Thermal Process Technology

Protective Gas Annealing Bag and Holder for Models N 7 - N 61/H

Protective gas annealing bag in operation

Holder with protective gas annealing bag

Thermocouple integrated in holder

Working with the Protective Gas Annealing Bag and Holder

When workpieces made of air-hardened steel must be heat treated under protective gas and quenched, the protective gas annealing bag with holder is an optimal solution. This system consists of a holder with charge carrier and protective gas tube as well as a bag made of stainless steel heat treating foil. We would be pleased to carry out trials at our technical center. The charge is placed on the charge carrier and covered with the protective gas annealing bag. The bag is preflushd with protective gases such as argon, nitrogen or forming gas 95/5 (page 15) and placed together with the holder in the furnace. After the charge has been heated, the protective gas annealing bag and holder are removed from the furnace and cooled with the help of the forced cooling system (page 17) or in still air. At the same time the workpiece remains in the bag in the protective gas atmosphere. This prevents oxidation from occuring. Due to thin-walled foil very rapid cooling times can be achieved. The protective gas annealing bag is also suitable for quenching workpieces in oil or water. The protective gas annealing bag with holder is taken out of the hot furnace after the heating time. The bag is pulled off the holder above the quenching bath using a heat protection glove (page 22). After this the workpiece can slide directly into the quenching bath. In most steels, the brief exposure to ambient air while being pulled out normally has no effect on surface oxidation of workpieces. The bags can be used multiple times. Our experience shows that at temperatures < 950 °C the stainless steel heat treating bag lasts for approx. 10-15 processes. At temperatures between 950 °C and 1050 °C, use for approx. 5 - 10 processes can be assumed.

  • Tmax 1200 °C
  • Holder with protective gas annealing bag, protective protective gas through notch in upper furnace collar
  • Supplied with three protective gas annealing bags
  • Gas connection with quick-release coupling and 3/8 inch hose connection
  • Holder with hand handle
  • Heat-resistant alloy 314 (AISI)/(DIN material no. 1.4841)
  • Charge thermocouple type K
  • Digital temperature display (page 16) and protective gas systems (page 15) optional
  • Charging trolley optional
Article no.FurnaceInner dimensions in mmMax. workpieceReplacement hoodPreflush/cooling rateProcess flush rate
  wdhlength in mm(article no.)l/minl/min
631000539N 7.. - N 61..802504018049104082515 - 205 - 8
631000540N 7.. - N 61..1202506018049104222515 - 205 - 8
631000541N 11.. - N 61..1203506028049104223515 - 205 - 8
631000542N 11.. - N 61..1603508028049104363515 - 205 - 8
631000543N 17.. - N 61..1604208035049104364015 - 205 - 8
631000544N 41.. - N 61..20042010035049104524220 - 2510 - 15