Speed control method in steel rolling process

Abstract

The invention discloses a speed control method in a steel rolling process, which specifically comprises the following steps of: 1, setting rolling parameters of K1-Kn rolling mills according to production parameters, and forming a speed cascade relationship between racks; 2, a rolled piece enters rolling work from K1; 3, after the Kn steel biting current signal is obtained, the speed of the Kn rolling mill is automatically increased for several ms on the basis of the set value, and then the speed is reduced to the set value; step 4, after the tail part of the rolled piece goes out of Km-1, the speed of Km is automatically reduced on the basis of setting until the tail part of the rolled piece goes out of Km and then recovers to a set value; and 5, after the tail of the rolled piece comes out of Kn-1, the speed of Kn is automatically reduced on the set basis until the tail of the rolled piece is separated from a Kn rolling mill and then recovered to a set value, and automatic speed control over the head and tail of the rolled piece is achieved to improve the large size of the head and tail of the deformed steel bar.

Description

Technical Field

[0001] The present invention relates to the technical field of steel rolling processes, and particularly to a speed control method in a steel rolling process. Background Art

[0002] When producing small-sized deformed steel bars, the rolled piece generates an impact load during steel feeding, which causes the speed to decrease instantaneously, resulting in a stacked state between the rolled pieces and causing the head size of the steel bar to be too large; in the rough rolling area, there is no loop device between the stands, and the tension disappears after the rolled piece exits the stand, which also causes the tail size of the steel bar to be too large. This will result in the phenomenon that the entire length of the steel bar has a large head and tail and a small middle part. In severe cases, the head and tail sizes exceed the national standard requirements. During production, only by increasing the waste cutting amount at the head and tail can the product quality be ensured, which seriously affects the economic benefits of production enterprises. Summary of the Invention

[0003] The purpose of the present invention is to provide a speed control method in a steel rolling process for the deficiencies of the prior art.

[0004] The technical solution of the present invention to solve the above problems is: a speed control method in a steel rolling process, including n rolling mills, namely K1 - Kn, where K1 is the starting rolling mill, Kn is the finishing pass rolling mill, K1 - Km is rough rolling, and Km - Kn is finish rolling, 0 < m < n, and it is characterized in that:

[0005] Specifically, it includes the following steps:

[0006] Step 1, set the rolling parameters of each rolling mill of K1 - Kn according to the production parameters, and form a speed cascade relationship between the stands;

[0007] Step 2, the rolled piece enters the rolling operation from K1;

[0008] Step 3, after obtaining the biting current signal of Kn, the speed of the Kn rolling mill automatically increases by 2% on the basis of the set value and lasts for 100 ms, and then drops back to the set value;

[0009] Step 4, after the tail of the rolled piece exits Km - 1, the speed of Km automatically decreases until the tail of the rolled piece exits Km and then returns to the set value;

[0010] Step 5, after the tail of the rolled piece exits Kn - 1, the speed of Kn automatically decreases until the tail of the rolled piece disengages from the Kn rolling mill and then returns to the set value.

[0011] Further, the production parameters in Step 1 include the material type, roll diameter, and second flow rate.

[0012] Further, in Step 3, after obtaining the biting current signal of Kn, the speed of the Kn rolling mill automatically increases by 2% on the basis of the set value and lasts for 100 ms, and then drops back to the set value.

[0013] Furthermore, in step 4, after the tail of the rolled piece is out of Km-1, the Km speed is automatically reduced by 1% based on the setting until the tail of the rolled piece is out of Km and then restored to the set value.

[0014] Furthermore, in step 5, after the tail of the rolled piece leaves Kn-1, the Kn speed is automatically reduced by 2% based on the setting until the tail of the rolled piece leaves the Kn rolling mill and then returns to the set value.

[0015] The present invention has the beneficial effects:

[0016] The present invention provides a speed control method in a steel rolling process, which uses the current signals of the steel biting and steel stripping of the rolling mill to construct the speed-up and speed-down adjustment relationship of the rolling mill, and speeds up the rolling mill before the rolled piece bites in to compensate for the speed reduction value of the instantaneous steel biting. After a period of time, the speed compensation is cancelled to eliminate speed fluctuations. At the same time, the rolling mill is decelerated before the rolled piece is stripped until the rolled piece is stripped from the rolling mill, and the tension between the upstream and downstream frames before the rolled piece is stripped is increased to compensate for the tension lost after the tail of the rolled piece is stripped, thereby effectively reducing the head-tail difference of the steel bar. DETAILED DESCRIPTION

[0017] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0018] A speed control method in a steel rolling process is used to produce φ10 threaded steel bars, including 18 rolling mills, namely K1-K18, K1 is a starting rolling mill, K18 is a finished pass rolling mill, K1-K6 are rough rolling, and K7-K18 are finishing rolling.

[0019] The specific steps include:

[0020] Step 1: Set the rolling parameters of each rolling mill K1-K18 according to the material type, roll diameter, flow rate per second and other parameters, and form a speed cascade relationship between the stands. The rolling parameter settings of each rolling mill K1-K18 are shown in Table 1:

[0021] Table 1

[0022]

[0023] Step 2, the rolled piece enters the rolling process from K1;

[0024] Step 3, after the K18 steel biting current signal is obtained, the speed of the K18 rolling mill is automatically increased by 2% based on the set value, and lasts for 100ms after the rolled piece bites into the K18 rolling mill, and then drops back to the set value;

[0025] Step 4, after the tail of the rolled piece exits K5, the speed of K6 is automatically reduced by 1% based on the setting, and after the tail of the rolled piece exits K6, the speed of K6 is restored to the setting value;

[0026] Step 5, after the tail of the rolled piece leaves K17, the speed of K18 is automatically reduced by 2% based on the setting, and after the tail of the rolled piece leaves K18 rolling mill, K18 rolling mill returns to the setting value again.

[0027] The automatic speed reduction of the last rolling mill of rough rolling and the rolling mill of the finished pass can compensate for the tension lost after the rolled piece leaves the rolling mill, eliminating the influence of the large tail of the steel bar; the speed increase of the rolling mill of the finished pass can compensate for the speed reduction caused by the biting of the rolled piece, making the speed of the rolled piece stable and eliminating the influence of the large size of the steel bar head.

[0028] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A speed control method in a steel rolling process, including n rolling mills, namely K1 - Kn, where K1 is the starting rolling mill, Kn is the finishing pass rolling mill, K1 - Km is rough rolling, and Km - Kn is finish rolling, with 0 < m < n, characterized in that: Specifically, it includes the following steps: Step 1, set the rolling parameters of each rolling mill from K1 to Kn according to production parameters and form a speed cascade relationship between stands; Step 2, the rolled piece enters the rolling operation from K1; Step 3, after obtaining the current signal of Kn biting the steel, the speed of the Kn rolling mill automatically increases by a certain percentage on the basis of the set value and lasts for several milliseconds, and then drops back to the set value; Step 4, after the tail of the rolled piece exits Km - 1, the speed of Km automatically decreases on the basis of the set value until the tail of the rolled piece exits Km and then returns to the set value; Step 5, after the tail of the rolled piece exits Kn - 1, the speed of Kn automatically decreases on the basis of the set value until the tail of the rolled piece leaves the Kn rolling mill and then returns to the set value.

2. The speed control method in a steel rolling process according to claim 1, characterized in that: The production parameters described in Step 1 include the material type, roll diameter, and second flow rate.

3. The speed control method in a steel rolling process according to claim 1, characterized in that: In Step 3, after obtaining the current signal of Kn biting the steel, the speed of the Kn rolling mill automatically increases by 2% on the basis of the set value, lasts for 100 ms, and then drops back to the set value.

4. The speed control method in a steel rolling process according to claim 1, characterized in that: In Step 4, after the tail of the rolled piece exits Km - 1, the speed of Km automatically decreases by 1% on the basis of the set value until the tail of the rolled piece exits Km and then returns to the set value.

5. The speed control method in a steel rolling process according to claim 1, characterized in that: In Step 5, after the tail of the rolled piece exits Kn - 1, the speed of Kn automatically decreases by 2% on the basis of the set value until the tail of the rolled piece leaves the Kn rolling mill and then returns to the set value.

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