KANTHAL® PM Tubes Radiant Tubes and KANTHAL

Company Information Kanthal is a world-renowned name within the field of electric heating. Since the early thirties, Kanthal has developed market leading, electric resistance alloy products and materials. Our R&D efforts have always been directed at improving our materials to function fully at ever higher temperatures. The center for production, product development and metallurgy is in Hallstahammar, Sweden, whilst sales and production finishing plants are located around the world, close to our customers and operated through our subsidiaries and local representatives. Kanthal is a Sandvik Company....

More Power, Longer Life and Less Maintenance Kanthal metallic PM material has been successfully used for many years in the form of wire, strip, radiant and protection tubes. Used mainly in the heat treat-ment, steel and aluminum industries, KANTHAL® PM tubes contribute to much higher furnace pro-ductivity by offering more power, less maintenance and longer service life. KANTHAL PM tube range includes APM (Advanced Powder Metallurgy), suitable for most types of processes, and APMT, an alloy with improved hot strength for extra demanding horizontal applications. KANTHAL PM tubes are suited to both...

Product Summary Ready to Install KANTHAL PM tubes are supplied as complte plug-in units for gas or electric furnaces. We can assist you in calculating and choosing the most suitable system for your particular needs. Tube systems are stocked in standard dimensions to fit most furnaces and to allow fast deliveries. Gas Heated Furnaces Straight Through Tubes . . Page 16 Recuperative SER Systems with Outer and Inner Tubes . Page 16 ECOTHAL® SER-burner, the Most Efficient Gas Solution on the Market . Page 18 Electrically Heated Furnaces TUBOTHAL® Metallic Heating Systems . . Page 20 GLOBAR" Silicon...

KANTHAL PM Material The Kanthal family of high temprature materials is aimed initially at the manufacture of resistance wire and strip for electric furnace applications. The KANTHAL PM (Powder metallurgy) materials, APM and APMT, are seamless and produced by extrusion. KANTHAL PM tubes are suitable for use in a wide range of temperatures and atmospheres, covering many applications and processes in various industries. KANTHAL PM materials are based on the well-known Kanthal FeCrAl alloy, the basis of electric elements in many different types of kiln and furnace for over 70 years. The PM materials...

High Temperature Strength Creep Rupture Strength KANTHAL PM tubes offer a unique combination of strength and corrosion resistance, which allows them to be used at higher temperatures than NiCr tubes and still exhibit a long working life. With KANTHAL APMT, tubes have similar strength values as NiCr tubes, but retain much of their strength up to temperatures well above the working temperature of NiCr tubes. [MPa] 100 Inconel 601 HP40 10 0.1 800 1470 850 1560 900 1650 950 1740 1000 1830 1050 1920 1100 2010 1150 2100 1200 2190 1250 2280 [°C] (°F) Fig. 1 Creep rupture strength - 10 000 h. Resistance...

and creep data. In the sagging test, the density of the tube material plays a larger role than in a creep test, where weights are applied independently of the alloy tested. Another factor is the change in deformation behaviour with time. All tubes show initially a higher deformation rate. After the initial sagging, the FeNiCr material follows a fairly linear behaviour with time. In the case of KANTHAL PM the deformation rate continues to decrease with time. This is often the experience in real applications. Rotat-ing tubes 180° at regular intervals is common practice in furnaces with welded or...

High Temprature Corrosion Properties KANTHAL PM alloys exhibit excellent high temp魩rature corrosion properties. The explanation for the excellent corrosion resistance is the formation of a dense, cohesive aluminum oxide layer on the surface protecting the base material from corrosion attack. This aluminum oxide, Al2O3, is formed through selective oxidation of the aluminum in the alloys. There are some criteria that an effective protective oxide must fulfil. ͕ Thermodynamically stable - The oxide should not be reduced or react in any other way with the surrounding atmosphere Adhըrent - The oxide...

has proved vastly superior to even the best grades of nickel chromium alloys. The graph below shows the comparison between KANTHAL APM and various nickel-chromium alloys, in terms of carburization rate versus temperature. The excellent results speak for themselves. severe form of localised carbon attack that normally occurs in a temperature interval between 500 and 900°C (930 - 1650°F). Even though this is a lower temperature range than would normally be used for APM/APMT materials, it has proven to resist attack much better than conventional grades. Rsistant to Sulphurous Atmosphres KANTHAL...

Maximum Recommended Tempratures The diagram below shows recommended maximum tempratures for different alloys in various atmo驭spheres. These temperatures are chosen from a prac-tical, industrial point of view, although the material can withstand higher temperatures if needed. For N2 and N2+H2 atmospheres, at low Dew Point (< -20°C (-4°F)), special considerations are needed. Please contact Kanthal for further information. (°F) [°C] (2550) 1400 Temprature ^^^^ ^ 饥 T W I T T X T - ŗ APM OC/OC - 601 ח 25/20 (2190) 1200 (1830) 1000 (1470) 800 (1110) 600 (750) 400 (390) 200 (32) 0 X. V V X v * Limitation...

Limitations of Conventional NiCr Alloys The majority of radiant tubes are manufactured from nickel-chromium, or iron-nickel-chromium alloys, produced by centrifugal casting, extrusion or fabrication from rolled sheet. The limiting factor for the use of these tubes is in most cases not strength, but poor resistance to high temperatures and/or aggressive atmospheres. The limitations in performance have confined their use to relatively low temperatures and power outputs. The limitations of NiCr alloys, operating in oxidiz-ing conditions, are due primarily to the formation of chromium oxide on the...