Electro-Hydraulic Hole PunchersAnnular CuttersMagnetic Drills Contact Us

 

 

GS-21F-035CA

 

 



 

 

Lower Thrust

Thrust limitations are a concern on some machine tools with larger sizes of twist drills and spade drills. Rotabroach Cutters have much lower thrust requirements, and are seldom a factor when selecting equipment. An approximate thrust force value can be determined from the following equation:

T=.7 x WT x FPT x NT Kc

        Where:

- T = Approx. Thrust (lbs.)
- WT = wall thickness (.188, .218, .264)
- FPT = Feed per Tooth (.002 - .005 ipt)
- NT = Number of teeth (Divide by 2 for "Hougen-Edge" geometry)
- Kc = Machinability factor as related to tensile strength

 

Type of Material
Kc
Free machining and low carbon steel
239,200
Plain carbon steel
BHN 125-160

254,000
283,000

Soft alloy steel
BHN 170-210

297,000
312,300

Med. hard alloy steel
BHN 220-250

326,000
341,000

Tool steels hot & cold worked BHN 210-250
355,000
Hard alloy steel BHN 260-300
370,000
Stainless
370,000
Cast iron BHN 180 max.
167,000
Cast iron BHN 180-250
196,000
Cast iron BHN 250-300
255,000
Aluminum
106,000