It was found that in using Winch machines, there were some inherent problems. So the Jet dyeing machines when they came up in the 1970's, were specifically designed to overcome those shortcomings.
In the Jet dyeing machine the reel is completely eliminated. A closed
tubular system exists where the fabric is placed. For transporting the
fabric through the tube a jet of dye liquor is supplied through a
venturi. The Jet creates turbulence. This helps in dye penetration along
with preventing the fabric from touching the walls of the tube. As the
fabric is often exposed to comparatively higher concentrations of liquor
within the transport tube, so little dye bath is needed in the bottom of
the vessel. This is just enough for the smooth movement from rear to
front. Aqueous jet dyeing machines generally employs a driven winch reel
along with a jet nozzle.
The following diagram explains the functioning of a Jet dyeing machine: