LGO heating elements for tube furnaces

Koyo Thermo Systems is represented in Europe by
Crystec Technology Trading GmbH

LGO Heating Element for tube furnaces

Koyo Thermo Systems Ltd. is a manufacturer  of Light Gauge Overbend (LGO) heating elements, but can also supply standard Heavy Gauge Coil (HGC) heaters. The LGO heater is constructed in a totally different way. On these pictures you can see the differences:

LGO heating element

HCG heater

LGO

HGC

The patented LGO heating element is of low weight and has a thermal mass that is <50% of equivalent industry heating elements:


Weight (kg)

Thermal Mass

(kcal/°C)

Material

---LGO---

Standard

---LGO---

Standard

Shell

10.9

26.6

2.6

4.7

Insulation

17.4

14.7

4.6

4.2

Support

0

10.3

0

2.0

Heater

4.6

24.3

0.5

2.7

Total

32.8

75.9

7.7

13.6

The excellent temperature homogeneity results in a very long flat zone

flat zone

and in a very good radial temperature uniformity

radial temperature distribution

Comparing the two different types of heating elements available from Koyo Thermo Systems, the LGO heater reacts much quicker on controller commands and therefore you can avoid almost completely overshooting. This is especially true for "low temperature" applications, like polyimide bake, hydrogen anneal or SOG:

overshoot

It is possible, to retrofit an LGO heating element to existing furnaces.