Reell Engineering Company has successfully implemented radio identification of products passing through furnace.
The production process of painting and drying of products includes passing of the overhead pusher conveyor traverses through a furnace with an air temperature of 310℃.
The Siemens MDS D139 heat-resistant HF tags with operating temperatures up to 220℃ are used for traverse identification.
First of all, a laboratory experiment was carried out to identify how temperatures exceeding the maximum operating temperature would affect the tag.
As a result of the experiment, it was revealed that at temperatures above 230℃, the transponder of the tag became damaged, at temperatures over 280℃ the tag body material became soft and at temperatures over 300℃ the tag body material melted.
Photos of the experiment results are provided in the table
| 220℃ | 230℃ | 240℃ | 250℃ | 260℃ |
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| 270℃ | 280℃ | 290℃ | 300℃ | 310℃ |
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Based on the results of the experiment, it was concluded that it was impossible to use the standard solution under high temperature conditions.
An outer casing made with a special SiO2-based heat-insulating fabric with a melting point of 1000℃ was designed and manufactured.
Temperature tests with the tag inside the casing showed that the tag’s transponder remained operational after being in the furnace at the temperature of 320℃. Neither the casing nor the tag received any damage, except for discoloration of the casing material.
| 220℃ | 320℃ |
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Next, it was necessary to find out how the use of outer casing affected the reading range of the tags.
The maximum reading range for the Siemens MDS D139 tag was measured at 65 mm using the RF260R reader.
The maximum reading range for the Siemens MDS D139 tag inside the thermal protective casing was 54 mm using the RF260R reader and, taking into account the casing material thickness of 6 mm, the reading range of the tag was 60 mm, which demonstrated the possibility of using covers with a slight deterioration in the reading range.
Based on the test results, more than 600 casings for the Siemens MDS D139 tags were manufactured and installed on the traverses of an overhead pusher conveyor of a painting line for vehicle parts. Tags inside the thermal protective casings have been successfully used for more than 1 year as of summer 2020.
We invite you to use the Reell Engineering competencies in high temperature object radio identification, as well as the competencies in RFID and OID Software Development.