开口式和半闭口式轧机,中辊的上瓦胎多采用工字形,因此,一般称为工字瓦胎。这种形式的瓦胎缺点是:在中型轧机开坯第一架当两条腿受力不均匀时,上腿容易变形或折断。过去采用焊接修复方法,变形的用气焊割断后焊接,重复断,重复焊,多次反复后扔掉,损耗很大。 Open-type and semi-closed-type mill, the roller in the upper tire more use of I-shaped, therefore, generally known as I-shaped tiles. The disadvantage of this type of tiles is that the upper leg is easily deformed or broken when the first frame of a medium-sized rolling mill billet is unevenly stressed. In the past the use of welding repair methods, the deformation welding with gas welding cut off, repeated off, repeat the welding, thrown away after repeated, loss.