Cooling Crimping

Texturing. The final step in olefin fiber production is texturing the method depends primarily on the appHcation. For carpet and upholstery, the fiber is usually bulked, a procedure in which fiber is deformed by hot air or steam jet turbulence in a no22le and deposited on a moving screen to cool. The fiber takes on a three-dimensional crimp that aids in developing bulk and coverage in the final fabric. Stuffer box crimping, a process in which heated tow is overfed into a restricted oudet box, imparts a two-dimensional sawtooth crimp commonly found in olefin staple used in carded nonwovens and upholstery yams. 

Figure 12.11 Schematic of a modern staple drawline for PET fibers 1, spun yarn supply cans 2, lubricating bath 3, two-stage drawing 4, heatsetting 5, cooling 6, reheating 7, crimping 8, dyeing 9, cutting 10, baling...

After cooling the vials to room temperature, add 2 ml hexane, close the vial again and vortex for 10 s. Transfer the upper (hexane) layer to a glass tube with a cone bottom and carefully evaporate the hexane with a gentle stream of nitrogen at room temperature. Finally, dissolve the residue in 100 pi (plasma) or 80 pi (erythrocytes) of hexane and transfer the sample to a GC injection vial with a crimp cap or a screw cap. Inject 1 pi into the GC. 

Transfer the sample after cooling down into a crimp-cap vial and close the vial with a cap and insert (Alltech). This sample is ready for GC-MS analysis. 

Great efforts have been made in recent years in order to validate the different instruments not only in comparing principle and results but also in determining the critical parameters such as heating and cooling rates, particle size, weight, resolution, atmosphere, and type of pans (crimped pan, sealed pan, open pan, etc.). 

Figure 1-26. Flowchart showing steps in the manufacture of nylon 6, 6. facture of nylon 6,6. Specific amounts of the two chemicals are combined in solution to form nylon salt. The salt is purified, polymerised, extruded in ribbon form and chipped into small flakes or pellets. The polymer is then melted and extruded through a spinnerette into cool air, where the filaments are formed. The filaments are then stretched or cold drawn to develop desired properties. Nylon staple is obtained by crimping filament tow and then cutting into short uniform lengths.

The ointment is then filled in presterilized eye ointment tubes, which are crimped and allowed to cool to room temperature. 

Summer fur begins to grow rapidly in the spring, producing long and coarse hairs that are less crimped to inhibit the formation of air pockets and to permit cooling. 

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