KHK Gears - Steel Ring Gears (SIR)

Unit of Measure

Items	SIR2.5-120 KHK SIR2.5-120, Module 2.5, 120 Tooth, Internal Ring Gears	SIR2.5-200 KHK SIR2.5-200, Module 2.5, 200 Tooth, Internal Ring Gears	SIR2-120 KHK SIR2-120, Module 2, 120 Tooth, Internal Ring Gears	SIR2-200 KHK SIR2-200, Module 2, 200 Tooth, Internal Ring Gears	SIR3-120 KHK SIR3-120, Module 3, 120 Tooth, Internal Ring Gears
Gear Type	N/A Internal Gears
Construction	N/A Internal Ring Gears
Module	N/A 2.5	N/A 2.5	N/A 2	N/A 2	N/A 3
No. of teeth	N/A 120	N/A 200	N/A 120	N/A 200	N/A 120
Shape	N/A T1
Bending Strength	N/A 807 N·m82.3 kgf·m	N/A 1320 N·m135 kgf·m	N/A 413 N·m42.1 kgf·m	N/A 677 N·m69 kgf·m	N/A 1390 N·m142 kgf·m
Surface Durability	N/A 138 N·m14 kgf·m	N/A 220 N·m22.5 kgf·m	N/A 68.8 N·m7.02 kgf·m	N/A 110 N·m11.2 kgf·m	N/A 244 N·m24.9 kgf·m
Backlash	N/A 0.0075-0.0161 in0.19-0.41 mm	N/A 0.0087-0.0181 in0.22-0.46 mm	N/A 0.0067-0.0146 in0.17-0.37 mm	N/A 0.0079-0.0161 in0.20-0.41 mm	N/A 0.0087-0.0177 in0.22-0.45 mm
Precision Grade	N/A JIS grade N9 (JIS B1702-1:1998)
Gear Teeth Type	N/A Standard Full Depth
Pressure Angle	N/A 20 º
Material	N/A S45C (AISI 1045) Carbon Steel
Tooth Hardness	N/A (less than 194HB)
Surface Treatment	N/A Black oxide coating
Weight	N/A 5.55 kg12.236 lb	N/A 8.94 kg19.709 lb	N/A 2.98 kg6.570 lb	N/A 4.8 kg10.582 lb	N/A 9.28 kg20.459 lb
Internal Diameter (A)	N/A 11.614 in295 mm	N/A 19.488 in495 mm	N/A 9.291 in236 mm	N/A 15.591 in396 mm	N/A 13.937 in354 mm
Pitch Diameter (C)	N/A 11.811 in300 mm	N/A 19.685 in500 mm	N/A 9.449 in240 mm	N/A 15.748 in400 mm	N/A 14.173 in360 mm
Outer Diameter (D)	N/A 13.976 in355 mm	N/A 21.850 in555 mm	N/A 11.260 in286 mm	N/A 17.559 in446 mm	N/A 16.693 in424 mm
Face Width (E)	N/A 0.984 in25 mm	N/A 0.984 in25 mm	N/A 0.787 in20 mm	N/A 0.787 in20 mm	N/A 1.181 in30 mm