Tech Tip #114: Available SAE Housing Sizes, Available Clutch Sizes, Torque Capacities & Key Dimensions

Dr. Diesel
Written by Dr. Diesel

Helpful guide for Twin Disc/Rockford PTOs: Available SAE Housing Sizes, Available Clutch Sizes, Torque Capacities & Key Dimensions

Need help sizing a Twin Disc®/Rockford power takeoff? Do you find Twin Disc PTO Model Numbers confusing? The chart below will help you. The first column “PTO Model Number” lists the available Twin Disc power takeoffs by the number of clutch plates and clutch size. In other words, Twin Disc PTO part numbers are based on the physical size of the PTO and its internal components.

Specifications Application Duty Classification
Class 1 Clutch Maximum HP Rating
see note 2
PTO Model
Number
Available. Sizes
SAE
Max. Input Torque
Lb. Ft.
Class II Class III Class IV Approx. Weight
in LBS.
C-106SP
C-107SP
C-108SP
C-110SP
C-111SP
6,5,4
6,5,4
5,4,3
4,3,2,1
4,3,2,1
159
175
230
328
387
40
54
61
96
124
27
36
41
64
82
20
27
31
48
62
53
65
72
115
120
SP-11P
SP-111HP
SP-111OP
3,2,1
3,2,1
3,2
455 124 82 62 129
141
145
 SP-211HP
SP-211OP
3,2,1
2,1
909 247 165 124 155
175
SP-311P 2,3 1620 371 247 186 220
SP-114P 1,0 810 188 125 94 260
SP-214P
SP214OP
1,0 1620 376 251 188 328
340
IBF-240OP
IBF-214OP
1,0 1620 395 264 197 470
SP-314HP
SP-314HP
1,0 2430 564 376 282 408
IBF-314OP
IBF-314OP
IBF-314OP
1,0 3040 7413 494 3713 595
SP-218OP
SP-218OP
0,00 4000 622 415 311 660
SP-318P 0 6000 933 622 467 700
IBF-318OP

IBF-318OP

IBF-318OP

0 7500 12243 8163 6123 920
SP-321P
IBF-321OP
0,0
0,0
6730
8400
1270
16673
847
11113
 635
8343
1110
121

The first digit in the alphanumerical Twin Disc model number is the number of clutch plates. The next digit of the Twin Disc model number is the clutch size in inches. Putting this together, a Twin Disc Model C106SP is a single plate, 6″ clutch. The next column lists the available power takeoffs by SAE bell housing sizes. To continue our example, a Twin Disc Model C106HP5 has an SAE #5 housing. If you are rusty on SAE housing dimensions, take a look at our Tech Tip #41, SAE Bell Housings Made Easy!. The next column lists the maximum torque capacity that a particular clutch size will handle. The next two columns refer to SAE duty classifications for PTOs, and the last column gives the weight.

Manufacturers names, symbols and numbers are for reference purposes only and do not imply manufacturing origin.

Dr. Diesel
Written by Dr. Diesel
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