It is divided into preheating zone, heating zone, heat preservation zone and natural cooling.

炉体分为预热区、加热区、保温区、缓冷区。

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Specially designed air knife can prevent the flux from entering the preheating zone causing fire and remove excessive flux.

特制风刀设计，防止松香进入预热区产生火灼以及将多余松香排掉。

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Temperature difference from top to bottom in preheating zone of tunnel kiln is the biggest obstacle for rapid firing, energy saving.

隧道窑预热带内上下温差过大是实现快速烧成、节能降耗的最大障碍。

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