The EMLI Electromagnetic Level Measurement with Mold Mounted Sensors
EMLI System Description
The EMLI™ (Electro Magnetic Level Indication) system utilizes state-of-the-art technology in the measurement and detection of liquid metal levels. The basic EMLI system architecture consists of a MANAGEMENT UNIT, a CONTROL UNIT and a PREAMPLIFIER UNIT. In multiple system applications, one MANAGEMENT UNIT can monitor up to eight (8) CONTROL UNITS.
The MANAGEMENT UNIT is used to monitor the system, log data, and for set-up and troubleshooting. If enabled the system can be remotely evaluated through the MANAGEMENT UNIT via an Internet connection.
The CONTROL UNIT is the heart of the system. It generates the transmitter signal and receives and evaluates the measurement signal.
The PREAMPLIFIER UNIT increases the level of the measurement signal before it is fed to the CONTROL UNIT
EMLI - Mold Level Measurement System
The EMLI mold level measurement system with mold mounded sensors consists of a state-of-the-art electronics package combined with custom designed and steel mill proven electromagnetic metal level sensors.
In this system, the sensors, or cassettes are mounted directly on to the top of the copper of one on the broad face sides of the mold.
One major advantage of this type of arrangement is that the sensors are conveniently out of the operator's way. This means that changes of the submerged entry nozzle (SEN) or tundish flies do not require removal of the sensor and therefore the control system can remain in automatic control during these procedures.
The EMLI mold level measurement system with mold mounted sensors consists of two sensors, a transmitter sensor and a receiver sensor, that are mounted directly to the top of one of the molds' copper broad faces.
A regulated AC current is sent through the transmitter sensor. This current causes the transmitter to generate a magnetic field. This magnetic field induces eddy currents in the surface of the adjacent copper mold wall. The eddy currents product their own electromagnetic field which is detected by the receiver sensor.
When the metal level in the mold is low, more of the copper wall is exposed and more eddy currents are generated resulting in a larger magnetic field and a stronger received signal.
When the metal level in the mold is high, the copper is shielded by the liquid metal and the amount of eddy currents produced is diminished. This results in a smaller magnetic field and a weaker received signal.
The EMLI mold level measurement system with mold mounted sensors offers the following benefits: