燃料气的流动速度   燃料气的流动速度与火焰的长短有密切关系，在外混式燃烧器中，燃料气流速过大，会引起脱火；在半预混燃烧器中，燃料气流速过小会引起回火。

There is a close relatihip between the flow velocity and flow velocity of flame fuel gas fuel gas in the length of the outer mixing burner, fuel gas flow rate is too large, will cause the removal of fire; in the semi premixed burner, fuel gas flow rate is too small will cause tempering.

用于加热小断面料坯的炉子只有预热段和加热段。

习惯上还按炉内安装烧嘴的供热带划分炉段，依供热带的数目把炉子称为一段式、二段式，以至五段式、六段式等。50～60年代，由于轧机能力加大，而推钢式炉的长度受到推钢长度的限制不能太长。

The furnace used for heating small broken fabric billet is only preheating section and heating section.

It is customary to divide the furnace section according to the heating belt with the burner in the furnace. According to the number of tropics, the furnace is called the one section, the two section, and the five section and the six section. In the 50~60 era, due to the increase of rolling mill capacity, the length of pusher furnace must not be too long due to the length of steel pushing.