Threaded pin · Doosan

Turning, groove, P2 thread and part-off · O1002 · CNMEC, small CNC workshop

The part

jaws part-off Z-2.54 Ø44 P2 thread · Ø25.255 groove
Machine
Doosan Puma lathe, Fanuc control
Program
O1002 · 244 lines · 4 operations
Stock
Ø50.8 (2") bar · inch model

Work cycle

  1. Profile rough + finish · T01
  2. Groove against the shoulder · T02
  3. Thread P2, 9 passes + spring pass G32 · T03
  4. Part-off at Z-44.64 · T02

About 3.7 min of cutting per part.

T0101 · T0202 · T0303

Last two digits = offset: the same number as the station.

Like the flange: T0202, T0101.

Geometry and wear of every insert from its own offset.

Full-depth thread

P2 external depth: 0.6134 × 2 = 1.227

Ø25.255 → Ø22.802

The thread gauge goes on. Groove at Ø22.4, below the root.

The 10 passes

nØdepth
124.4370.409
224.0990.578
323.8390.708
423.6200.818
523.4270.914
623.2521.002
723.0921.082
822.9421.157
922.8021.227
1022.8021.227

Depth ∝ √n → same chip section on every pass. The 10th is the spring pass.

Production details

  • Thread starts at Z8.: 5 pitches to accelerate
  • Groove Ø22.4: 0.4 below the thread root
  • Profile stops at Z-49.14, just past the part-off
  • Groove and part-off approach in G0; part-off ends at 0.05
  • Program O1002 (the flange is O1001)

Threading rules

  1. G99: F = pitch
  2. G97: fixed rpm
  3. 3–5 pitches to accelerate
  4. Groove deeper than the thread

All four are followed here.

Inches everywhere

50.8
2" (bar)
2.54
0.1" (face, passes)
0.127
0.005"/rev
91 m/min
≈ 300 ft/min

Before Cycle Start

  • Offsets 01, 02, 03 measured
  • ≥ 50 mm out of the jaws
  • T02 blade width
  • P2 60° threading insert
  • Parts catcher / tray
  • Thread gauge on the first part

Doosan codes

as this post uses them
  • G350 part-off confirmation
  • M24/M25, M34, M90, M110/M111
  • T0101 = station 1, offset 1
G-CODEblock-by-block explanation

Open the program on the control screen, with the reason for every line.