The invention discloses a reduction furnace chassis having 48 pairs of bars. The reduction furnace chassis comprises a chassis main body and electrodes. The electrodes have 48 pairs and are divided into four ring-shaped structures on the chassis so that four electrode rings are formed on the chassis. The four electrode rings comprise an electrode ring 1, an electrode ring 2, an electrode ring 3 and an electrode ring 4 orderly arranged from inside to outside. Each one of two sides of each one of the electrode rings is provided with a gas outlet loop formed from a plurality of gas outlets and an air inlet ring formed from a plurality of air inlets. The air inlet ring comprises three rings, one ring is arranged on the inner side of the electrode ring 1 and one ring is arranged on the outer side of the electrode ring 4. The chassis can promote silicon rod surface material gas cycling so that high quality polycrystalline silicon rods are obtained. The chassis realizes cooling in the inner wall of an immersion bell, reduces immersion bell inner wall cleaning frequency, reduces a heat radiation loss in the furnace, improves production efficiency, improves a material conversion rate and reduces production energy consumption.