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REAMING TITANIUM Initial Cutting Data In Reaming
Reaming Allowance
When reaming titanium, guide values for the reaming allowance – a material
stock (per diameter) left for reaming – are shown in Table 44.
Table 44 Diametral Reaming Allowance for BAYO T-REAM Tools
From 16 to 32
From 13.5 to 16
From 11.5 to 13.5
(from 0.5315 to 0.63)
(from 0.4528 to 05315)
0.20-0.35
0.20-0.30
0.15-0.25 Allowance for hole diameter (from 0.63 to 1.26)
(0.006-0.01) (0.008-0.012) (0.008-0.014)
* units: mm (in)
Cutting Speed
Initial cutting speed Vc is calculated by equation (11):
Vc=Vo×Km (11)
Where: Vo=45 m/min (148 sfm) – basic cutting speed
Km – machinability factor (Table 9)
Feed
Table 43 provides data for setting starting feed per tooth fz.
Table 43 Recommended Feed Values for BAYO T-REAM Tools*
Feed fz, mm/tooth (IPT)
Through hole Blind hole
Connection
Size Smooth Interrupted Smooth Interrupted
0.04-0.05-0.07 0.03-0.04-0.06 0.03-0.04-0.06 0.03-0.03-0.05
BN5…BN6
(0.0016-0.002-0.0027) (0.0012-0.0016-0.0024) (0.0012-0.0016-0.0024) (0.0012-0.0012-0.002)
0.05-0.07-0.09 0.04-0.06-0.08 0.04-0.06-0.07 0.04-0.05-0.06
BN7…BN9
(0.002-0.0027-0.0035) (0.0016-0.0024-0.0031) (0.0016-0.0024-0.0027) (0.0016-0.002-0.0024)
* recommended feed values are given as: minimal-starting-maximal
When reaming with BAYO T-REAM tools, the best results are reached with coolant pressure
15-20 bars (217-290 psi).
Example
Find cutting data for reaming a through hole in the process of manufacturing a titanium part. The
titanium grade is Ti-10V-2Fe-3Al, the required hole diameter is specified as Ø25Js8. It is planned
to apply a BAYO T-REAM reamer carrying a specially designed 8-flute head with BN8 connection.
Machinability factor Km=0.56 (Table 9).
According to equation (11), initial cutting speed Vc will be as follows:
Vc=45×0.56=25 (m/min) or 83 sfm.
Spindle speed n=( 1000×25) ⁄ (π×25)=318 (rpm)
From Table 44 starting feed fz=0.07 mm/tooth (0.0027 IPT).
Feed speed Vf=0.07×8×318=178 (mm/min) or 7 IPM.
56 ISCAR