TMPG_US-EN

Speeds and Feeds | Metric

Hardness (BHN) 100 - 150 150 - 200 200 - 250 125 - 175 175 - 225 225 - 275 125 - 175 175 - 225 225 - 275 275 - 325 125 - 175 175 - 225 225 - 275

Speed (M/min)

Material

ISO

Machinability* Easy

Free Machining Steel 1118, 1215, 12L14, etc.

221 168 137 221 168 137 122 137 122 107 137 122 107 91 91 76 91 76 107 137 122

Easy Easy

Low Carbon Steel 1010, 1020, 1025,

85 - 125 Average

Average Average Average Average Average Average Average Average Average Average

1522, 1144

Medium Carbon Steel 1010, 1040, 1050,

1527, 1140

P

Alloy Steel

4140, 5140, 8640

275 - 325 Difficult 325 - 375 Difficult 225 - 300 Average

High Strength Alloy 4340, 4330V, 300M

300 - 350 350 - 400

Difficult Difficult

Structural Steel A36, A285, A516

100 - 150 Average 150 - 250 Average

250 - 350 91 NOTE: Feed rates provided are safe starting recommendations and may be increased to reduce cycle times. Solid carbide thread mills may perform at double or triple these feed recommendations. Difficult

38 | THREAD MILLING REFERENCE GUIDE