{"id":18377,"date":"2026-09-15T12:41:17","date_gmt":"2026-09-15T04:41:17","guid":{"rendered":"https:\/\/aobosteel.com\/?page_id=18377"},"modified":"2026-10-20T09:00:28","modified_gmt":"2026-10-20T01:00:28","slug":"tap-drill-size-chart","status":"publish","type":"page","link":"https:\/\/aobosteel.com\/pt\/tap-drill-size-chart\/","title":{"rendered":"tabela de tamanhos de broca de rosca"},"content":{"rendered":"

tabela de tamanhos de broca de rosca<\/h1>\n\n\n\n

A broca a usar antes de um macho, para roscas UNC e UNF de #0 a 2-1\/2 in., para roscas m\u00e9tricas ISO de passo grosso de M1 a M68, e para tamanhos de parafusos de m\u00e1quina com suas brocas de folga. Os tamanhos de broca s\u00e3o dados como broca fracion\u00e1ria, num\u00e9rica ou alfab\u00e9tica, com seus equivalentes decimais e em mil\u00edmetros.<\/p>\n\n\n\n

Brocas de pr\u00e9-fura\u00e7\u00e3o para roscas UNC e UNF, tamanhos fracion\u00e1rios<\/h2>\n\n\n\n

Rosca de forma American National, cobrindo os passos comuns UNC e UNF, com as s\u00e9ries grossa e fina mais antigas inclu\u00eddas. Os tamanhos de broca permitem aproximadamente 75 por cento de uma rosca completa. Para os tamanhos pequenos, escolher os tamanhos de furo maiores da tabela de limites de tamanho de furo reduz a quebra de macho. Fonte, Tabela 3.<\/p>\n\n\n\n

Fio<\/th>Di\u00e2metro de raiz, in.<\/th>Broca de pr\u00e9-fura\u00e7\u00e3o<\/th>Di\u00e2metro da broca, in.<\/th>Di\u00e2metro da broca, mm<\/th><\/tr><\/thead>
1\/16 – 64<\/td>0.0422<\/td>3\/64<\/td>0.0469<\/td>1.19<\/td><\/tr>
1\/16 – 72<\/td>0.0445<\/td>3\/64<\/td>0.0469<\/td>1.19<\/td><\/tr>
5\/64 – 60<\/td>0.0563<\/td>1\/16<\/td>0.0625<\/td>1.59<\/td><\/tr>
5\/64 – 72<\/td>0.0601<\/td>52<\/td>0.0635<\/td>1.61<\/td><\/tr>
3\/32 – 48<\/td>0.0667<\/td>49<\/td>0.0730<\/td>1.85<\/td><\/tr>
3\/32 – 50<\/td>0.0678<\/td>49<\/td>0.0730<\/td>1.85<\/td><\/tr>
7\/64 – 48<\/td>0.0823<\/td>43<\/td>0.0890<\/td>2.26<\/td><\/tr>
1\/8 – 32<\/td>0.0844<\/td>3\/32<\/td>0.0937<\/td>2.38<\/td><\/tr>
1\/8 – 40<\/td>0.0925<\/td>38<\/td>0.1015<\/td>2.58<\/td><\/tr>
9\/64 – 40<\/td>0.1081<\/td>32<\/td>0.1160<\/td>2.95<\/td><\/tr>
5\/32 – 32<\/td>0.1157<\/td>1\/8<\/td>0.1250<\/td>3.17<\/td><\/tr>
5\/32 – 36<\/td>0.1202<\/td>30<\/td>0.1285<\/td>3.26<\/td><\/tr>
11\/64 – 32<\/td>0.1313<\/td>9\/64<\/td>0.1406<\/td>3.57<\/td><\/tr>
3\/16 – 24<\/td>0.1334<\/td>26<\/td>0.1470<\/td>3.73<\/td><\/tr>
3\/16 – 32<\/td>0.1469<\/td>22<\/td>0.1570<\/td>3.99<\/td><\/tr>
13\/64 – 24<\/td>0.1490<\/td>20<\/td>0.1610<\/td>4.09<\/td><\/tr>
7\/32 – 24<\/td>0.1646<\/td>16<\/td>0.1770<\/td>4.50<\/td><\/tr>
7\/32 – 32<\/td>0.1782<\/td>12<\/td>0.1890<\/td>4.80<\/td><\/tr>
15\/64 – 24<\/td>0.1806<\/td>10<\/td>0.1935<\/td>4.91<\/td><\/tr>
1\/4 – 20<\/td>0.1850<\/td>7<\/td>0.2010<\/td>5.11<\/td><\/tr>
1\/4 – 24<\/td>0.1959<\/td>4<\/td>0.2090<\/td>5.31<\/td><\/tr>
1\/4 – 27<\/td>0.2019<\/td>3<\/td>0.2130<\/td>5.41<\/td><\/tr>
1\/4 – 28<\/td>0.2036<\/td>3<\/td>0.2130<\/td>5.41<\/td><\/tr>
1\/4 – 32<\/td>0.2094<\/td>7\/32<\/td>0.2187<\/td>5.55<\/td><\/tr>
5\/16 – 18<\/td>0.2403<\/td>F<\/td>0.2570<\/td>6.53<\/td><\/tr>
5\/16 – 20<\/td>0.2476<\/td>17\/64<\/td>0.2656<\/td>6.75<\/td><\/tr>
5\/16 – 24<\/td>0.2584<\/td>I<\/td>0.2720<\/td>6.91<\/td><\/tr>
5\/16 – 27<\/td>0.2644<\/td>J<\/td>0.2770<\/td>7.04<\/td><\/tr>
5\/16 – 32<\/td>0.2719<\/td>9\/32<\/td>0.2812<\/td>7.14<\/td><\/tr>
3\/8 – 16<\/td>0.2938<\/td>5\/16<\/td>0.3125<\/td>7.94<\/td><\/tr>
3\/8 – 20<\/td>0.3100<\/td>21\/64<\/td>0.3281<\/td>8.33<\/td><\/tr>
3\/8 – 24<\/td>0.3209<\/td>Q<\/td>0.3320<\/td>8.43<\/td><\/tr>
3\/8 – 27<\/td>0.3269<\/td>R<\/td>0.3390<\/td>8.61<\/td><\/tr>
7\/16 – 14<\/td>0.3447<\/td>U<\/td>0.3680<\/td>9.35<\/td><\/tr>
7\/16 – 20<\/td>0.3726<\/td>25\/64<\/td>0.3906<\/td>9.92<\/td><\/tr>
7\/16 – 24<\/td>0.3834<\/td>X<\/td>0.3970<\/td>10.08<\/td><\/tr>
7\/16 – 27<\/td>0.3894<\/td>Y<\/td>0.4040<\/td>10.26<\/td><\/tr>
1\/2 – 12<\/td>0.3918<\/td>27\/64<\/td>0.4219<\/td>10.72<\/td><\/tr>
1\/2 – 13<\/td>0.4001<\/td>27\/64<\/td>0.4219<\/td>10.72<\/td><\/tr>
1\/2 – 20<\/td>0.4351<\/td>29\/64<\/td>0.4531<\/td>11.51<\/td><\/tr>
1\/2 – 24<\/td>0.4459<\/td>29\/64<\/td>0.4531<\/td>11.51<\/td><\/tr>
1\/2 – 27<\/td>0.4519<\/td>15\/32<\/td>0.4687<\/td>11.90<\/td><\/tr>
9\/16 – 12<\/td>0.4542<\/td>31\/64<\/td>0.4844<\/td>12.30<\/td><\/tr>
9\/16 – 18<\/td>0.4903<\/td>33\/64<\/td>0.5156<\/td>13.10<\/td><\/tr>
9\/16 – 27<\/td>0.5144<\/td>17\/32<\/td>0.5312<\/td>13.49<\/td><\/tr>
5\/8 – 11<\/td>0.5069<\/td>17\/32<\/td>0.5312<\/td>13.49<\/td><\/tr>
5\/8 – 12<\/td>0.5168<\/td>35\/64<\/td>0.5469<\/td>13.89<\/td><\/tr>
5\/8 – 18<\/td>0.5528<\/td>37\/64<\/td>0.5781<\/td>14.68<\/td><\/tr>
5\/8 – 27<\/td>0.5769<\/td>19\/32<\/td>0.5937<\/td>15.08<\/td><\/tr>
11\/16 – 11<\/td>0.5694<\/td>19\/32<\/td>0.5937<\/td>15.08<\/td><\/tr>
11\/16 – 16<\/td>0.6063<\/td>5\/8<\/td>0.6250<\/td>15.88<\/td><\/tr>
3\/4 – 10<\/td>0.6201<\/td>21\/32<\/td>0.6562<\/td>16.67<\/td><\/tr>
3\/4 – 12<\/td>0.6418<\/td>43\/64<\/td>0.6719<\/td>17.07<\/td><\/tr>
3\/4 – 16<\/td>0.6688<\/td>11\/16<\/td>0.6875<\/td>17.46<\/td><\/tr>
3\/4 – 27<\/td>0.7019<\/td>23\/32<\/td>0.7187<\/td>18.25<\/td><\/tr>
13\/16 – 10<\/td>0.6826<\/td>23\/32<\/td>0.7187<\/td>18.25<\/td><\/tr>
7\/8 – 9<\/td>0.7307<\/td>49\/64<\/td>0.7656<\/td>19.45<\/td><\/tr>
7\/8 – 12<\/td>0.7668<\/td>51\/64<\/td>0.7969<\/td>20.24<\/td><\/tr>
7\/8 – 14<\/td>0.7822<\/td>13\/16<\/td>0.8125<\/td>20.64<\/td><\/tr>
7\/8 – 18<\/td>0.8028<\/td>53\/64<\/td>0.8281<\/td>21.03<\/td><\/tr>
7\/8 – 27<\/td>0.8269<\/td>27\/32<\/td>0.8437<\/td>21.43<\/td><\/tr>
15\/16 – 9<\/td>0.7932<\/td>53\/64<\/td>0.8281<\/td>21.03<\/td><\/tr>
1 – 8<\/td>0.8376<\/td>7\/8<\/td>0.8750<\/td>22.22<\/td><\/tr>
1 – 12<\/td>0.8918<\/td>59\/64<\/td>0.9219<\/td>23.42<\/td><\/tr>
1 – 14<\/td>0.9072<\/td>15\/16<\/td>0.9375<\/td>23.81<\/td><\/tr>
1 – 27<\/td>0.9519<\/td>31\/32<\/td>0.9687<\/td>24.60<\/td><\/tr>
1 1\/8 – 7<\/td>0.9394<\/td>63\/64<\/td>0.9844<\/td>25.00<\/td><\/tr>
1 1\/8 – 12<\/td>1.0168<\/td>1 3\/64<\/td>1.0469<\/td>26.59<\/td><\/tr>
1 1\/4 – 7<\/td>1.0644<\/td>1 7\/64<\/td>1.1094<\/td>28.18<\/td><\/tr>
1 1\/4 – 12<\/td>1.1418<\/td>1 11\/64<\/td>1.1719<\/td>29.77<\/td><\/tr>
1 3\/8 – 6<\/td>1.1585<\/td>1 7\/32<\/td>1.2187<\/td>30.95<\/td><\/tr>
1 3\/8 – 12<\/td>1.2668<\/td>1 19\/64<\/td>1.2969<\/td>32.94<\/td><\/tr>
1 1\/2 – 6<\/td>1.2835<\/td>1 11\/32<\/td>1.3437<\/td>34.13<\/td><\/tr>
1 1\/2 – 12<\/td>1.3918<\/td>1 27\/64<\/td>1.4219<\/td>36.12<\/td><\/tr>
1 5\/8 – 5 1\/2<\/td>1.3888<\/td>1 29\/64<\/td>1.4531<\/td>36.91<\/td><\/tr>
1 3\/4 – 5<\/td>1.4902<\/td>1 9\/16<\/td>1.5625<\/td>39.69<\/td><\/tr>
1 7\/8 – 5<\/td>1.6152<\/td>1 11\/16<\/td>1.6875<\/td>42.86<\/td><\/tr>
2 – 4 1\/2<\/td>1.7113<\/td>1 25\/32<\/td>1.7812<\/td>45.24<\/td><\/tr>
2 1\/8 – 4 1\/2<\/td>1.8363<\/td>1 29\/32<\/td>1.9062<\/td>48.42<\/td><\/tr>
2 1\/4 – 4 1\/2<\/td>1.9613<\/td>2 1\/32<\/td>2.0312<\/td>51.59<\/td><\/tr>
2 3\/8 – 4<\/td>2.0502<\/td>2 1\/8<\/td>2.1250<\/td>53.97<\/td><\/tr>
2 1\/2 – 4<\/td>2.1752<\/td>2 1\/4<\/td>2.2500<\/td>57.15<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

O di\u00e2metro da broca em mm \u00e9 convertido do valor em polegadas a 1 in. = 25,4 mm. As roscas de #0 a 1 in. tamb\u00e9m est\u00e3o listadas abaixo com suas brocas de folga.<\/p>\n\n\n\n

Brocas de pr\u00e9-fura\u00e7\u00e3o e brocas de folga para parafusos de m\u00e1quina<\/h2>\n\n\n\n

Parafusos de m\u00e1quina numerados e fracion\u00e1rios pequenos: a broca de pr\u00e9-fura\u00e7\u00e3o para a rosca, e as brocas de folga de ajuste justo e ajuste livre usadas quando o parafuso passa atrav\u00e9s da pe\u00e7a. Onde um tamanho tem mais de um passo, os valores s\u00e3o listados para cada passo na ordem mostrada. Fonte, Tabela 4.<\/p>\n\n\n\n

Tamanho<\/th>Di\u00e2metro, in.<\/th>Roscas por in.<\/th>Broca de pr\u00e9-fura\u00e7\u00e3o<\/th>Di\u00e2metro da broca, in.<\/th>Broca de ajuste justo<\/th>Di\u00e2metro, in.<\/th>Broca de ajuste livre<\/th>Di\u00e2metro, in.<\/th><\/tr><\/thead>
0<\/td>.060<\/td>80<\/td>3\u204464<\/td>.0469<\/td>52<\/td>.0635<\/td>50<\/td>.0700<\/td><\/tr>
1<\/td>.073<\/td>64\n72<\/td>53\n53<\/td>.0595\n.0595<\/td>48<\/td>.0760<\/td>46<\/td>.0810<\/td><\/tr>
2<\/td>.086<\/td>56\n64<\/td>50\n50<\/td>.0700\n.0700<\/td>43<\/td>.0890<\/td>41<\/td>.0960<\/td><\/tr>
3<\/td>.099<\/td>48\n56<\/td>47\n45<\/td>.0785\n.0820<\/td>37<\/td>.1040<\/td>35<\/td>.1100<\/td><\/tr>
4<\/td>.112<\/td>36a\n40\n48<\/td>44\n43\n42<\/td>.0860\n.0890\n.0935<\/td>32<\/td>.1160<\/td>30<\/td>.1285<\/td><\/tr>
5<\/td>.125<\/td>40\n44<\/td>38\n37<\/td>.1015\n.1040<\/td>30<\/td>.1285<\/td>29<\/td>.1360<\/td><\/tr>
6<\/td>.138<\/td>32\n40<\/td>36\n33<\/td>.1065\n.1130<\/td>27<\/td>.1440<\/td>25<\/td>.1495<\/td><\/tr>
8<\/td>.164<\/td>32\n36<\/td>29\n29<\/td>.1360\n.1360<\/td>18<\/td>.1695<\/td>16<\/td>.1770<\/td><\/tr>
10<\/td>.190<\/td>24\n32<\/td>25\n21<\/td>.1495\n.1590<\/td>9<\/td>.1960<\/td>7<\/td>.2010<\/td><\/tr>
12<\/td>.216<\/td>24\n28<\/td>16\n14<\/td>.1770\n.1820<\/td>2<\/td>.2210<\/td>1<\/td>.2280<\/td><\/tr>
14<\/td>.242<\/td>20a\n24a<\/td>10\n7<\/td>.1935\n.2010<\/td>D<\/td>.2460<\/td>F<\/td>.2570<\/td><\/tr>
1\u20444<\/td>.250<\/td>20\n28<\/td>7\n3<\/td>.2010\n.2130<\/td>F<\/td>.2570<\/td>H<\/td>.2660<\/td><\/tr>
5\u204416<\/td>.3125<\/td>18\n24<\/td>F\nI<\/td>.2570\n.2720<\/td>P<\/td>.3230<\/td>Q<\/td>.3320<\/td><\/tr>
3\u20448<\/td>.375<\/td>16\n24<\/td>5\u204416\nQ<\/td>.3125\n.3320<\/td>W<\/td>.3860<\/td>X<\/td>.3970<\/td><\/tr>
7\u204416<\/td>.4375<\/td>14\n20<\/td>U\n25\u204464<\/td>.3680\n.3906<\/td>29\u204464<\/td>.4531<\/td>15\u204432<\/td>.4687<\/td><\/tr>
1\u20442<\/td>.500<\/td>13\n20<\/td>27\u204464\n29\u204464<\/td>.4219\n.4531<\/td>33\u204464<\/td>.5156<\/td>17\u204432<\/td>.5312<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Brocas de pr\u00e9-fura\u00e7\u00e3o para roscas m\u00e9tricas ISO de passo grosso<\/h2>\n\n\n\n

Tamanhos de broca de roscar recomendados e alternativos para roscas m\u00e9tricas de passo grosso, em mil\u00edmetros. Os tamanhos recomendados d\u00e3o um engajamento radial te\u00f3rico de cerca de 81 por cento, os tamanhos alternativos cerca de 70 a 75 por cento. A tabela \u00e9 apenas para machos de canais, um macho sem canais (conforma\u00e7\u00e3o a frio) requer um tamanho de furo diferente. Fonte, Tabela 6.<\/p>\n\n\n\n

Fio<\/th>Broca recomendada, mm<\/th>Engajamento radial, %<\/th>Broca alternativa, mm<\/th>Engajamento radial, %<\/th><\/tr><\/thead>
M1<\/td>0.75<\/td>81.5<\/td>0.78<\/td>71.7<\/td><\/tr>
M1.1<\/td>0.85<\/td>81.5<\/td>0.88<\/td>71.7<\/td><\/tr>
M1.2<\/td>0.95<\/td>81.5<\/td>0.98<\/td>71.7<\/td><\/tr>
M1.4<\/td>1.10<\/td>81.5<\/td>1.15<\/td>67.9<\/td><\/tr>
M1.6<\/td>1.25<\/td>81.5<\/td>1.30<\/td>69.9<\/td><\/tr>
M1.8<\/td>1.45<\/td>81.5<\/td>1.50<\/td>69.9<\/td><\/tr>
M2<\/td>1.60<\/td>81.5<\/td>1.65<\/td>71.3<\/td><\/tr>
M2.2<\/td>1.75<\/td>81.5<\/td>1.80<\/td>72.5<\/td><\/tr>
M2.5<\/td>2.05<\/td>81.5<\/td>2.10<\/td>72.5<\/td><\/tr>
M3<\/td>2.50<\/td>81.5<\/td>2.55<\/td>73.4<\/td><\/tr>
M3.5<\/td>2.90<\/td>81.5<\/td>2.95<\/td>74.7<\/td><\/tr>
M4<\/td>3.30<\/td>81.5<\/td>3.40<\/td>69.9b<\/td><\/tr>
M4.5<\/td>3.70<\/td>86.8<\/td>3.80<\/td>76.1<\/td><\/tr>
M5<\/td>4.20<\/td>81.5<\/td>4.30<\/td>71.3b<\/td><\/tr>
M6<\/td>5.00<\/td>81.5<\/td>5.10<\/td>73.4<\/td><\/tr>
M7<\/td>6.00<\/td>81.5<\/td>6.10<\/td>73.4<\/td><\/tr>
M8<\/td>6.80<\/td>78.5<\/td>6.90<\/td>71.7b<\/td><\/tr>
M9<\/td>7.80<\/td>78.5<\/td>7.90<\/td>71.7b<\/td><\/tr>
M10<\/td>8.50<\/td>81.5<\/td>8.60<\/td>76.1<\/td><\/tr>
M11<\/td>9.50<\/td>81.5<\/td>9.60<\/td>76.1<\/td><\/tr>
M12<\/td>10.20<\/td>83.7<\/td>10.40<\/td>74.5b<\/td><\/tr>
M14<\/td>12.00<\/td>81.5<\/td>12.20<\/td>73.4b<\/td><\/tr>
M16<\/td>14.00<\/td>81.5<\/td>14.25<\/td>71.3c<\/td><\/tr>
M18<\/td>15.50<\/td>81.5<\/td>15.75<\/td>73.4c<\/td><\/tr>
M20<\/td>17.50<\/td>81.5<\/td>17.75<\/td>73.4c<\/td><\/tr>
M22<\/td>19.50<\/td>81.5<\/td>19.75<\/td>73.4c<\/td><\/tr>
M24<\/td>21.00<\/td>81.5<\/td>21.25<\/td>74.7b<\/td><\/tr>
M27<\/td>24.00<\/td>81.5<\/td>24.25<\/td>74.7b<\/td><\/tr>
M30<\/td>26.50<\/td>81.5<\/td>26.75<\/td>75.7b<\/td><\/tr>
M33<\/td>29.50<\/td>81.5<\/td>29.75<\/td>75.7b<\/td><\/tr>
M36<\/td>32.00<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M39<\/td>35.00<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M42<\/td>37.50<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M45<\/td>40.50<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M48<\/td>43.00<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M52<\/td>47.00<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M56<\/td>50.50<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M60<\/td>54.50<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M64<\/td>58.00<\/td>81.5<\/td>...<\/td>...<\/td><\/tr>
M68<\/td>62.00<\/td>81.5<\/td>...<\/td>...<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Notas de rodap\u00e9 na fonte: (b) apenas para roscas de classe de toler\u00e2ncia 6H e 7H; (c) apenas para roscas de classe de toler\u00e2ncia 7H; as retic\u00eancias marcam tamanhos onde nenhuma broca alternativa est\u00e1 listada.<\/p>\n\n\n\n