About the Thermometer-The Aluminum Billet Thermometer represents a major advance in the measurement of billet temperature. The thermometer is designed specifically to provide fast and accurate measurement of temperature on the cylindrical surface of billets - either a spot measurement or a complete lengthwise profile.
Why Measure Temperature?-Accurate data on process variables, particularly billet and die exit temperatures, enables modern process optimization and press control systems to achieve almost isothermal extrusion conditions. During Aluminum extrusion, optimum billet temperature and taper characteristics lead to reduced die wear and improved press efficiency. To obtain the ideal billet heater settings, a fast and reliable measurement of billet temperature prior to loading into the press is essential. The measurement system must also be able to cope with changes of alloy type and surface finish.
Problems Involved in the Traditional Approach-The most widespread method for measurement of billet temperature is the use of prodder thermocouples, either singly on an end face or in banks along its length.
Thermocouples are slow, maintenance intensive and inaccurate as metal build-up occurs on the tips. The cost in replacements and downtime is also significant. In addition, taper measurements are at best limited to between 6 and 8 points along the billet. Speed of response is important to avoid unnecessary delay between the measurement and loading of the billet into the press.
LAND Solution-The Aluminum Billet Thermometer System (ABT) utilizes unique, non contact emissivity enhancement technology to provide accurate results on all common alloys and surface conditions. Measurements are made on the curved surface of the billet. The thermometer can be mounted for a spot measurement on stationary billets or installed to scan the length of each billet as it exits the preheat furnace.