Formerly Emhart Teknologies & Infastech

Thread Turning - Carbide Inserts

Thread Turning - Carbide Inserts

Thread turning is another option for making internal threads when tapping conditionals are not optimal, such as parts with large diameters or in difficult to cut materials. Thread turning is most often performed on a lathe with a cylindrical workpiece, and uses an indexable carbide insert with a boring bar. When boring bars are too large for the size of hole, a solid carbide threading bar can be used. In thread turning, the workpiece rotates as the cutting tool moves axially to create a continuous thread path. Like thread milling, it normally takes multiple passes to generate a full thread profile. Unlike a thread milling cutter, all the material removal is accomplished with only one cutting edge engaged. Removing only a fraction of the thread depth in each pass keeps the cutting edge from being overloaded.

Insert Selection Process:

  1. Determine thread size and minimum minor diameter
  2. Determine minimum bore size smaller than the minor diameter from the chart below
  3. Select appropriate insert blank size for minimum bore
  4. Select Spiralock part number for corresponding insert blank and pitch size using chart on the following page

 

Min. Bore Insert Size Pitch Range Boring Bar (example)
0.240 06 20-32 TPI (1.00-0.45 mm) SIR 0205 H06
0.310 08 16-32 TPI (1.50-0.45 mm) SIR 0265 K08
0.350 08 SIR 0310 K08
0.470 11 14-32 TPI (1.75-0.45 mm) SIR 0375 H11
0.470 11 SIR 0375 K11
0.470 11 SIR 0375 M11 C
0.580 11 SIR 0500 L11
0.580 11 SIR 0500 P11 C
0.640 16 7-32 TPI (3.50-0.45 mm) SIR 0500 M16
0.750 16 SIR 0625 P16
0.750 16 SIR 0625 R16 C
0.900 16 SIR 0750 P16
1.160 16 SIR 1000 R16
1.400 16 SIR 1250 S16
1.650 16 SIR 1500 T16
0.900 22 6 TPI (5.00-0.45 mm) SIR 0750 P22
1.160 22 SIR 1000 R22
1.500 22 SIR 1250 S22

 

Thread Turning - Carbide Inserts

 

Ordering Code: SPL part number + Modifiers
    No suffix for Right Hand threads or BT thread direction
Add ‘LH’ for Left Hand threads
Add ‘TT’ when cutting from opposite end of a through hole

 

Example: SPL90154LH is an 18 pitch insert for cutting left hand Spiralock threads, and is made from an ISO size 16 blank

 

Part Number Pitch ISO Blank Size/ Inscribed Circle
SPL90324 32 06 (5/32”)
SPL90326 28
SPL90328 24
SPL90330 20
SPL90332 18
SPL90334 32 08 (3/16”)
SPL90336 28
SPL90338 24
SPL90340 20
SPL90342 18
SPL90344 16
SPL90114 32 11 (1/4”)
SPL90116 28
SPL90118 27
SPL90120 24
SPL90122 20
SPL90124 18
SPL90126 16
SPL90128 14
SPL90144 32 16 (3/8”)
SPL90146 28
SPL90148 27
SPL90150 24
SPL90152 20
SPL90154 18
SPL90156 16
SPL90158 14
SPL90160 13
SPL90162 12
SPL90164 11.5
SPL90166 11
SPL90168 10
SPL90170 9
SPL90172 8
SPL90174 7 22 (1/2”)
SPL90176 6
SPL90300 0.50 06 (5/32”)
SPL90302 0.75
SPL90304 1.00
SPL90308 0.50 08 (3/16”)
SPL90310 0.75
SPL90312 1.00
SPL90314 1.25
SPL90316 1.50
SPL90014 0.80 11 (1/4”)
SPL90016 1.00
SPL90018 1.25
SPL90020 1.50
SPL90022 1.75
SPL90038 0.80 16 (3/8”)
SPL90040 1.00
SPL90042 1.25
SPL90044 1.50
SPL90046 1.75
SPL90048 2.00
SPL90050 2.50
SPL90052 3.00
SPL90054 3.50 22 (1/2”)
SPL90056 4.00
SPL90058 4.50
SPL90060 5.00
SPL90062 5.50 27 (5/8”)
SPL90064 6.00

 

Thread Turning - Carbide Inserts