This invention is a method for making punches for punching complicated hollow filament spinning capillaries in one step. An inverse first punch is machined and then used to punch complicated inner recesses in the end of punch stock for the ultimate second punch. The second punch is further finished by machining. In addition, the complete method requires punching a complete female die using the second punch and then punching capillaries in spinneret webs located between the aligned die and second punch.
Segmented spinning capillaries for post-coalescent spinning provide the capability to spin round cross-section filaments with round continuous voids along the length of the filaments by adding an inner arcuate slot at the base of each spoke of each slot segment.
A spinneret made from a hardened metal plate having one or more slot shaped capillaries exiting the face of the spinneret. The walls of the capillaries taper toward the face of the spinneret, and each capillary has a length to width ratio of greater than about 2.
A spinneret has a number of combined orifices having different nominal dimensions. Yarns spun from such spinnerets have less doff-to-doff average standard deviation of yarn bulk.
A method of manufacturing a friction plate including a plurality of frictional material segments which are punched into a predetermined shape, and a core plate onto which the plurality of frictional material segments are annularly bonded, comprising step of punching out the frictional material segment in such manner that an edge portion thereof along the predetermined shape is given a punching load earlier than the other portions thereof in the process of punching.
