GENERAL TECHNICAL INFORMATION FLANK CLEARANCE AND EFFECTIVE INCLINATION ANGLE Inclination angle b of the cutting edges corresponds to a specific thread helix angle l and insures equal clearance angle on both sides of insert. Correct Incorrect aL = aR aL < aR a - Flank clearance angle  - Helix angle  - Effective inclination angle is achived by selecting the suitable anvil. INFEED METHODS FOR THREADING OPERATIONS Flank feed Radial infeed Alternating flank infeed Flank equal Flank diminishing D1/2 D1/2 D2/2 H - Depth of thread profile H/2 D3/2 D2/2 D - Depth of pass Dn/2 D3/2 U - Depth of finishing pass ØD/2 Dn/2 U/2 Dn+1/2 ØD/2 U/2 D1 D2 D3 Dn D1 D2 D3 Dn Dn+1 = = = > > > > 2 2 2 2 2 2 2 2 2 1263