Walking conveying furnaces

Disadvantages of walking beams relative to pushers are that walking beams have nearly twice as much skid-mark area and heat loss to water as pusher furnaces because of the walkers of the walking beams. However, these can be eliminated by a short soak zone at the discharge end of the furnace. (See reference 3.) 

Walking hearth reheat furnaces. These furnaces are mostly used for 

TABLE 4.1. Comparison of walking hearth heating curves with and without enhanced heating. (See figs. 6.26-6.29.) 

Low capacity in a reheat furnace was blamed on ineffective heat transfer in the charging ( convection ) zone, but that zone appeared to be hot. 

In several places the height of the bottom of the entry zone below crossover support beams for the skid rails was less than 1 ft (0.3 m), but the top zone height was 3 ft (0.9 m). (a) A major portion of the bottom gases migrated to the top zone, (b) The crossovers inhibited flow in the bottom zone. Both (a) and (b) reduced the possible convection heat transfer to the load in the bottom zone. 

---