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The universal chamber furnace with a built-in quenching bath is predestinated for heat and chemical heat treatment. Oxidation-free quenching, carburizing, carbonitriding and bright annealing can be carried out in the furnace. The furnace includes a gas-tight casing, built-in quenching bath, heating chamber, transloading chamber (forechamber) and rapid cooling chamber. Due to the gas-tight casing and a flame curtain, the charge is constantly surrounded by a controlled atmosphere during the whole quenching process including the transloading into the quenching bath or rapid cooling chamber. That is why the treated workpieces are not oxidized. A lift carrying the charge has two platforms which allow treating several charges simultaneously and therefore increasing production rate of the furnace. Figure. Structure diagram of RCC 6.9.6/9,5 furnace Rapid cooling in the protective atmosphere is ensured by a powerful centrifugal fan mounted under the roof to generate directed flow blowing over the charge. The built-in quenching bath is equipped with units for heating and cooling of quenching media. During oil quenching, the charge on the lower platform is immersed in a directed laminar oil flow generated by an agitator and deflectors in the bath that makes a provision for the maximum homogeneity and quality of workpieces’ quenching. The heating chamber is lined with advanced high-performance lining materials. The inner hearth lining is made of lightweight refractory bricks and the outer layer is made of ceramic fiber mats ensuring additional thermal insulation. To protect them from mechanical abrasion, the hearth floor is tiled with stiffened carborundum plates. The hearth lining is made of Unifrax ceramic fiber modules. Removable Tubothal heaters allow for easy replacement. The heaters are arranged against sidewalls of the furnace to provide uniform two-side heating of the charge. Heaters involve tubes made of Kanthal APM alloy and in turn arranged in heat-resistant tubes protecting them against carburizing effect of the furnace atmosphere. The heat-resistant fan is mounted under the furnace roof to achieve a highly homogeneous temperature distribution and atmospheric composition. Workpieces are transported between the forechamber and working chamber by a special chain pusher-puller. It moves within an individual duct in the hearth. In the idle position, the pusher-puller is retracted to the back wall of the furnace. Figure. Heating system of CNZ furnace To produce a controlled atmosphere, the furnace includes a space-saving generator of the furnace atmosphere ensuring its endogas composition by using an Oxican-Gamma catalyst rather than special generators. The carbon potential of the furnace atmosphere is measured by an oxygen probe (l-probe) mounted in the gas bleeder and automatically controlled by changing the furnace atmosphere composition. Carburizing in this furnace well differs from peer processes as it uses the new catalyst and fully automated process control solutions (catalytic gas carburizing provides rapid saturation and perfect quality of the carburized case). Universal automated unit for chemical heat treatment The unit allows the fully automated observance of chemical heat treatment parameters and guards against human factor influence on the quality of treated workpieces. Processes: - Oxidation-free quenching
- Carburizing
- Carbonitriding
- Tempering
- Bright annealing
- Nitriding
Operative personnel include one manufacturing technician responsible for process conditions programming and one operator responsible for transloading of bottom plates with workpieces between chambers of the unit. Proposed solutions for nitriding and carburizing are superior to peers in production rate and universality. 
Figure. RCCAN 6.9.6/9,5 complex unit
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