Foundry owners could be wasting money and operating inefficiently by failing to use an accurate and continuous method of measuring the temperature of molten metals in holding furnaces prior to casting.
That’s the warning from the Molten Metal Systems business of Morgan Advanced Materials, whose Blue Lightning Thermocouple Sheath delivers a reliable, contamination-free reading within five minutes, helping foundries to avoid overheating metals and reduce energy wastage. Available as a full thermocouple assembly, Morgan’s solution saves labour time, while its clay graphite construction delivers improved protection of metal purity over cast-iron thermocouple sheaths.
Consistent high temperatures are required in holding furnaces, where metals – notably aluminium – must be kept in a molten state prior to casting. Some foundries measure only the outer furnace temperature, while others do not measure the temperature at all. Either approach is inefficient as operators tend to overestimate the temperature required, and therefore spend more on energy.
For a more accurate measurement, thermocouple sheaths are dipped into the molten metal. The material traditionally used for this purpose, cast iron, has its drawbacks compared to the clay graphite used in the manufacture of Blue Lightning.
“Cast iron will quickly degrade, meaning sheaths have to be replaced regularly. There is also the risk of cross-contamination of iron particles mixing with molten aluminium. To prevent this, iron thermocouple sheaths are coated with a protective material; a daily process that wastes valuable foundry labour time,” explained Mirco Pavoni, Global Technology Director of Molten Metal Systems at Morgan Advanced Materials.
The answer from Morgan is the Blue Lightning Thermocouple Sheath manufactured in a special clay graphite construction. This material is neutral and inert, eliminating the risk of contamination and protecting the purity of the molten metal. Clay graphite also offers exceptional thermal shock resistance, meaning that Blue Lightning lasts considerably longer than cast-iron sheaths and can withstand temperatures up to 2 192 degrees Fahrenheit (or 1 200 degrees Celsius).
“Using Blue Lightning, an accurate reading can be achieved in just three to five minutes, faster than cast iron because of clay graphite’s superior conductive properties. This enables foundry operatives to adjust the temperature quickly, further reducing energy wastage,” says Mirco.
Morgan’s Molten Metals business supplies Blue Lightning as a full thermocouple assembly to support foundries looking for a single supplier. In tandem with Morgan’s expertise in advanced composite materials, this makes Blue Lightning a truly comprehensive system for the measurement of molten metal temperature.
“Two types of pyrometer are available to suit the specific setup of a foundry. Blue Lightning is equally accurate whether used with a fixed pyrometer, which measures the temperature towards the bottom of the crucible, or a floating pyrometer for applications where foundries take their molten metal from near the top,” confirmed Mirco.
For further information contact Morgan Advanced Materials Thermal Ceramics South Africa on TEL: 011 296 0000 or visit www.morgantechnicalceramics.com