3893322

Information

• Patent Grant
• 3893322

• References
• Source

• Patent Number

  3,893,322

• Date Filed

  Not available

• Date Issued

  Tuesday, July 8, 1975
  50 years ago

• CPC

  • B21H3/12 - articles with helicoidal surface
  • B21C37/20 - Making helical or similar guides in or on tubes without removing material
  • B21C37/207 - with helical guides
  • B21H7/14 - knurled articles
  • F28F1/12 - the means being only outside the tubular element

• US Classifications

  • 072 - Metal deforming
  • 165 - Heat exchange