Tapping PDF

Tapping Screw threads can be divided into two basic categories, those which provide a fastening (as in nuts and bolts) and those which transmit motion. Screw thread terms GMI PRODUCTION TECHNOLOGY  V threads The most commonly used thread is the V- thread, w...

Tapping Screw threads can be divided into two basic categories, those which provide a fastening (as in nuts and bolts) and those which transmit motion. Screw thread terms GMI PRODUCTION TECHNOLOGY  V threads The most commonly used thread is the V- thread, which is used for all types of bolts, nuts and screws. The included angle between the flanks of the thread is 60° and this combined with a suitable pitch provides a very good self-locking action. GMI PRODUCTION TECHNOLOGY  Tapping Tapping is the cutting of thread grooves in the workpiece using a multi cutting-edged tool with a particular cutting edge shape. The tool is rotated by hand about its longitudinal axis. GMI PRODUCTION TECHNOLOGY  1 2 3 1 2 3 No 1 (taper) = 1 ring on shank No 2 (plug) = 2 ring on shank No 3 (bottoming) = without ring GMI PRODUCTION TECHNOLOGY  Wrench Tap Tool GMI PRODUCTION TECHNOLOGY  1 2 3 4 5 Step 1 : Drilling Step 5 : Bottoming Step 2 : Countersinking Step 3 : Taper Step 4 : Plug GMI PRODUCTION TECHNOLOGY  Work Technique B (A) Main motion = rotary motion of the tap A (B) Feed motion = axial motion in the workpiece Checking the squareness of the tap to the workpiece GMI PRODUCTION TECHNOLOGY  Cutting Fluids A proper cutting fluid must be applied during the cutting operation. Cutting fluids provide: 1) smoother 2) improved surface finishes 3) increased tap life 4) chip removal 5) decrease tap breakage 6) improved thread quality GMI PRODUCTION TECHNOLOGY