Task setting:

One of ISW’s customers is a plant manufacturer who offers its customers from the textile industry a modern and much more time-saving inspection system for the control of
spinning plate capillaries than is currently available. Spinning plate capillaries are bores of only 0.35 millimetres in diameter which are located on the outer track of so-called nozzle plates. The 800 millimetre circular plates are used as tools in the production of textile basic materials. For this purpose, plastic polymers obtained from recycled PET bottles are pressed through the capillaries under very high pressure. In this way, up to 46,000 individual threads are produced, which are then interlaced to form a strand. In further processing, these strands are refined in various process steps into a cotton-like substitute textile, which forms the basis of many high-tech textiles.


Specializing in user-specific solutions for non-contact quality inspection, ISW developed an inspection microscope that inspects the nozzle plate capillaries 288 times faster than previous solutions during yarn production for textile production.

More than 550,000 capillary exams per month

Up to 12 nozzle plates are located in one system, with each plate having more than 46,000 spinning plate capillaries. In order to guarantee the quality of the strand density, these must be checked every month and cleaned individually as required. Previously, this inspection was performed manually by qualified personnel inspecting each individual bore hole with a nozzle microscope via a linear unit. The complete testing process of a plate with the corresponding cleaning steps of clogged capillaries took up to 3 days. The client wanted an inspection system that was capable of eliminating this large amount of time, and specified a maximum inspection time of one hour per nozzle plate. The developed, automated image processing system needs only 15 to 20 minutes. In the ISW application, an image-supported 100 percent inspection is carried out using a Gigabit Ethernet camera, a telecentric lens and appropriate background lighting. During the automatic rotation of the nozzle plate on the inspection set-up, the digital camera takes 120 pictures per inspection process. The backlighting then shows the specialist staff which capillaries are clogged and need cleaning.

Customer benefits:

The very large number of inspection processes results in massive time savings and significantly lower error rates. The system runs to the full satisfaction of the company using it.