MARTIN ENGINEERING INFORMATION
Ratio-Center Distance Listings With Approximate Horsepower and Torque  Ratings for Hardened and Ground Worms With Bronze Worm Gears
RPM of Worm 1800 900 300 100
Center *Gear Input-Output Input-Output Input-Output Input-Output
Ratio Distance HP Torque HP Torque HP Torque HP Torque
5 0.938 WB1620Q 0.37 60 0.25 70 0.09 80 0.03 80
5 1.333 WB1220Q 0.8 130 0.55 170 0.25 200 0.08 215
5 1.625 WB1020Q 1.25 200 0.9 275 0.4 350 0.15 370
5 2 WB820Q 2 315 1.5 460 0.8 890 0.33 965
5 2.667 WB620Q 3.7 600 2.75 880 1.4 1280 0.55 1430
6 3 WB624Q 4.5 880 3.4 1300 1.75 1900 0.7 2180
7.5 1.25 WB1630Q 0.5 130 0.33 160 0.14 180 0.05 185
7.5 1.75 WB1230Q 1.25 300 0.85 390 0.33 460 0.13 490
7.5 2.125 WB1030Q 1.9 450 1.33 560 0.6 790 0.25 850
7.5 2.625 WB830Q 3 725 2.25 1060 1 1400 0.4 1520
7.5 3.5 WB630Q 5.75 1400 4.33 2060 2.2 2960 0.87 3330
9.67 4.05 WB529T 8.4 2615 6.25 3785 3.33 5730 1.33 6540
10 0.938 WB1620D 0.25 70 0.15 85 0.06 90 0.02 95
10 1.333 WB1220D 0.5 155 0.33 205 0.16 240 0.6 250
10 1.562 WB1640Q 0.75 240 0.5 285 0.18 320 0.06 330
10 1.625 WB1020D 0.8 230 0.6 325 0.25 400 0.1 430
10 2 WB820D 1.25 365 0.9 525 0.45 690 0.15 750
10 2.167 WB1240Q 1.67 530 1.1 700 0.5 830 0.17 880
10 2.625 WB1040Q 2.5 805 1.75 1120 0.8 1400 0.3 1500
10 2.667 WB620D 2.4 735 1.8 1075 0.95 1540 0.37 1700
10 3.25 WB840Q 4 1300 3 1880 1.4 2500 0.5 2700
10 4.333 WB640Q 7.75 2500 5.75 3675 3 5333 1.15 5980
12 3 WB624D 2.85 1050 2.2 1550 1.15 2200 0.45 2450
12.5 1.875 WB1650Q 0.95 375 0.6 445 0.25 500 0.08 515
12.5 2.583 WB1250Q 2 820 1.4 1080 0.6 1300 0.2 1370
12.5 3.125 WB1050Q 3 1250 2.25 1740 1 2200 0.33 2340
12.5 3.875 WB850Q 4.9 2000 3.7 2900 1.7 3840 0.65 4170
12.5 5.167 WB650Q 9.5 3800 7 5600 3.6 8200 1.4 9200
13.33 5.15 WB540T 11 4720 8.2 6830 4.4 10360 1.75 11800
15 1.25 WB1630D 0.33 155 0.25 180 0.08 200 0.03 210
15 1.75 WB1230D 0.75 350 0.5 450 0.25 535 0.07 560
15 2.125 WB1030D 1.2 520 0.87 725 0.37 900 0.15 965
15 2.188 WB1660Q 1.1 570 0.7 680 0.25 760 0.1 790
15 2.625 WB830D 1.67 750 1.25 1080 0.6 1415 0.25 1530
15 3 WB1260Q 2.5 1170 1.67 1540 0.7 1800 0.25 1930
15 3.5 WB630D 3.5 1620 2.7 2375 1.4 3370 0.55 3770
15 3.625 WB1060Q 3.75 1700 2.67 2500 1.17 3100 0.5 3300
15 4.5 WB860Q 5.75 2820 4.33 4100 2 5470 0.75 6000
15 6 WB660Q 11.33 5550 8.5 8000 4.33 11700 1.7 13100
16.67 6.15 WB550T 13.5 7250 10 10500 5.4 16000 2.2 18000
18 5 WB318 6 3100 4.67 4570 3 8000 1.5 10000
18 7 WB672Q 13.5 7800 10 11400 5 16500 2 18500
20 0.938 WB1620 0.15 75 0.1 90 0.04 100 0.02 105
20 1.333 WB1220 0.33 170 0.25 220 0.1 260 0.04 275
20 1.562 WB1640D 0.5 270 0.3 310 0.1 350 0.04 350
20 1.625 WB1020 0.5 250 0.33 350 0.2 440 0.07 470
20 2 WB820 0.75 400 0.6 600 0.33 775 0.12 850
20 2.167 WB1240D 1 600 0.67 775 0.33 920 0.1 970
20 2.625 WB1040D 1.5 900 0.85 1230 0.5 1500 0.2 1650
20 2.667 WB620 1.5 800 1.15 1170 0.75 1660 0.25 1850
20 2.812 WB1680Q 1.4 900 0.9 1075 0.33 1200 0.12 1240
20 3.25 WB840D 2.3 1400 1.75 2000 0.8 2580 0.33 2800
20 3.833 WB1280Q 3.12 2000 2.12 2600 0.9 3120 0.33 3300
20 4 WB420 3.5 2000 2.75 2880 1.75 4700 0.75 5600
20 4.333 WB640D 4.5 2780 3.4 4050 1.75 5800 0.7 6500
20 4.625 WB1080Q 4.75 3000 3.4 4250 1.5 5340 0.5 5700
20 5.75 WB880Q 7.5 4800 5.6 7000 2.6 9400 1 10200
20 7.667 WB680Q 15 9500 10.75 13800 5.5 20000 2.2 22500
24 3 WB624 1.75 1120 1.33 1630 0.75 2300 0.33 2600
24 4.5 WB424 4 2800 3 4000 2 6600 0.9 7800
24 6 WB324 7.5 5300 5.9 7750 3.9 13500 1.9 17000
25 1.875 WB1650D 0.5 370 0.33 470 0.12 520 0.05 540
25 2.583 WB1250D 1.2 890 0.8 1150 0.33 1380 0.12 1450
25 3.125 WB1050D 1.8 1340 1.33 1850 0.6 2300 0.25 2500
25 3.438 WB16100Q 1.75 1300 1 1575 0.4 1750 0.12 1800
25 3.875 WB850D 3 2200 2.25 3250 1 4200 0.4 4500
25 4.667 WB12100Q 3.67 2800 2.5 3660 1 4400 0.4 4630
25 5.167 WB650D 5.5 4000 4 6000 2.15 8700 0.87 9700
25 5.625 WB10100Q 5.7 4500 4.1 6380 1.75 8000 0.67 8500
25 7 WB8100Q 10 9700 7 11500 4 17500 1.25 19000
25 9.333 WB6100Q 17.5 14250 13 20750 6.66 30000 2.6 33000
29 4.05 WB529 3.5 2800 2.75 4200 1.5 6300 0.67 7000
30 1.25 WB1630 0.2 160 0.12 190 0.06 210 0.02 215
30 1.75 WB1230 0.5 350 0.33 450 0.15 540 0.06 570
30 2.125 WB1030 0.7 530 0.5 750 0.25 925 0.1 1000
30 2.188 WB1660 0.6 590 0.4 700 0.15 760 0.05 800
30 2.625 WB830 1 870 0.85 1260 0.4 1600 0.17 1750
30 3 WB1260D 1.33 1230 1 1600 0.4 1900 0.15 2000
30 3.5 WB630 2 1700 1.6 2430 0.87 3500 0.33 3800
30 3.625 WB1060D 2 1850 1.5 2500 0.7 3200 0.25 3430
30 4.5 WB860D 3.25 2900 2.5 4300 1.12 5650 0.5 6000
30 6 WB660D 6.3 5800 4.8 6075 2.5 12110 1 13510
30 7 WB330 9.05 7880 7 11570 4.6 20280 2.25 25560
32 5.5 WB432 5.15 4680 4 6750 2.5 11140 1.1 13200
36 4 WB636 2.33 2310 1.8 3380 1 4800 0.42 5360
36 7 WB672D 7.25 8010 5.5 11670 2.87 16700 1.15 18650
36 8 WB336 10.4 10900 8.1 15960 5.35 27950 2.6 35280
40 1.562 WB1640 0.25 266 0.12 330 0.07 350 0.02 360
40 2.167 WB1240 0.55 580 0.3 825 0.18 900 0.07 940
40 2.625 WB1040 0.87 890 0.65 1220 0.3 1520 0.12 1630
40 2.812 WB1680D 0.75 910 0.33 1140 0.2 1200 0.07 1230
40 3.25 WB840 1.35 1440 0.85 2350 0.5 2700 0.2 2900
40 3.833 WB1280D 1.7 2040 1.15 2675 0.5 3160 0.2 3330
40 4.333 WB640 2.5 2770 2 4033 1 5760 0.45 6420
40 4.625 WB1080D 2.6 3070 1.9 4270 0.85 5315 0.33 5680
40 5.15 WB540 4.33 4930 3.4 7145 2 10725 0.83 12170
40 5.75 WB880D 4 4740 3 6850 1.4 8940 0.55 9680
40 6.5 WB440 6 5520 4.65 7950 3 13200 1.33 15480
40 7.667 WB680D 7.83 9600 6 14000 3 20025 1.25 22340
48 3.75 WB848 1.5 1950 1.2 2820 0.6 3650 0.25 3960
48 5 WB648 2.8 3730 2.25 5460 1.25 7750 0.5 8640
48 7.5 WB448 6.8 9320 5.25 13400 3.33 22200 1.5 26160
48 10 WB348 12.7 17640 9.87 25920 6.5 45360 3.16 57120
50 1.875 WB1650 0.3 380 0.2 450 0.08 490 0.03 515
50 2.583 WB1250 0.66 840 0.5 1090 0.2 1300 0.08 1360
50 3.125 WB1050 1 1280 0.75 1770 0.33 2200 0.14 2340
50 3.438 WB16100D 0.9 1290 0.5 1525 0.25 1690 0.08 1730
50 3.875 WB850 1.6 2140 1.25 3130 0.66 4090 0.25 4430
50 4.667 WB12100D 2 2875 1.33 3600 0.5 4460 0.22 4700
50 5.167 WB650 2.9 4000 2.25 5825 1.25 8310 0.5 9260
50 5.625 WB10100D 3 4440 2.16 6110 1 7675 0.33 8000
50 6.15 WB550 5.12 7120 4 10320 2.25 15480 1 17570
50 7 WB8100D 4.1 5000 2.75 7500 1.5 8000 0.6 10000
50 9.333 WB6100D 9 13800 6.75 20200 3.5 28930 1.4 32280
54 11 WB354 13.5 21230 10.5 31200 7 54480 3.33 68760
59 7.05 WB559 5.5 9230 4.5 13900 2.5 20075 1 23160
60 2.188 WB1660 0.33 550 0.2 650 0.08 720 0.03 740
60 3 WB1260 0.75 1100 0.5 1440 0.25 1700 0.09 1790
60 3.625 WB1060 1 1690 0.8 2330 0.33 2890 0.16 3080
60 4.5 WB860 1.66 2660 1.33 3900 0.66 5090 0.25 5500
60 6 WB660 320 5240 2.5 7670 1.4 1080 0.6 1225
64 9.5 WB464 7.87 14280 6 20640 3.8 34080 1.7 40320
72 7 WB672 3.33 6610 2.5 9660 1.5 13700 0.6 15360
80 2.812 WB1680 0.33 705 0.22 830 0.09 920 0.04 950
80 3.833 WB1280 0.75 1550 0.5 2030 0.25 2375 0.1 2520
80 4.625 WB1080 1.15 2375 0.87 3275 0.4 4050 0.16 4330
80 5.75 WB880 1.8 3800 1.4 5500 0.7 7140 0.3 7750
80 7.667 WB680 3.33 7380 2.66 10750 1.5 15350 0.6 17110
96 6.75 WB896 1.5 4200 1 6000 0.5 7000 0.2 8500
96 9 WB696 3.25 8490 2.5 12370 1.33 17660 0.5 19680
100 3.438 WB16100 0.33 810 0.2 960 0.09 1060 0.33 1100
100 4.667 WB12100 0.75 1790 0.5 2330 0.25 2730 0.9 2800
100 5.625 WB10100 1 2780 0.8 3850 0.33 4775 0.16 5100
100 7 WB8100 1.67 4450 1.25 6300 0.67 8000 0.24 9000
100 9.333 WB6100 3.2 8700 2.5 12675 1.33 18090 0.55 20160
* Ratings listed are for bronze worm gears operating with hardened and ground steel worms. For ratings of cast iron worm gears with hardened steel worm, multiply listed ratings by 30%. For cast iron with hardened and ground steel worm, multiply by 50%.
  Torque ratings in inch pounds.