U and W shaped radiant tubes

U and W shaped radiant tubes for tube temperatures up to 1250°C (2280°F). The Kanthal program of radiant tubes includes nickel-chromium (NrCr) alloys or Kanthal APM and Kanthal APMT iron-chromium-aluminium (FeCrAl) alloys for extremely demanding environments, of combinations of the two material types.
Read more about Kanthal APM and Kanthal APMT FeCrAl alloys

Maximum tube temperature recommendations

* 353 MA and 253 MA are trademarks owned by Outokumpu OY.

The flexibility in choice of material means that Sandvik can offer the optimal tube design for practically any furnace atmosphere, process temperature and/or installation design. Our offer includes:

Radiant tubes for very high temperatures and severe conditions
Radiant tubes for tougher conditions at the burner leg
Radiant tubes for medium high temperatures

High-temperature corrosion properties
Material In air / oxidizing Oxidizing sulphur Reducing sulphur Carburizing Nitriding
ASTM 310 0 0 0 0  0
253 MA1) + + ++ +  02)
353 MA1) + - 0 ++ ++
Kanthal APM ++ ++ ++++ +++ +3)
Kanthal APMT ++ ++ ++++ +++ +3)

1) 253 MA and 353 MA are trademarks owned by Outokumpu OY

2) Nitriding may occur at very low dew point (<-60°C/-51°F)

3) Severe nitriding may occur at low dew point (<-20°C/-29°F)

Oxidation properties at 1100ºC (2040ºF)

Carburization rate for various alloys