-alpha; l is the setting of the shearing length; l' is the distance value from the next shearing point to the flying shear; a is the acceleration of the flying shear; r is the rotating radius of the shear blade; alpha is a shear angle; v is the actual linear speed of the strip steel; t' is the time spent in the fixed-length shearing; t' is the time taken for the flying shear to rotate through the shear angle; t is t1A first speed switching time point in a non-shearing angle area; t is t2A second speed switching time point for the non-shear angle region; t (═ L/V) is used for single fixed length cutting.
6. The control method for realizing the high-precision fixed-length shearing of the rotary flying shears according to claim 1 is characterized in that the closed-loop control of the positions of the cutting edges of the flying shears according to the set values and the actual angles of the cutting edges of the flying shears is specifically as follows: and calculating the angle set value of the cutting edge of the flying shear according to the distance value from the shearing point on the strip steel to the flying shear.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910939774.3A CN110673546B (en) | 2019-09-30 | 2019-09-30 | Control method for realizing high-precision fixed-length shearing of rotary flying shear |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910939774.3A CN110673546B (en) | 2019-09-30 | 2019-09-30 | Control method for realizing high-precision fixed-length shearing of rotary flying shear |
Publications (2)
Publication Number | Publication Date |
---|---|
CN110673546A CN110673546A (en) | 2020-01-10 |
CN110673546B true CN110673546B (en) | 2021-02-09 |
Family
ID=69080430
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201910939774.3A Active CN110673546B (en) | 2019-09-30 | 2019-09-30 | Control method for realizing high-precision fixed-length shearing of rotary flying shear |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110673546B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112068491B (en) * | 2020-09-02 | 2021-09-21 | 四川省达州钢铁集团有限责任公司 | Method for improving response speed of flying shear |
CN114932265B (en) * | 2022-06-15 | 2023-06-23 | 中冶南方工程技术有限公司 | Flying shear control method and system |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105965088A (en) * | 2016-06-01 | 2016-09-28 | 中国重型机械研究院股份公司 | Calculation method for drive control parameters of drum type flying shear based on specified lengths of shearing targets |
CN107150146A (en) * | 2016-03-04 | 2017-09-12 | 北新集团建材股份有限公司 | Flying shear control system |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101776888B (en) * | 2009-07-10 | 2012-05-09 | 固高科技(深圳)有限公司 | Shearing method of flying shears and special motion controller for flying shears |
US8910570B2 (en) * | 2009-11-13 | 2014-12-16 | Preco, Inc. | Apparatus and method for calculating registration error of a rotary die |
CN102773256B (en) * | 2011-05-11 | 2015-04-08 | 上海宝信软件股份有限公司 | Optimal control method for strip tail shear by flying shear at continuous annealing unit inlet |
US10232453B2 (en) * | 2016-05-26 | 2019-03-19 | Wirtz Manufacturing Company, Inc. | Battery plate cutter system and method |
-
2019
- 2019-09-30 CN CN201910939774.3A patent/CN110673546B/en active Active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107150146A (en) * | 2016-03-04 | 2017-09-12 | 北新集团建材股份有限公司 | Flying shear control system |
CN105965088A (en) * | 2016-06-01 | 2016-09-28 | 中国重型机械研究院股份公司 | Calculation method for drive control parameters of drum type flying shear based on specified lengths of shearing targets |
Non-Patent Citations (2)
Title |
---|
起停式飞剪控制***;张旭东;《电气传动》;20061130;第36卷(第11期);第43-46页 * |
飞剪式纸护角定长剪切机***的研制;刘劲阳;《包装工程》;20170831;第35卷(第15期);第25-28、34页 * |
Also Published As
Publication number | Publication date |
---|---|
CN110673546A (en) | 2020-01-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN110673546B (en) | Control method for realizing high-precision fixed-length shearing of rotary flying shear | |
CN102632083B (en) | Method for compensating working roll diameter of end stander rolling mill of flying shear control system of bar production line | |
CN105965088B (en) | Drum type flying shear based on shearing target cut lengths is driven control parameter computational methods | |
JPH08267163A (en) | Device for straightening, measuring and cutting wire | |
CN104942002B (en) | Hot rolled strip intermediate billet head cutting control method | |
CN103962625A (en) | Continuous polar plate slitter machine and use method thereof | |
CN103056171A (en) | Quadratic curve control method for short stroke of rough rolling vertical roll | |
CN102773256B (en) | Optimal control method for strip tail shear by flying shear at continuous annealing unit inlet | |
JPS6227271A (en) | Speed control device for continuous processing facility | |
CN104723172B (en) | A kind of steel plate shear gauge and its method for scaling | |
CN102873105B (en) | Prediction method for rectangular flat material angular rolling width | |
CN204546650U (en) | A kind of online film cutter | |
CN104971950A (en) | Automatic deceleration control method for cold continuous rolling mill | |
Khramshin | Ways to compensate for static deviations in speed in electric drives of broad-strip hot rolling-mill stands | |
US5381342A (en) | System for trimming a continuously moving metal strip | |
CN103294003A (en) | Control system and control method of non-blocking rotary cutter with adjustable rotary cutting linear speed | |
CN106055796A (en) | Drum flying shear transmission design parameter calculation method based on minimum target cut lengths | |
CN110153182A (en) | Coil Box and shearing strip steel head method for hot continuous rolling shearing strip steel head | |
CN112191693B (en) | Method for cutting waste at tail of uncoiler of cold-rolled sheet treatment line | |
CN111545577B (en) | Tension control method for five-stand cold continuous rolling mill in dynamic specification changing stage | |
CN204867618U (en) | Device and fossil fragments cold rolling mill are cut to fossil fragments | |
CN114932265B (en) | Flying shear control method and system | |
CN107755793A (en) | A kind of shut-off mechanism | |
Song | Research of High-Precision Control Method for Rotary Flying Shear | |
CN102527750A (en) | Tracking method of traversing speed and position of water tank wire-drawing machine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |