یکی از رایج ترین ترموول های ترموکوپل تیوپ یا غلاف فلزی می باشد که بسته به نوع کاربرد،محدوده دما،محل قرارگیری تفاوت هایی با هم دارند که در این جا ما خصوصیات هریک از آلیاژ های پرکابرد را اشاره میکنیم تا بتوانید در انتخاب آنها دقت کافی برخوردار باشید:
۳۱۶ Stainless Steel
یکی از پرکاربردترین غلاف های فلزی استنلس استیل ۳۱۶ می باشد
Maximum temperature: 1650. Best corrosion resistance of the austenitic stainless steel grades. Widely used in the food and chemical
industry. Subject to damaging carbide precipitation in 900F to 1600F (482C to 870C
۳۱۶L Stainless Steel
Maximum temperature: 1650°F (900°C). Same as 316 SST (04) except Iow carbon version allows for better welding and fabrication
۳۰۴ Stainless Steel
Maximum temperature: 1650°F (900°C). Most widely used low temperature sheath material. Extensively used in food, beverage, chemical and other industries where corrosion resistance is required
Industry: Subject to damaging carbide precipitation in 900 to 1600°F (480 to 870°C) range. Lowest cost corrosion resistant sheath material available
۳۰۴L Stainless Steel
Maximum temperature: 1650°F (900°C). Low carbon version of 304 SST (02). Low carbon content allows this material to be welded and heated in the 900 to 1600°F (480 to 870°C) range without damage to corrosion resistance
۳۱۰ Stainless Steel
Maximum temperature: 2100°F (1150°C). Mechanical and corrosion resistance, similar to but better than 304 SS. Very good heat resistance
This alloy contains 25% chromium, 20% nickel. Not as ductile as 304 SS
۳۲۱ Stainless Steel
Maximum temperature: 1600°F (870°C). Similar to 304 SS except titanium stabilized for intergranular corrosion
This alloy is designed to overcome susceptibility to carbon precipitation in the 900 to 1600°F (480 to 870°C) range. Used in aerospace and chemical applications
۴۴۶ Stainless Steel
Maximum temperature: 2100°F (1150°C). Ferritic stainless steel which has good resistance to sulfurous atmospheres at high temperatures
Good corrosion resistance to nitric acid, sulfuric acid and most alkalies. 27% chromium content gives this alloy the highest heat resistance of any ferritic stainless steel
Inconel 600
Maximum temperature: 2150°F (1175°C). Most widely used thermocouple sheath material. Good high temperature strength, corrosion resistance, resistance to chloride-ion stress corrosion cracking and oxidation resistance to high temperatures
Do not use in sulfur bearing environments. Good in nitriding environments
Inconel 601
Maximum temperature: 2150°F (1175°C) continuous, 2300°F (1260°C) intermittent. Similar to Alloy 600 with the addition of aluminum for outstanding oxidation resistance. Designed for high temperature corrosion resistance
This material is good in carburizing environments, and has good creep rupture strength. Do not use in vacuum furnaces! Susceptible to intergranular attack by prolonged heating in 1000 to 1400°F (540 to 760°C) temperature range
Incoloy 800
Maximum temperature: 2000°F (1095°C). Widely used as heater sheath material. Minimal use in thermocouples. Superior to Alloy 600 in sulfur, cyanide salts and fused neutral salts
Susceptible to intergranular attack in some applications by exposure to the temperature range of 1000 to 1400°F (540 to 760°C)
