| 摘要 |
1,096,093. Making spinnerets. E. I. DU PONT DE NEMOURS & CO. Jan. 13, 1966 [Jan. 13, 1965], No. 1665/66. Heading B3A. [Also in Division B5] Fabrication of orifice 10 in spinneret plate 12 adapted for melt spinning and shown in Figs. 1 to 4 is started by drilling entrance hole 18 to the desired depth in a blank of stainless steel or other suitable metal. There may be one or more orifices 10 in each spinneret plate 12. Normally, the drill does not have the proper tip angle to form the divergent section 34, which in that case is either formed with a punch or by removing a small amount of material with a shaped drill. Another drilling or punching step is used to form the second divergent section 32. The first divergent section 26 is formed by a further punching step using a shaped punch. The protuberance of deformed metal thereby formed on the discharge face 16 is removed by rubbing the spinneret plate on abrasive paper. The capillary or discharge section 20 of orifice 10 is formed with a shaped punch. The protuberance thereby formed on the discharge face 16 of the spinneret plate is removed by rubbing and any burrs thereby left at the discharge orifice are removed by alternately cleaning out the capillary section with the shaped punch used to form it and rubbing the face 16 a sufficient number of times. The face of the spinneret is then given a high polish. An alternative method for removing burrs from the discharge orifice 20 is to place the face 16 on a lapping wheel which has a " long nap " cloth. If a rounded edge is thereby formed between walls 23, 24 and discharge face 16, the essential sharp edge at this point is produced by a light final lapping step with a fine abrasive followed by a final polishing step. |
