CN1887463A - Feed forward control method for wall thickness of tension reducing machine - Google Patents

Abstract

The feed forward control method for wall thickness of tension reducing machine includes the following steps: 1. reading out the ideal correlated technological parameter data of the steel pipe to be rolled and on-line measuring its practical correlated technological parameter data; 2. real-time on-line calculating the wall thickness of continuously rolled pipe and calculating the error; 3. regulating the roller rotation speed based on the expression I for reaching ideal thickness in the case of the error within the required range; and 4. calculating the roller rotation speed correcting amount based on expression II before returning to the step 3 in the case of the error beyond the required range. The present invention utilizes the on-line data of hot rolling process in regulating the rolling rotation speed distribution of rollers adaptively to raise the rolled pipe product wall thickness precision.

Description

Feed forward control method for wall thickness of tension reducing machine

Technical field

The present invention relates to a kind of seamless steel pipe feed forward control method for wall thickness of tension reducing machine, relate in particular to a kind of seamless steel pipe stretch reducing process wall thickness feed forward self-adaptation control method based on supplied materials hollow forging wall thickness deviation.

Background technology

What the bar of seamless steel pipe hot-rolling process adopted mostly at present is the flame cutting, and pipe supplied materials deviation is bigger.If what tandem mill adopted is that full-floating plug is rolling, then its process conditions have determined to subtract supplied materials, and just the wall thickness deviation of mandrel mill-made shell is big, and the wall thickness variation that is mainly reflected in adjacent steel pipe is bigger.At present, subtract the machine operation opening, be to be surveyed long according to on-the-spot tandem rolling and opened the long and thickness measuring data of the survey that subtracts production tube by production operators, and an artificial rotating speed that subtracts the machine roll of adjusting is corrected this wall thickness deviation.Under the allegro condition of production, this adjustment mode poor effect is adjusted untimely even can be played the effect of deterioration.

Summary of the invention

The object of the present invention is to provide a kind of feed forward control method for wall thickness of tension reducing machine, utilize the online data of seamless steel pipe hot-rolling process material flow tracing to come self adaptation to adjust the rolling rotating speed distribution of each breast roller of stretch-reducing mill, thereby opening of avoiding that origin material hollow forging wall thickness deviation caused subtracts the fished pipe wall thickness deviation, guarantees the wall thickness S of fished pipe _N ^kWith desirable wall thickness S _N ^dBasically identical.

For achieving the above object, the invention provides a kind of feed forward control method for wall thickness of tension reducing machine, it comprises following steps:

Step 1. reads the desirable related process supplemental characteristic of steel pipe to be rolled, the online actual related process supplemental characteristic that records steel pipe to be rolled;

Step 11. subtracts the desirable related process supplemental characteristic of reading steel pipe to be rolled in the pass schedule, desirable pipe weight B by opening _d, desirable tandem rolling length of tube L _d, desirable tandem rolling external diameter of pipe D ₀ ^d, desirable tandem rolling thickness of pipe wall S ₀ ^d, desirable production tube outer diameter D _N ^d, desirable production tube wall thickness S _N ^d, desirable opening subtract machine inlet frame working diameter φ ₀ ^d, desirable opening subtract machine outlet frame working diameter φ _N ^d, desirable opening subtract machine inlet gantry speed v ₀ ^d, desirable opening subtract machine outlet gantry speed v _N ^d

Online actual pipe weight B, tandem rolling length of tube L, the tandem rolling external diameter of pipe D of recording of step 12. ₀ ^k, the production tube outer diameter D _N ^k, production tube wall thickness S _N ^k, open and to subtract machine inlet frame working diameter φ ₀ ^k, open and to subtract machine outlet frame working diameter φ _N ^k, open and to subtract machine inlet gantry speed v ₀ ^k, open and to subtract machine outlet gantry speed v _N ^kAnd the tandem rolling external diameter of pipe that reality is set is D ₀ ^dWith desirable tandem rolling external diameter of pipe D ₀ ^kUnanimity, promptly $D_0^d=D_0^k;$

Step 2. real-time online calculates tandem rolling thickness of pipe wall S ₀ ^k, and calculate its error;

Step 21. because $\frac{B_d}{B}=\frac{(D_0^d-S_0^d)S_0^d{L}_d}{(D_0^k-S_0^k)S_0^{k}L},$ And $D_0^d=D_0^k,$ Then have $\frac{B_d}{B}=\frac{(D_0^d-S_0^d)S_0^d{L}_d}{(D_0^d-S_0^k)S_0^{k}L},$ Promptly ${\left(S_0^k\right)}^2-D_0^d{S}_0^k+\frac{(D_0^d-S_0^d)S_0^d{L}_{d}B}{{\mathrm{LB}}_d}=0,$ Order $C=\frac{(D_0^d-S_0^d)S_0^d{L}_{d}B}{{\mathrm{LB}}_d},$ Then can calculate actual tandem rolling thickness of pipe wall S ₀ ^kFor: $S_0^k=\frac{D_d-\sqrt{D_d^2-4\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="A20051002743100122.png,A20051002743100131.png"\; state="\{\{state\}\}">C</figure-callout>}}}{2};$

Step 22: according to desirable tandem rolling thickness of pipe wall S _d, calculate the error of actual tandem rolling thickness of pipe wall S, if error does not meet the demands, then go to step 4 earlier, carry out step 3 again; If error meets the demands, then continue only carry out step 3;

Step 3. subtracts the online adjustment of roll rotational speed of machine feedforward Self Adaptive Control, makes to open a wall thickness that subtracts production tube and reach desirable wall thickness;

Step 31.,, has for desired quantity and the actual numerical value that records under the stable rolling state by the constancy of volume rule according to the standard pass schedule:

$(D_0^d-S_0^d)S_0^d{\mathrm{\&phi;}}_0^d{v}_0^d=(D_N^d-S_N^d)S_N^d{\mathrm{\&phi;}}_N^d{v}_N^d,$

$(D_0^k-S_0^k)S_0^k{\mathrm{\&phi;}}_0^k{v}_0^k=(D_N^k-S_N^k)S_N^k{\mathrm{\&phi;}}_N^k{v}_N^k;$

In the operation of rolling, when roll rotational speed changed, the working diameter of roll also can change; Because the adjustment of roll rotational speed scope generally can not surpass 10% of former rotating speed, and the adjustment trend of each frame rotating speed is consistent; So in self adaptation rotating speed adjustment control, the variation of roll working diameter is little, can get thus: ${\mathrm{\&phi;}}_0^k\&ap;{\mathrm{\&phi;}}_0^d,{\mathrm{\&phi;}}_N^k\&ap;{\mathrm{\&phi;}}_N^d;$

In addition, because the external diameter of steel pipe can be got thus by the pass decision of rolling mill roll: $D_0^k\&ap;D_0^d,$

$D_N^k\&ap;D_N^d;$

Can get thus: $(D_0^d-S_0^d)S_0^d{\mathrm{\&phi;}}_0^d{v}_0^d=(D_N^d-S_N^d)S_N^d{\mathrm{\&phi;}}_N^d{v}_N^d,(D_0^d-S_0^k)S_0^k{\mathrm{\&phi;}}_0^k{v}_0^k=(D_N^k-S_N^k)S_N^k{\mathrm{\&phi;}}_N^k{v}_N^k;$ So $\frac{(D_0^d-S_0^d)S_0^d{\mathrm{\&phi;}}_0^d{v}_0^d}{(D_0^d-S_0^k)S_0^k{\mathrm{\&phi;}}_0^d{v}_0^k}=\frac{(D_N^d-S_N^d)S_N^d{\mathrm{\&phi;}}_N^d{v}_N^d}{(D_N^d-S_N^k)S_N^k{\mathrm{\&phi;}}_N^d{v}_N^k},$ Promptly $\frac{(D_0^d-S_0^d)S_0^d{v}_0^d}{(D_0^d-S_0^k)S_0^k{v}_0^k}=\frac{(D_N^d-S_N^d)S_N^d{v}_N^d}{(D_N^d-S_N^k)S_N^k{v}_N^k};$

Step 32. guarantees the wall thickness S of fished pipe because the control of feedforward wall thickness is after changing appears in the wall thickness of mandrel mill-made shell _N ^kWith desirable wall thickness S _N ^dUnanimity, promptly $S_N^k=S_N^d;$ For guaranteeing rhythm of production, keep the rotating speed of outlet running roller constant substantially, promptly simultaneously $v_N^d=v_N^k,$ So the method that roll rotational speed is adjusted in the Self Adaptive Control of feedforward wall thickness is: $v_0^k=\frac{(D_0^d-S_0^d)S_0^d}{(D_0^d-S_0^k)S_0^k}{v}_0^d,$ Realize control automatically in real time;

The correction of step 4, calculating roll rotational speed:

Will $v_0^k=\frac{(D_0^d-S_0^d)S_0^d}{(D_0^d-S_0^k)S_0^k}{v}_0^d$ Further write as increment type, had: $v_0^k=v_0^k+\frac{(D_0^d-S_0^d-S_0^k)}{(D_0^d-S_0^k)S_0^k}{v}_0^d{\mathrm{\&Delta;<figure-callout\; id="0"\; label="S"\; filenames="A20051002743100121.png,A20051002743100122.png"\; state="\{\{state\}\}">S</figure-callout>}}_0,$ Wherein ${\mathrm{\&Delta;<figure-callout\; id="0"\; label="S"\; filenames="A20051002743100121.png,A20051002743100122.png"\; state="\{\{state\}\}">S</figure-callout>}}_0=S_0^d-S_0^k;$ Because the finishing frame mainly participates in the shaping of steel pipe, when carrying out wall thickness feed forward control, we keep their roll rotational speed constant, and only allow tension force rise frame and work housing participation speed governing.If allow k-1 frame participate in speed governing, promptly the rotating speed of k frame is fixed, then following distribution respectively participates in the speed of the frame of speed governing: $v_i^k=v_i^d+\frac{(v_k^d-v_i^d)(D_0^d-S_0^d-S_0^k)}{(v_k^d-v_0^d)(D_0^d-S_0^k)S_0^k}{v}_0^d{\mathrm{\&Delta;<figure-callout\; id="0"\; label="S"\; filenames="A20051002743100121.png,A20051002743100122.png"\; state="\{\{state\}\}">S</figure-callout>}}_0,$ Obtain the correction of roll rotational speed, revise pass schedule.

Feed forward control method for wall thickness of tension reducing machine provided by the invention, utilize the pipe of the corresponding supplied materials hollow forging that accurate material flow tracing obtains to weigh, the survey long data behind the tandem mill, calculate the wall thickness data of supplied materials hollow forging, then according to the relation of the stretch reducing mill wall thickness regularity of distribution and steel pipe initial wall thickness, distribute at fall into a trap the get it right rolling rotating speed of each breast roller of answering of the operation of rolling, realize opening the feedforward Self Adaptive Control that subtracts the machine average wall thickness, reduce opening that origin material hollow forging wall thickness deviation caused as far as possible and subtract the fished pipe wall thickness deviation, guarantee the wall thickness S of fished pipe _N ^kWith desirable wall thickness S _N ^dBasically identical.

Description of drawings

Fig. 1 is the distribution situation of 120 test hollow forgings and fished pipe wall thickness mean value in the embodiment of the invention;

Fig. 2 is the distribution of the average wall thickness of 120 test hollow forgings in the embodiment of the invention;

Fig. 3 is the distribution of the average wall thickness behind 120 test hollow forging finished products in the embodiment of the invention.

The specific embodiment

Below, specific embodiments of the invention are described better by Fig. 1～Fig. 3.

The stretch reducing process of at first choosing the BRDBY steel pipe of ideal format carries out wall thickness feed forward Self Adaptive Control pilot production, the parameter of this steel pipe is as follows: waste external diameter of pipe 152.50mm, waste thickness of pipe wall 6.00mm, production tube external diameter 73.03mm, production tube wall thickness 5.51mm, participate in 18 of rolling machine frames, 12 of rotating speed fixed frames;

Because tension force decline frame is the finishing frame, the main effect in rolling is the circularity of regulating steel pipe, therefore, thickens control for average wall thickness control and pipe end, only allows tension force rise frame and work housing participation steady-state speed adjustment and dynamically rotating speed adjustment.

According to feed forward control method for wall thickness of tension reducing machine provided by the invention, 120 BRDBY steel pipes choosing are tested production, obtain actual wall thickness of hollow forging and production tube average wall thickness situation as all 120 listed test steel pipes of table 1.

The steel pipe radical	The actual wall thickness of hollow forging (mm)	Production tube average wall thickness (mm)
			1	6.142	5.510
2	5.993	5.497
			3	6.205	5.540
4	6.012	5.542
			5	6.189	5.521
6	6.117	5.532
			7	5.817	5.500
8	6.210	5.528
			9	5.884	5.520
10	6.009	5.525
			11	6.198	5.501
12	5.945	5.530
			13	6.012	5.501
14	5.878	5.483
			15	6.006	5.504
16	6.007	5.530
			17	6.007	5.478

18	6.027	5.486
			19	5.959	5.513
20	5.816	5.501
			21	5.811	5.470
22	5.970	5.504
			23	5.931	5.471
24	5.909	5.474
			25	5.826	5.518
26	5.964	5.494
			27	5.925	5.522
28	6.011	5.533
			29	6.084	5.535
30	5.946	5.490
			31	6.057	5.510
32	5.877	5.510
			33	5.914	5.488
34	5.864	5.504
			35	5.882	5.504
36	5.834	5.512
			37	5.845	5.525
38	6.007	5.499
			39	6.200	5.479
40	5.992	5.480
			41	5.905	5.525
42	5.919	5.538
			43	5.900	5.557
44	5.934	5.519
			45	6.024	5.518
46	6.019	5.530
			47	6.051	5.515

48	5.950	5.490
			49	5.991	5.551
50	5.935	5.532
			51	5.935	5.535
52	6.001	5.559
			53	6.095	5.552
54	6.043	5.560
			55	6.085	5.504
56	6.058	5.509
			57	5.943	5.523
58	6.029	5.513
			59	5.996	5.485
60	6.117	5.486
			61	6.149	5.516
62	6.093	5.541
			63	6.093	5.509
64	6.009	5.523
			65	5.995	5.498
66	6.031	5.546
			67	6.051	5.538
68	6.003	5.529
			69	5.980	5.523
70	6.029	5.506
			71	6.032	5.484
72	6.131	5.516
			73	5.972	5.476
74	6.025	5.515
			75	6.033	5.516
76	6.068	5.513
			77	6.081	5.494

78	6.008	5.527
			79	6.034	5.525
80	5.964	5.490
			81	6.047	5.515
82	6.152	5.498
			83	6.045	5.510
84	6.073	5.509
			85	6.145	5.493
86	5.975	5.495
			87	5.950	5.521
88	5.999	5.522
			89	6.005	5.488
90	6.131	5.497
			91	6.166	5.505
92	6.007	5.491
			93	6.022	5.493
94	6.121	5.533
			95	6.061	5.485
96	5.948	5.538
			97	5.976	5.489
98	5.942	5.533
			99	5.952	5.518
100	6.146	5.509
			101	6.136	5.500
102	5.967	5.541
			103	6.004	5.539
104	5.955	5.490
			105	6.061	5.552
106	5.948	5.534
			107	5.976	5.516

108	5.942	5.541
			109	5.952	5.509
110	6.146	5.523
			111	6.136	5.498
112	5.967	5.546
			113	6.004	5.538
114	5.955	5.529
			115	5.973	5.523
116	6.061	5.506
			117	5.948	5.484
118	5.976	5.516
			119	5.942	5.536
120	5.952	5.515

The actual wall thickness of hollow forging and the production tube average wall thickness of the continuous 120 test steel pipes of table 1

Fig. 1 is the diagrammatic representation of the listed data of table 1, can see that the wall thickness range of supplied materials hollow forging is between 5.8 millimeters to 6.3 millimeters, and after wall thickness control, the scope of production tube average wall thickness greatly reduces the wall thickness deviation of fished pipe between 5.47 millimeters to 5.56 millimeters.

Fig. 2 and 3 provided the distribution of the average wall thickness of 120 hollow forgings and production tube respectively, therefrom can further see, FEEDFORWARD CONTROL remedied supplied materials hollow forging wall thickness deviation band preferably influence, reduced the wall thickness deviation of production tube.

Feed forward control method for wall thickness of tension reducing machine provided by the invention, utilize the pipe of the corresponding supplied materials hollow forging that accurate material flow tracing obtains to weigh, the survey long data behind the tandem mill, calculate the wall thickness data of supplied materials hollow forging, then according to the relation of the stretch reducing mill wall thickness regularity of distribution and steel pipe initial wall thickness, distribute at fall into a trap the get it right rolling rotating speed of each breast roller of answering of the operation of rolling, realize opening the feedforward Self Adaptive Control that subtracts the machine average wall thickness, reduce opening that origin material hollow forging wall thickness deviation caused as far as possible and subtract the fished pipe wall thickness deviation, guarantee the wall thickness S of fished pipe _N ^kWith desirable wall thickness S _N ^dBasically identical can be improved technical level to a great extent, produces huge economic benefit.

Claims (3)

1. feed forward control method for wall thickness of tension reducing machine is characterised in that it comprises following steps:

Step 1. reads the desirable related process supplemental characteristic of steel pipe to be rolled, the online actual related process supplemental characteristic that records steel pipe to be rolled;

Step 11. subtracts the desirable related process supplemental characteristic of reading steel pipe to be rolled in the pass schedule, desirable pipe weight B by opening _d, desirable tandem rolling length of tube L _d, desirable tandem rolling external diameter of pipe D _O ^d, desirable tandem rolling thickness of pipe wall S _O ^d, desirable production tube outer diameter D _N ^d, desirable production tube wall thickness S _N ^d, desirable opening subtract machine inlet frame working diameter φ _O ^d, desirable opening subtract machine outlet frame working diameter φ _N ^d, desirable opening subtract machine inlet gantry speed v _O ^d, desirable opening subtract machine outlet gantry speed v _N ^d

Online actual pipe weight B, tandem rolling length of tube L, the tandem rolling external diameter of pipe D of recording of step 12. _O ^k, the production tube outer diameter D _N ^k, production tube wall thickness S _N ^k, open and to subtract machine inlet frame working diameter φ _O ^k, open and to subtract machine outlet frame working diameter φ _N ^k, open and to subtract machine inlet gantry speed v _O ^kOpen and subtract machine outlet gantry speed v _N ^kAnd the tandem rolling external diameter of pipe that reality is set is D _O ^dWith desirable tandem rolling external diameter of pipe D _O ^kUnanimity, promptly $D_0^d=D_0^k;$

Step 2. real-time online calculates tandem rolling thickness of pipe wall S _O ^k, and calculate its error;

Step 21. because $\frac{B_d}{B}=\frac{(D_0^d-S_0^d)S_0^d{L}_d}{(D_0^k-S_0^k)S_0^{k}L},$ And $D_0^d=D_0^k,$ Then have $\frac{B_d}{B}=\frac{(D_0^d-S_0^d)S_0^d{L}_d}{(D_0^d-S_0^k)S_0^{k}L},$ Promptly

${\left(S_0^k\right)}^2-D_0^d{S}_0^k+\frac{(D_0^d-S_0^d)S_0^d{L}_{d}B}{{\mathrm{LB}}_d}=0,$ Order $C=\frac{(D_0^d-S_0^d)S_0^d{L}_{d}B}{{\mathrm{LB}}_d},$ Then can calculate actual tandem rolling thickness of pipe wall S _O ^kFor: $S_0^k=\frac{D_d-\sqrt{D_d^2-4C}}{2};$

Step 22: according to desirable tandem rolling thickness of pipe wall S _d, calculate the error of actual tandem rolling thickness of pipe wall S, if error does not meet the demands, then go to step 4 earlier, carry out step 3 again; If error meets the demands, then continue only carry out step 3;

Step 3. subtracts the online adjustment of roll rotational speed of machine feedforward Self Adaptive Control;

Step 31.,, has for desired quantity and the actual numerical value that records under the stable rolling state by the constancy of volume rule according to the standard pass schedule:

$(D_0^d-S_0^d)S_0^d{\mathrm{\&phi;}}_0^d{v}_0^d=(D_N^d-S_N^d)S_N^d{\mathrm{\&phi;}}_N^d{v}_N^d,$

$(D_0^k-S_0^k)S_0^k{\mathrm{\&phi;}}_0^k{v}_0^k=(D_N^k-S_N^k)S_N^k{\mathrm{\&phi;}}_N^k{v}_N^k;$

And ${\mathrm{\&phi;}}_0^k\&ap;{\mathrm{\&phi;}}_0^d,{\mathrm{\&phi;}}_N^k{\&ap;\mathrm{\&phi;}}_N^d,$ $D_0^k\&ap;D_0^d,D_N^k{\&ap;D}_N^d;$

Can get thus: $\frac{(D_0^d-S_0^d)S_0^d{\mathrm{\&phi;}}_0^d{v}_0^d}{(D_0^d-S_0^k)S_0^k{\mathrm{\&phi;}}_0^d{v}_0^k}=\frac{(D_N^d-S_N^d)S_N^d{\mathrm{\&phi;}}_N^d{v}_N^d}{(D_N^d-S_N^k)S_N^k{\mathrm{\&phi;}}_N^d{v}_N^k},$ Promptly $\frac{(D_0^d-S_0^d)S_0^d{v}_0^d}{(D_0^d-S_0^k)S_0^k{v}_0^k}=\frac{(D_N^d-S_N^d)S_N^d{v}_N^d}{(D_N^d-S_N^k)S_N^k{v}_N^k};$

Step 32. because of $v_N^d=v_N^k,$ And for guaranteeing $S_N^k=S_N^d,$ The method that roll rotational speed is adjusted in the Self Adaptive Control of feedforward wall thickness is: $v_0^k=\frac{(D_0^d-S_0^d)S_0^d}{(D_0^d-S_0^k)S_0^k}{v}_0^d,$ Realize control automatically in real time;

The correction of step 4, calculating roll rotational speed: will $v_0^k=\frac{(D_0^d-S_0^d)S_0^d}{(D_0^d-S_0^k)S_0^k}{v}_0^d$ Write as increment type:

$v_0^k=v_0^d+\frac{(D_0^d-S_0^d-S_0^k)}{(D_0^d-S_0^k)S_0^k}{v}_0^d\mathrm{\&Delta;}{S}_0,$ Wherein $\mathrm{\&Delta;}{S}_0=S_0^d-S_0^k;$ Because the finishing frame mainly participates in the shaping of steel pipe, when carrying out wall thickness feed forward control, keep their roll rotational speed constant, and only allow tension force rise frame and work housing participation speed governing.If allow k-1 frame participate in speed governing, promptly the rotating speed of k frame is fixed, then following distribution respectively participates in the speed of the frame of speed governing:

$v_i^k=v_i^d+\frac{(v_k^d-v_i^d)(D_0^d-S_0^d-S_0^k)}{(v_k^d-v_0^d)(D_0^d-S_0^k)S_0^k}{v}_0^d\mathrm{\&Delta;}{S}_0,$ Obtain the correction of roll rotational speed, revise pass schedule.

2. feed forward control method for wall thickness of tension reducing machine as claimed in claim 1 is characterized in that, online feedforward self adaptation is adjusted in the process of roll rotational speed, and the adjustment of roll rotational speed scope is less than 10% of former rotating speed, and the adjustment trend of each frame rotating speed is consistent, promptly ${\mathrm{\&phi;}}_0^k\&ap;{\mathrm{\&phi;}}_0^d,{\mathrm{\&phi;}}_N^k\&ap;{\mathrm{\&phi;}}_N^d,$ $D_0^k\&ap;D_0^d,D_N^k{\&ap;D}_N^d.$

3. feed forward control method for wall thickness of tension reducing machine as claimed in claim 1 is characterized in that, online feedforward self adaptation is adjusted in the process of roll rotational speed, keeps the rotating speed of outlet running roller constant substantially, promptly $v_N^d=v_N^k.$

Images