Modified Stock Gearing - Boston Gear

Helical Gears
Approximate Horsepower and Torque* Ratings
For Class I Service (Service Factor = 1.0)
No. 25 RPM 50 RPM 100 RPM 200 RPM 300 RPM 600 RPM 900 RPM 1200 RPM 1800 RPM 3600 RPM
Teeth H.P. Torque H.P. Torque H.P. Torque H.P. Torque H.P. Torque H.P. Torque H.P. Torque H.P. Torque H.P. Torque H.P. Torque
24 DIAMETRAL PITCH – 33.94 NORMAL DIAMETRAL PITCH HARDENED STEEL .250-.375" FACE
8 .01 13.5 .01 13.5 .02 13.4 .04 13.2 .06 13.0 .12 12.5 .17 12.0 .22 11.6 .31 10.8 .51 8.9
10 .01 18.0 .01 17.9 .03 17.8 .06 17.4 .08 17.1 .16 16.3 .22 15.5 .28 14.8 .39 13.6 .62 10.9
12 .01 22.5 .02 22.3 .04 22.1 .07 21.6 .10 21.1 .19 20.0 .27 18.9 .34 17.9 .46 16.2 .72 12.6
15 .01 29.1 .02 28.9 .05 28.5 .09 27.8 .13 27.1 .24 25.2 .34 23.5 .42 22.0 .56 19.6 .84 14.8
18 .01 23.6 .02 23.4 .04 23.1 .07 22.4 .10 21.7 .19 19.9 .26 18.4 .33 17.1 .43 15.0 .62 10.9
20 .01 26.8 .02 26.5 .04 26.1 .08 25.2 .12 24.3 .21 22.2 .29 20.4 .36 18.8 .47 16.3 .67 11.7
24 .01 32.6 .03 32.3 .05 31.6 .10 30.3 .14 29.2 .25 26.1 .34 23.7 .41 21.6 .53 18.5 .73 12.8
30 .02 41.3 .03 40.8 .06 39.7 .12 37.8 .17 36.0 .30 31.6 .40 28.1 .48 25.3 .60 21.1 .81 14.1
36 .02 49.9 .04 49.1 .08 47.6 .14 44.9 .20 42.4 .35 36.4 .46 31.9 .54 28.4 .66 23.3 .86 15.1
48 .03 67.0 .05 65.6 .10 63.0 .19 58.3 .26 54.3 .43 45.0 .55 38.4 .64 33.5 .76 26.6 .94 16.5
60 .03 83.8 .06 81.6 .12 77.6 .22 70.7 .31 64.9 .50 52.0 .62 43.4 .71 37.3 .83 29.0 1.00 17.5
72 .04 101 .08 97.7 .15 92.1 .26 82.5 .36 74.8 .56 58.3 .68 47.8 .77 40.5 .89 31.0 1.00 18.2
20 DIAMETRAL PITCH – 28.28 NORMAL DIAMETRAL PITCH HARDENED STEEL .375-.563" FACE
8 .01 29.2 .02 29.1 .05 28.8 .09 28.4 .13 27.9 .25 26.6 .36 25.4 .46 24.3 .64 22.3 1.00 18.0
10 .01 37.7 .03 37.5 .06 37.1 .12 36.3 .17 35.6 .32 33.5 .45 31.7 .57 30.1 .78 27.2 1.20 21.2
12 .02 48.5 .04 48.2 .08 47.5 .15 46.4 .22 45.2 .40 42.2 .56 39.5 .71 37.1 .95 33.2 1.44 25.1
15 .02 62.7 .05 62.2 .10 61.2 .19 59.3 .27 51.6 .50 52.8 .70 48.8 .86 45.4 1.14 39.8 1.66 29.0
20 .02 57.7 .05 57.1 .09 55.9 .17 53.7 .25 51.6 .44 46.2 .60 41.9 .73 38.3 .93 32.7 1.30 22.7
25 .03 73.8 .06 72.8 .11 70.9 .21 67.4 .31 64.3 .54 56.4 .72 50.2 .86 45.2 1.08 37.7 1.44 25.2
30 .04 89.1 .07 87.6 .13 85.0 .25 80.0 .36 75.7 .62 65.0 .81 56.9 .96 50.7 1.19 41.5 1.54 27.0
40 .05 120 .09 118 .18 113 .33 104 .46 97.2 .77 80.5 .98 68.7 1.14 59.9 1.36 47.7 1.69 29.6
50 .06 151 .12 147 .22 139 .40 127 .55 117 .89 93.4 1.11 78.0 1.27 66.9 1.49 52.1 1.79 31.4
60 .07 180 .14 175 .26 165 .47 147 .64 134 .99 104 1.22 85.4 1.38 72.3 1.58 55.4 1.86 32.5
16 DIAMETRAL PITCH – 22.63 NORMAL DIAMETRAL PITCH HARDENED STEEL .500" FACE
12 .03 67.2 .05 66.6 .10 65.6 .20 63.6 .29 61.7 .54 56.6 .75 52.3 .93 48.6 1.20 42.6 1.80 31.1
16 .04 93.4 .07 92.4 .14 90.5 .28 86.9 .40 83.5 .71 74.8 .97 67.8 1.18 62.0 1.51 52.9 2.10 36.7
20 .05 120 .09 118 .18 115 .35 110 .50 104 .87 91.5 1.16 81.5 1.40 73.4 1.75 61.3 2.34 41.0
24 .06 146 .11 144 .22 139 .42 131 .59 124 1.00 107 1.33 93.3 1.58 83.0 1.94 68.1 2.52 44.2
32 .08 197 .15 193 .29 185 .54 172 .76 160 1.26 132 1.61 113 1.87 98.4 2.24 78.4 2.78 48.7
40 .10 249 .19 242 .37 230 .67 210 .92 193 1.47 154 1.84 129 2.11 111 2.46 86.2 3.00 51.8
48 .12 298 .23 289 .43 273 .77 244 1.05 221 1.64 173 2.02 141 2.28 120 2.62 91.8 3.08 53.9
12 DIAMETRAL PITCH – 16.97 NORMAL DIAMETRAL PITCH HARDENED STEEL .750" FACE
12 .07 179 .14 177 .27 173 .53 166 .76 160 1.36 143.2 1.85 130 2.26 119 2.89 101 4.01 70.2
15 .09 231 .18 228 .35 222 .67 211 .96 201 1.68 176 2.24 157 2.69 142 3.37 118 4.51 79.0
18 .11 281 .22 277 .43 268 .80 253 1.14 239 1.95 205 2.57 180 3.05 160 3.75 131 4.86 85.1
24 .15 387 .30 379 .58 364 1.07 337 1.49 313 2.47 260 3.16 222 3.68 193 4.39 154 5.45 95.5
30 .19 489 .38 477 .72 453 1.31 413 1.80 379 2.89 304 3.62 254 4.14 218 4.84 170 5.82 102
36 .23 589 .45 571 .85 538 1.53 482 2.08 437 3.24 341 3.99 279 4.50 237 5.17 181 6.08 106
10 DIAMETRAL PITCH – 14.14 NORMAL DIAMETRAL PITCH HARDENED STEEL .875" FACE
8 .07 181 .14 179 .28 176 .54 171 .79 165 1.44 151 1.78 139 2.45 129 3.20 112 4.62 80.9
10 .10 240 .19 238 .37 233 .71 223 1.02 215 1.83 193 2.49 174 3.03 159 3.88 136 5.39 94.4
12 .12 300 .23 296 .46 288 .87 275 1.25 262 2.20 231 2.95 206 3.55 186 4.46 156 6.01 105
15 .15 387 .30 381 .59 369 1.10 348 1.56 329 2.69 282 3.53 247 4.19 220 5.16 181 6.69 117
20 .21 533 .41 522 .79 501 1.47 464 2.05 432 3.40 357 4.35 305 5.06 266 6.05 212 7.51 131
25 .27 680 .53 662 1.00 630 1.82 573 2.50 526 4.01 422 5.03 352 5.75 302 6.72 235 8.09 142
30 .32 818 .63 793 1.19 747 2.12 669 2.89 606 4.50 473 5.54 388 6.25 328 7.18 252 8.44 148
40 .44 1097 .84 1053 1.55 975 2.69 849 3.58 751 5.32 559 6.36 445 7.04 370 7.89 276 8.97 157
8 DIAMETRAL PITCH – 11.31 NORMAL DIAMETRAL PITCH HARDENED STEEL .750" FACE
8 .10 242 .19 239 .37 234 .71 225 1.03 216 1.85 194 2.51 176 3.06 160 3.91 137 5.43 95
10 .13 321 .25 317 .49 309 .93 293 1.33 280 2.53 245 3.12 218 3.74 197 4.69 164 6.27 110
12 .16 400 .31 394 .61 382 1.14 360 1.62 340 2.78 292 3.65 256 4.34 228 5.33 187 6.92 121
16 .22 555 .43 543 .83 521 1.53 483 2.14 447 3.54 372 4.53 318 5.27 277 6.30 221 7.82 137
20 .28 710 .55 692 1.04 658 1.90 599 2.62 550 4.20 441 5.26 368 6.01 316 7.03 246 8.45 148
24 .34 862 .66 836 1.25 787 2.24 706 3.04 639 4.75 499 5.84 409 6.59 346 7.57 265 8.90 156
32 .46 1160 .88 1113 1.64 1031 2.85 897 3.78 794 5.63 591 6.72 471 7.44 391 8.34 292
40 .58 1454 1.10 1383 2.00 1259 3.39 1068 4.41 927 6.32 664 7.39 517 8.07 424 8.88 311
48 .69 1137 1.30 1636 2.33 1466 3.85 1214 4.93 1036 6.85 719 7.87 551 8.50 447
B
Ratings are based on strength calculation. Basic static strength rating, or for hand operation of above gears is approximately 3 times the 100 RPM rating.
NOTE: Ratings to right of heavy line exceed 1500 Feet per Minute and should be used for interpolation purposes only.
*Torque Rating (Lb. Ins.)
P-1930-BG 04/10 Boston Gear 800-825-6544 67