阅读说明：本技术 一种提高热轧钢板瓢曲性能的超快冷方法 (Ultrafast cooling method for improving buckling performance of hot-rolled steel plate ) 是由 李文刚 牟凯 李敬民 张军冬 于 2021-08-31 设计创作，主要内容包括：本发明公开了一种提高热轧钢板瓢曲性能的超快冷方法,其特征在于：在设置头尾遮蔽距离和系数后,设置头部遮蔽时间t；所述头部遮蔽时间t为流量提升开始至钢板头部进入超快冷的时间,且0<t<t-(1)+t-(2)；其中,t-(1)为阀响应时间,t-(2)为流量达到目标值时间。所述头部遮蔽时间t=t-(0)+Δt；其中,t-(0)为初始设定值,Δt为调整值,Δt与钢板出水后黑头的长度L-(黑)或红头的长度L-(红)关系如下：Δt=—0.1*(L-(黑)/100)或Δt=0.1*(L-(红)/100)。本方案通过增设时间调整参数,有效的解决了在超快冷过程中,因阀相应、流量爬升过程对钢板冷却质量的影响,提高了钢板头尾和板身温度的均匀性,降低钢板头尾瓢曲量,提高了产品的质量。(The invention discloses an ultra-fast cooling method for improving buckling performance of a hot-rolled steel plate, which is characterized by comprising the following steps of: after the head-tail shielding distance and the coefficient are set, the head shielding time t is set; the head shielding time t is the time from the beginning of flow lifting to the time when the head of the steel plate enters into the ultra-fast cooling, and is 0<t<t 1 +t 2 (ii) a Wherein, t 1 As valve response time, t 2 The time for the flow to reach the target value. The head shielding time t = t 0 + Δ t; wherein, t 0 Is an initial set value, delta t is an adjustment value, and delta t is the length L of the blackhead after the steel plate is drained Black colour Or length L of red head Red wine The relationship is as follows: Δ t = -0.1 = (L) Black colour /100) or Δ t =0.1 (L) Red wine /100). This scheme is through addding time adjustment parameter, and effectual solution is at the ultrafast cold in-process, because of the valve is corresponding, the flow process of climbing to the influence of steel sheet cooling quality, has improved the homogeneity of steel sheet head and tail and plate body temperature, reduces the steel sheet head and tail and buckles the volume, has improved the quality of product.)

1. An ultra-fast cooling method for improving buckling performance of a hot-rolled steel plate is characterized by comprising the following steps: after the head-tail shielding distance and the coefficient are set, the head shielding time t is set; the head shielding time t is the time from the beginning of flow lifting to the time when the head of the steel plate enters into the ultra-fast cooling, and is 0<t<t₁+t₂(ii) a Wherein, t₁As valve response time, t₂The time for the flow to reach the target value.

2. The ultra-fast cooling method for improving buckling performance of hot rolled steel plate according to claim 1, characterized in that: the head shielding time t = t₀+ Δ t; wherein, t₀Is an initial set value, delta t is an adjustment value, and delta t is the length L of the blackhead after the steel plate is drained_{Black colour}Or length L of red head_{Red wine}The relationship is as follows:

Δt=—0.1*（L_{black colour}/100) or Δ t =0.1 (L)_{Red wine}/100）。

Technical Field

The invention belongs to the technical field of metallurgical manufacturing, and particularly relates to an ultra-fast cooling method for improving buckling performance of a hot-rolled steel plate.

Background

In recent years, with the development requirement of thin-gauge low-temperature water-cooled steel plates, higher requirements are put on cooling technology in the aspects of cooling speed, cooling uniformity and the like, and the new-generation multifunctional medium plate post-rolling cooling technology characterized by ultra-fast cooling can meet various cooling process requirements, and has become a development trend of the medium plate post-rolling cooling technology at home and abroad.

However, in the existing process, the steel plate after water cooling by the ultra-fast cooling device usually has uneven water cooling of the head and the tail, such as black head lower buckle, red head upwarp, and the like. The continuous production under the water cooling condition is limited by the head and tail shielding hard damage, the head and tail of the steel plate are seriously buckled and even can reach 27 percent of the curvature of the steel plate, the product quality is seriously influenced, the cold straightening or saving process is forced to be additionally added, and the production requirement cannot be well met.

Disclosure of Invention

The invention aims to provide an ultra-fast cooling method for improving buckling performance of a hot-rolled steel plate, which aims to solve the problems in the prior art.

The invention is realized by the following technical scheme: an ultra-fast cooling method for improving buckling performance of a hot-rolled steel plate is characterized by comprising the following steps: after the head-tail shielding distance and the coefficient are set, the head shielding time t is set; the head shielding time t is the time from the beginning of flow lifting to the time when the head of the steel plate enters into the ultra-fast cooling, and is 0<t<t₁+t₂(ii) a Wherein, t₁As valve response time, t₂The time for the flow to reach the target value.

Further: the head shielding time t = t₀+ Δ t; wherein, t₀Is an initial set value, delta t is an adjustment value, and delta t is the length L of the blackhead after the steel plate is drained_{Black colour}Or length L of red head_{Red wine}The relationship is as follows:

Δt=—0.1*（L_{black colour}/100) or Δ t =0.1 (L)_{Red wine}/100）。

The invention has the advantages that: according to the invention, by additionally arranging the time adjustment parameter, the time difference caused by the process that the valve is opened correspondingly and the flow reaches the target value in the ultra-fast cooling process is effectively solved, the influence of the flow climbing process on the cooling quality of the steel plate is reduced, and the temperature uniformity of the head and the tail of the steel plate and the temperature uniformity of the plate body are improved. According to the method, time adjustment parameters are added on the basis of the original head and tail shielding adjustment distance and water flow coefficient, and in the climbing stage of a water flow curve, any time parameter within 0-6 seconds is selected through adjustment of the head and tail shielding time, and a head flow lifting signal is triggered in advance, so that the purpose that the head of each specification of steel plate needs the flow parameters is achieved, the head and tail buckling amount of the steel plate is reduced, and stable execution of the process is ensured.

Detailed Description

The invention provides an ultra-fast cooling method for improving buckling performance of a hot-rolled steel plate, which is characterized in that when a steel plate is cooled in an ultra-fast cooling mode, after head and tail shielding distances and coefficients are set, the head shielding time t is also increased; the head shielding time t is the time from the position of the steel plate to the time when the head of the steel plate enters into the ultra-fast cooling process when the flow lifting starts, namely, the steel plate enters into the flow climbing stage when the steel plate is at the position. In this scheme, the range of the head shielding time t is as follows: 0<t<t₁+t₂(ii) a Wherein, t₁As valve response time, t₂The time when the flow rate reaches the target value, i.e., the time when the flow rate reaches the maximum value (usually 1) from the set flow rate coefficient.

Preferably: the head shielding time t = t₀+ Δ t; wherein, t₀Is an initial setting value, and 0< t₀<t₁+t₂(ii) a Delta t is an adjusting value and is modified and adjusted according to the state of the steel plate after water is discharged, wherein the delta t and the length L of the blackhead of the steel plate after water is discharged_{Black colour}Or length L of red head_{Red wine}The relationship is as follows:

Δt=—0.1*（L_{black colour}/100) or Δ t =0.1 (L)_{Red wine}/100）。

In this embodiment, the length is in mm and the time is in s.

Examples

1) First, head and tail shielding parameters are set.

For a steel plate with certain specification, the parameters are as follows:

head distance and head flow upper coefficient/lower coefficient =400 x 0.3/0.3;

tail distance and tail flow upper coefficient/lower coefficient =800 × 0.4/0.4;

head shade time 2. Where valve response time 1 and flow ramp time 6.

In the scheme, the valve response time is a parameter of the valve, and can be specifically determined according to different valves. The flow rate rising time is a time from a set flow rate coefficient to a time when the valve is opened, the coefficient is a maximum value (usually 1), for example, in this embodiment, a head is taken as an example, the flow rate is increased from 30% to 100%, a flow rate curve of a cooling process is approximately in a shape of a Chinese character 'ji', the time is a time taken from an initial low flow rate to a maximum flow rate, and the flow rate rising time is approximately a steep slope rising in the curve, so the flow rate rising time is called as usually 6.

2) Under the above parameter condition, if the steel plate is blacked out, the time parameter should be reduced, and each time the adjustment is 0.2. I.e. the time parameter is adjusted to 1.8/1.6/1.4/1.2/1.0, etc. The adjustment range can be increased according to the distance of the blackheads, the blackheads are 200mm, the time parameter is adjusted according to 0.2s, and the time parameter is adjusted by 0.1s every time the blackheads are increased by 100 mm.

3) Under the above parameter state, if the steel plate is red when water is discharged, the time parameter should be increased and adjusted by 0.2 each time. I.e. the time parameter is adjusted to 2.2/2.4/2.6/2.8/3.0, etc. The adjustment amplitude can be increased according to the distance of the red head, the red head is 200mm, the time parameter is adjusted according to 0.2, and the time parameter is adjusted by 0.1 when the red head is increased by 100 mm.

4) In the adjusting process, the range of the time parameter of the certificate is always qualified, and if the adjusting effect of the time parameter is not obvious in the corresponding range, the head and tail shielding distance and the water flow coefficient need to be adjusted in time.

In conclusion, in order to solve the buckling problem of the head and the tail of the steel plate, in the ultra-fast cooling system, the corresponding time of the water extraction valve and the time when the water flow reaches the target value are adopted. And according to the time length of the water flow curve in the climbing stage, adding time adjustment parameters in a head-tail shielding program, setting different time parameters according to different specifications, and eliminating buckling of the head black lower buckle and the head red upper buckle. According to the scheme, the head and tail shielding distance and coefficient are firstly solidified according to specifications, then the head and tail shielding time parameter adjustment is carried out, the head and tail shielding distance and coefficient adjustment in the later period is preferentially carried out according to the head and tail shielding time parameter adjustment, in the whole process, the head and tail shielding time parameter can be adjusted according to the actual water cooling condition of the head and the tail of the steel plate, the adjustment is flexible, the adaptability is good, and the control effect on the head and tail buckling of the steel plate is effectively improved.