Where melt spinning solutions cannot succeed, FET provides a viable alternative with pilot and small scale production FET-200 Wet Spinning Systems. These may be used for a variety of solvent and polymer combinations:

• Wet spinning for processing new functional textile materials
• Allows maximisation of polymer and hence fibre properties
• Optimisation of process conditions for transfer to large scale
• Small scale production for bespoke high value products
• Available for multifilament, monofilament and staple fibre formats

FET-200 Features and Benefits

• Single or multiple dope vessels of various sizes for batch / continuous operation
• Continuous homogenization of spin dope with temperature control
• Exchangeable precision spin pumps and height adjustable spin engine
• Horizontal, vertical spinning in the coagulation bath, with unique thread-up system
• Temperature control of coagulation and solvent recovery
• Highly efficient washing haul-off systems
• Numerous combinations of washing baths available
• Filament drying systems with hot air circulation
• Flexible configuration of draw line components with multiple drawing zones
• State of the art computerised control system with data acquisition

Dry-jet wet spinning method

This method, also known as gel spinning, is an alternative to wet spinning. Some fibres, when spun directing into the bath, may create micro-voids that negatively affect the fibre properties. The polymer is dissolved in a solvent to make the fibre solution, which is then extruded under heat and pressure into an air gap before it enters a coagulation bath. The produced fibre is then washed and dried before it is heat treated and drawn. This method is often required for high performance fibres with a liquid crystal structure

Vertical wet spinning method

In the past, wet spinning has always been conducted by submersing the spinneret into the solution and conducting the extrusion horizontally. However, at FET, we have recently developed a vertical spinning system. This line utilises the Venturi effect to allow for better exposure of coagulation media with the dope and easier threading up of the yarn. This is particularly useful when working with more challenging coagulation solutions such as concentrated sulphuric acid or highly basic solutions.