These are the most popular hank dyeing machines, these machines are designed to have liquor flow parallel to the yarn and they work with low liquor ratios to save substantially in consumption of thermal energy ,water and chemicals.The material to be dyed in hanks is loaded on the sticks ,generally two sticks are used one at the top and other at the bottom. The bottom stick is used to avoid the yarn entanglement during the liquor flow. The carriers are loaded with the sticks having hanks ,the sticks are supported into slots made in the body of the carrier.
The loaded carriers are then put into the dyeing machine and door is closed. In a second variant of the machine , the machine is open at the top and career is loaded from the top , which ,a rubber gasket is provided around the periphery on which the machine career rest, and vessel is sealed by the weight of the career and material, thus making closed circuit. The liquor circulation and flow remains the same as in ordinary cabinet machine.
The dye liquor in these machines moves while the material remains stationary. The flow direction is reversed frequently to ensure level dyeing.
A cabinet dyeing machine consists of following main components,
1.Main dyeing vessel made of SS
2.Carriers for loading of hanks with SS sticks for loading of hanks.
3.An internal axial pump or an external pump for liquor circulation.
4.An indirect heating system(with internal or external heat exchanger)
5.An addition tank with injector pump
7.An internal or external sampling device
Main features of the cabinet dyeing machines are,
1.These machines are most researched ,developed and technically advanced ,and these are most preferred choice for the dyeing of all types yarn in hank form.
2.Modern machines are more flexible and capable of partial or half loading ,without changing the M:L, by using either dummies or by using special loaders , which can be easily adjusted in the machines. The new machines are equipped with continuous variable volume control and monitoring system ,which maintains the M:L even at reduced load .
3.Machine capacities available with same material to liquor ratios ,from lab scale to 1000 kgs for bigger lot size. Coupling of similar capacity machines is also possible to get even bigger lots.
4.All features such as inverter controlled pumps ,dosing and automatic color kitchen and fully automatic dyeing controllers ,same as package dyeing machines are available in these machines.
5.These machines are suitable for dyeing of various sizes of hanks ( from 48” to 90 “) in different qualities such as cotton, viscose, cotton blends, acrylic, wool and its blends and nylon etc. without any problem.
6.The liquor ratio of machines varies between 1:10 to 1:15, depending upon the machine and quality of material to be processed.
7.In the machines with air pad technology , the air pad acts as a air cushion to take care of expanded dye liquor and it is possible to work with higher pressure and temperture The machines with air pad are capable of working up to a maximum temperature of 135 0 C and there is no need of an extra heat exchanger to cool down the expanded dye liquor. Since the machine works in a closed circuit mode ,therefore the entire dye liquor participate in the dyeing.
8. The machines may be having a preparation tank with a quick transfer pump for faster liquor transfer from and to the machine without losing time and reducing the overall dyeing cycle. New machines are equipped with automatic color kitchen , multiple feeding and drainage points for more efficient and cleaner working.
9.The machines are equipped with an internal or external sampling device ,which allows the inspection of samples at any point of dyeing cycle ,without disrupting the actual dyeing process.
10. The machines with interchangeable extra careers offer mach more flexibility in terms of saving in loading /unloading time as well as automation of loading and unloading.