Automation in Metal

The Low-tension time-sharing control method was first proposed and successfully applied in China to solve the problem of the control of the bar product size (including the head-to-tail size) for large- and medium-size bars in the no-loop production environment.

Core technology: precise rolling line tracking, accurate measurement of free rolling torque, timing control and time-sharing control of control process;

Control accuracy and speed: By controlling the input of low-tension control, it needs 2 to 3 billets to achieve a stable low-tension deviation within 2N/mm2, which meets the tolerance need in production.

Reference Applications: bar production lines in Hangang Gruoup (Shaanxi, China),  Yangchun New Steel (Guangdong, China),  Baote Shaoguan Steel (Guangdong, China).

Out control solution is the first successful application in China which adopts the control of lift-fall process together with the looper control system to control the stability of processing in bar finish milling, pre finish milling and finish milling zones, especially the problem of the dimensions of head and tail steels.

Core technology: precise bite（metal in stand） and steel signal acquisition and front and rear sliding measurement technology, safe and accurate looper pre-lift control, control of lift-fall (compensation control), variable proportional integral coefficient control in the height control, optimized control of floating loop.

Control accuracy: the length of the head and tail steel caused by lifting a loop is less than 2 meters, and those of other parts meet the production needs of one set of tolerances (half of one set of tolerance).

Reference Applications: High-line production in Chunqing Steel, Desheng 1 bar production line, Shaoguan Steel special bar production line.

In high-speed bar processing zones (3# or downstream flying shears used) we adopt robust flying shear control technology to stabilize the flying shear in the variation range under 100mm. In low-speed zones (1# and 2# flying shears used) the laser length measuring technology is first used so that the cutting head, cutting tail and double-foot precision of the flying shear are stabilized in the range less than 50mm.

Reference Applications: bar production line in CHunqing Steel, Desheng 1 bar production line, Shaoguan Steel special bar production line.

First application in China which applies non-baffle automatic length control to hydraulic shears.

Reference Applications: Large-size bar production line in Baote Shaoguan Steel (Guangdong, China)

The vertical rolling mills usually use a motor-drive gear to switch the roll, which is prone to damage in operation. The innovative vertical lifting control and protection rack is developed for solving this problem, which has the following functions: the rack operates normally when there is no jamming. While there is jam, the mechanism of scaling down the torch works so that the lifting device will not withstand the impact load exceeding the set range, thereby protecting the equipment from damage and prompting the operator to check the situation.

Reference Applications: large- an medium-size bar production lines in Baote Shaoguan steel (Guangdong, China)

1. Stable and accurate roll-feeding head jump control solution Importance and significance: it can greatly reduce the impact of the strip head on the equipment of the coiler and the wrapper roll, effectively extend the service life of the equipment and improve the surface quality of the strip head. Acceptance figure: at a distance of 10 meters from the coiler, the head noise should be reduced by more that 10db at a rolling and stepping speed of 10 m/s.

2. Tail automatic stop Importance and significance: reduce the operational differences caused by difference levels of operators, prevent the roll-out of the milling tower or the tail after finishing rolling, and protect the equipment. Acceptance figure: More than 99% success rate, parking error is less than 15o, or positioning precision (accuracy) is less than ±2%.

3. Actual roll diameter monitoring and prevention after tension setup Importance and significance: prevent the failure caused by early second increasing of the roll diameter, and the unloading difficulty caused by later increasing of roll diameter. Acceptance figure: the servo system and position sensor are used for the roll diameter increasing and decreasing. The diameter variation is less than 1mm. This variation is usually more than 3mm when a normal hydraulic device is used or there is no position sensor.

4. Constant-tension rolling in acceleration and deceleration Importance and significance: in order to protect the equipment and stabilize the rolling, advanced strip production line adopts the processing model of low-speed belting, high-speed rolling and low-speed polishing. All of them require constant-tension rolling in both acceleration and deceleration. Acceptance figure: the variation between the actual and the set value of tension should be smaller than 0.5 N/mm2.

Strip steel products produced by continuous rolling technology tend to be thin (thickness less than 2mm) and ultra-thin (thickness of 0.8-1.2mm, and 0.6-0.8mm in the future).

The thin hot-rolled steel strips as materials can reduce the number of cold-rolling and production cost as well. Ultra-thin hot-rolled strip can open new uses and new markets, and some products can replace cold-rolled strip, bringing huge economic benefits to manufacturers and users.

For high value-added continuous rolling products such as stainless steel, automobile sheet and silicon steel, by monitoring the state or the roller table, surface scratching cab be avoided in time, and the roller state prediction and active maintenance are possible. It can also improve the equipment on-line rate, reduce downtime and improve the product surface quality.

Core Technologies:
In-house developed ”current meter of frequency conversion roller motor”, efficiently and accurately measures the current of variable frequency roller motor.
In-house developed “on-site monitoring and display unit of frequency conversion roller motor”, performs on-site monitoring and display relevant current information.
In-house developed “roller state presentation and analysis system”, displays data in a vivid way, which is convenient for workers to know the state of the equipment. All the data is stored in the database for later statistic and analysis.