Our protective gas and carburization modules allow you to upgrade our annealing and hardening furnaces into a compact annealing and hardening system as an economical alternative to expensive vacuum systems and protective gas furnaces. We can recommend different systems based on your application. Our professional test center will be pleased to test your product samples in order to specify the right heat treatment equipment for you.

Annealing Box
Our annealing boxes with lid sealing may be used for carburizing, annealing and hardening in neutral atmospheres, powder nitriding or boriding. Your charge is placed in the box and bedded in carburizing granulate, neutral annealing coal or nitriding or boriding powder. The box is sealed, and when heated, the resulting atmosphere in the closed annealing box provides for the respective surface reaction of the charge. For carburizing and similar processes, the annealing box may be removed while hot, opened and the charge quenched in fluid. For annealing processes, the box may remain in the furnace until it is cooled down.

Annealing Tray with Alloy Bag
This system, consisting of a lightweight tray with gas port and alloy bag, is particularly useful for air-quenched steels. The thin-walled alloy bag allows fast heat transfer. Its protective gas connections allow you to process your charge in a defined atmosphere. The small size of the gas lightweight tray you to pre-flush or cool the unit outside the furnace or place it on a cooling table for fast cooling by fan.

Annealing Box with Protective Gas Inlet and Outlet
The boxes are equipped with lid and protective gas inlet and outlet. The lid is sealed by means of a sealing channel with a high-temperature rope gasket before it is introduced into the furnace. The furnace is equipped with a special passage for the protective gas connections. The box is connected to a gas supply panel to introduce the required atmosphere in the box. When the heating process is finished, the box may be removed from the furnace, the lid removed and the parts quenched in liquid or air.

Annealing Box with Protective Gas Inlet and Outlet constructed for Evacuation Ambient Temperatures
This version of our annealing box is designed to be evacuated prior to the heating cycle. After evacuation, the box is refilled with a protective atmosphere for the heating cycle. This system is particularly useful for bright annealing of bulk materials, and nonferrous and noble metals, since oxygen can be more efficiently removed from the box by evacuation than through purging. Temperature-resistant seals allow this version of the annealing box to maintain a vacuum at ambient temperatures.

Additional Accessories
In addition to the above-mentioned protective gas and carburization systems, Nabertherm has a variety of heat treatment accessories ranging from the sealing cords for the annealing boxes to fully automatic gas supply panels.

Powder nitriding in an annealing box

Powder carburizing of steel

Protective gas box used in a large bogie hearth furnace with air circulation

Custom-sized box for fork-lift loading

Annealing tray with alloy bag

Bulk material bright annealing in an annealing box with evacuation facility