Protective Gas Boxes with additional Vacuum Lid for Models N 7 - N 161

Protective gas box for N 41/H furnace with additional vacuum lid

Working with Protective Gas Boxes with additional Vacuum Lid to ensure Protective Gas Atmosphere

When heat treating bulk goods and hollow parts under defined protective gas atmosphere we recommend the usage of protective gas boxes with an additional vacuum lid. Thus the traces of oxygen in the box can be reduced by a considerable amount which improves the quality of the components accordingly. These boxes are equipped with a lid for top charging, protective gas inlet and outlet as well as a vacuum lid with rubber sealing gasket. Gas ductwork and handling while hot is the same as the protective gas boxes described on page 11. In addition, these boxes also feature a connection for a vacuum pump with a shut-off valve. After charging the box in a cold state it is brought into vacuum and afterwards flushed with protective gas. By repeating this process once or several times the results are considerably improved. After the box was flushed with protective gas the last time, the vacuum lid is removed and the box is placed into the preheated furnace. Protective gas is used for heat treatment. After the heat treatment the box is taken out of the furnace and can be cooled in air or be opened to remove the charge. The box can also be force-cooled on a cooling platform (page 20) while closed. Be sure that the protective gas flowrate is increased for this application.

  • Tmax 1100 °C
  • Protective gas box with process lid, vacuum lid, protective gas inlet and outlet through the furnace collar and seal profile for process lid with support for vacuum lid
  • Lid sealed with ceramic fiber, ceramic insulating materials can alternatively be used
  • Vacuum lid with rubber sealing gasket
  • Gas connection with quick-release coupling and 3/8 inch hose connection
  • Manipulating fork (up to N 17/HR)
  • Heat-resistant alloy 314 (AISI)/(DIN material no. 1.4841)
  • Charge thermocouple type K

Additional Equipment

  • Starting with model N 31/H, with a charging trolley
  • Digital temperature display
  • Vacuum pump
  • Protective gas system
Article no.FurnaceInner dimensions in mmExterior dimensions in mm*Preflush/cooling rateProcess flush rate
631000515N 7, N 7/H1041444215020010215 - 205 - 8
631000516N 7/H1641746221023011015 - 20 5 - 8
631000517N 11, N 11/R1642247221028013215 - 20 5 - 8
631000518N 11/H, N 11/HR1842747223033013215 - 205 - 8
631000519N 17, N 17/R1643747221043013215 - 20 5 - 8
631000520N 17/H, N 17/HR1844247223048013215 - 205 - 8
631000521N 31, N 31/H28427411233033017220 - 25 10 - 15
631000522N 21, N 41, N 41/H18427411223033017220 - 25 10 - 15
631000523N 41, N 41/H23432414228038020020 - 25 10 - 15
631000524N 4128437416233043022220 - 2510 - 15
631000525N 61, N 61/H26447416231053022220 - 2510 - 15
Larger boxes and custom dimensions available upon request *without vacuum lid
Thermal Process Technology I