Steel plants achieve efficient and fault-free production processes with effective logistics concepts. Every steel plant has its own production cycle. However, there is one principle that unites them: Every stage of the process moves things forward. That is, they should not slow down the process, or cause capacity blockages.
This efficiency poses a major challenge for the complex steel industry because every process must lead perfectly into the next, like gears in a gearbox. A steel plant is said to be fast if it requires only four hours running a full production process, from receiving raw materials to loading the finished product (and this still involves handling the product at least five times in the interim).
Therefore, one can imagine how complex and time-consuming the production processes used by “mega steel plants” are. A single plant may use an assortment of different steel-making techniques and produce several thousand types of steel, posing a considerable challenge for the plant management team, the staff, machines, and logistics structures.
Because companies produce different billets, blocks, sheets, wires, and pipes in an assortment of different lengths, widths, heights, and weights, the entire plant has to run like clockwork.
However, over the past few decades, the steel industry has managed to implement a number of technical innovations that have helped plants to reduce the cost of the production and improve the quality of its products, while still managing to increase process flexibility. When it comes to increasing the competitiveness of an individual plant however, internal processes such as the logistics chain and production cycles often play a decisive role.
Monitor, control, and regulate
Sensor solutions enable staff to communicate clearly and efficiently with machines, help to avoid risks and disruptions, and create more streamlined handling and logistic processes. There is almost no end to the new challenges facing the area of logistics, both when it comes to the delivery of materials, and storing and transporting final products.
The harsh environment does not make measurement requirements easier either. Faced with dirt, heat, vibrations from production systems, and a variety of different heavy goods vehicles, sensor solutions have to be extremely reliable, durable and robust. A high level of reliability and durability is crucial in sensor technology, while still ensuring that solutions are accurate and easy to use.
Providing a reliable solution for monitoring the entire production chain, they enable steel companies to automate repeated processes, which in turn help to improve the quality of the final product and increase safety standards. In the event that something does change in the process, the sensors have to be adapted to the new situation. By simply adjusting the settings, users can quickly retrieve customised limits or redefine parameters.
For example, if the traceability of goods has been improved and preventative maintenance measures have been added for production materials in the logistics chain, the processes themselves have to be well designed and transparent.
On the trail of materials
Tracking and tracing starts from the moment raw material is delivered and therefore helps to define one of the key challenges facing a plant’s internal logistics concept: streamlined storage. Companies have to know how much material they have at all times. Whether they have enough piece goods or bulk materials or gas in storage. Whether it is ore, coal, scrap, oxygen, nitrogen, specific alloying agents, or water.
Tracking material deliveries using wireless high frequency and ultra high frequency RFID technology is ideal for creating a transparent logistics concept. By applying quick measurement cycles (even over larger sensing ranges), the sensors automatically provide precise location data for cranes and railway carriages. Even in difficult conditions, the sensors present a high level of availability and a long service life. It is the perfect combination of measurement certainty and economic efficiency both inside and out.
Improving productivity safely and securely
Production determines the rhythm of the plant and thus poses the next big challenge facing the logistics concept in a steel mill: always having exactly the right amount of material at exactly the right time. The majority of production processes are not usually linear, while transportation routes often crisscross the entire plant.
Plants also often contain a number of different production lines that produce the same product in a variety of different dimensions, making the coordination process even more complex. Some intermediate goods and materials have to be stored during the course of the process. Transport containers like ladles and buckets have to be set up, crane processes have to be adjusted, and automatic vehicles have to fit the application. For this to succeed, the sensor technology used has to be accurate.
The larger the machine in question, the more difficult it is to keep track of the logistic details. Whether they use optoelectronic or ultrasonic technology, sensors solve the task. During the coil manufacturing process, for instance, distance sensors can detect the exact position of a gripper arm to the nearest μm without making contact, even for small scanning ranges.
Their measurement processes are integrated straight into the production process and provide a high level of repeatability, thus ensuring that the machines work properly and guaranteeing quality of the finished products, all for a low investment cost. Journey speeds can also be increased thanks to precise positioning using distance measurement devices. This solution provides quick access to materials without putting people or machines at risk. Furthermore, sensors enable companies to make more efficient use of interim storage spaces.
Increasing production output with more sensor solutions
Automation helps to streamline work processes so that the correct amounts of materials are available at each stage of the production process, delivered in order to the right processing unit. When using gases and liquids, engineering and process control solutions are crucial for pipeline systems and have to be adjusted to other material and energy flows.
Belt capacities must not be exceeded, which is why the laser technology in sensors like the Bulkscan LMS511 are able to measure both the volume and mass flow, based on detected densities. Able to withstand any belt vibrations, weather conditions and contamination, the Bulkscan transmits measurement data on the filling level and the center-of-gravity, which prevents material blockages and minimum capacity levels.
No automation without monitoring
Forklifts and rollers are used to transport billets, slabs and blocks, sometimes when they are still red hot. The solutions used for capturing, positioning and detecting therefore have to be suitably rugged.
For example, the WT45 photoelectric proximity switch senses the precise location of the material on the roller table, helping to streamline the manufacturing process. Thanks to a thermal shield and water-cooling system, presence detection is also reliable in hot conditions. Providing a high level of measurement accuracy, short-range OD distance sensors are used for checking, sorting, and inspecting objects in quality- and cost-relevant applications.
A number of different sensor heads for various precision ranges provides accurate measurements for height profiles and material thicknesses such as for quality control of the thickness such as metal strip. OD distance sensors for example are able to achieve measurement and output rates of up to 10kHz, perfect for use in high-speed applications.
Straight to the customer
Once the finishing process is complete, one is left with the final product, ready to be dispatched in accordance with the end customer’s specifications. Here, the various sizes, weights, and means of transport play a vital role, and depending on the product, the delivery is also tracked so that it can be traced at a later stage.
SICK Pty Ltd