The shrinkage of the knitted fabric is a consequence of the introduction angle of the fabric and of the mechanical compression between the drum (heated cylinder) and the pressure roll. Indeed, the fabric which is compressed between the felt and the heated cylinder shrinks. The process is as following: the steam is going inside the holes of the fabric which is under tension and when the knitted fabric goes through the felt, we have the compaction. That’s why the steam box should always be in good condition and the steam regulation should be right. A bad regulation of the steam, will not give a good compaction. On the other side, too much steam can damage the felt surface.