5/16" x 18 UNC Bottoming Chrome Tap

UNC | UNIFIED NATIONAL COARSE BOTTOMING

About this item:

• 5/16" x 18 UNC Bottoming Chrome Tap
  
• Chrome Alloy UNC Bottoming Hand Tap.
• Used as thread chasers to clean an existing thread.
• They can also be used to create a new female thread in non-ferrous metals and plastics.
• Chrome alloy taps are not suitable for creating precision, safety or critical threads.
• Unified National Coarse thread form was introduced in 1948 as an attempt to standardise thread forms in the USA, Canada and the UK.
• The thread profile of UNC is the same as for metric threads and is described in the JIS B0206 standard.
• The thread is described by its major diameter and the number of threads per inch of length (TPI).
• This thread series is commonly used in the mass production of bolts, screws and nuts.
• It is used for threading into lower tensile strength materials (bronze, brass, aluminium and plastics) to obtain the best resistance to stripping of the internal thread.
• It is also used on quick assembly or disassembly or if corrosion or slight damage is possible.
• Bottoming Taps have a lead of two threads and are used to ensure minimum thread run-out when tapping to the bottom of a blind hole.
• Bottoming Taps are typically preceded by the use of a Taper or Intermediate Tap.