# Pitch diameter of roller chain wheels

For the convenience of the calculation we give hereafter a table in which, for the most common teeth numbers, and for a chain of one inch pitch, the pitch diameter is indicated. Since the pitch diameter is proportional with the pitch it is sufficient to multiply the figure of the table with the pitch of the chain in English inches expressed as a decimal number.

 z d z d z d z d z d 8 66,37 37 299,51 66 533,82 95 768,22 124 1002,66 9 74,26 38 307,58 67 541,90 96 776,31 125 1010,74 10 82,20 39 315,66 68 549,98 97 784,39 126 1018,82 11 90,16 40 323,74 69 558,06 98 792,47 127 1026,91 12 98,14 41 331,81 70 566,15 99 800,56 128 1034,99 13 106,14 42 339,89 71 574,23 100 808,64 129 1043,08 14 114,15 43 347,97 72 582,31 101 816,72 130 1051,16 15 122,17 44 356,05 73 590,39 102 824,81 131 1059,25 16 130,20 45 364,12 74 598,48 103 832,89 132 1067,33 17 138,23 46 372,20 75 606,56 104 840,98 133 1075,41 18 146,27 47 380,28 76 614,64 105 849,06 134 1083,50 19 154,32 48 388,36 77 622,72 106 857,14 135 1091,58 20 162,37 49 396,44 78 630,81 107 865,23 136 1099,67 21 170,42 50 404,52 79 638,89 108 873,31 137 1107,75 22 178,48 51 412,60 80 646,97 109 881,39 138 1115,84 23 186,54 52 420,68 81 655,05 110 889,48 139 1123,92 24 194,60 53 428,76 82 663,14 111 897,56 140 1132,00 25 202,66 54 436,84 83 671,22 112 905,65 141 1140,09 26 210,72 55 444,92 84 679,30 113 913,73 142 1148,17 27 218,79 56 453,00 85 687,39 114 921,81 143 1156,26 28 226,86 57 461,08 86 695,47 115 929,90 144 1164,34 29 234,93 58 469,16 87 703,55 116 937,98 145 1172,43 30 243,00 59 477,24 88 711,64 117 946,07 146 1180,51 31 251,07 60 485,33 89 719,72 118 954,15 147 1188,60 32 259,14 61 493,41 90 727,80 119 962,24 148 1196,68 33 267,21 62 501,49 91 735,89 120 970,32 149 1204,76 34 275,28 63 509,57 92 743,97 121 978,40 150 1212,85 35 283,36 64 517,65 93 752,05 122 986,49 151 1220,93 36 291,43 65 525,73 94 760,14 123 994,57 152 1229,02
 Pitch of the chain Multiplication coefficient 6 0,2362 8 0,3149 3/8″ 0,3750 1/2″ 0,5000 5/8″ 0,6250 3/4″ 0,7500 1″ 1,0000 1″1/4 1,25 1″1/2 1,5000 1″3/4 1,7500 2″ 2