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Heavy Weight Drill collar is an essential part of the performance of Jcdrill down hole drilling tools. Drill collars provide weight on bit for drilling through formations. Rig drillers are able to monitor weight applied to bit by monitoring through simple calculations, and a weight indicator scale, on rig floor. Drill collars are typically 31’ feet in length,thick walled, and heavy steel. They come box by pin with like connections, in order to mate as many needed, to achieve desired weight. Drill collars come slick OD, or machined with helical grooves (spiral collars). Jink ekeeps a generous supply of carbon steel drill collars in stock. Lead Collar Lead collars purpose is to put a short amount of space between the drilling bit, and near bit stabilizer. This is just another way Jcdrill gives you the ability to tweak your performance needs as down hole challenges arise. By adding this short spacing between bit, and near bit stab, you stiffen the BHA wright at the bit, reducing bit walk, therefore, promoting a straighter hole. Jcdrill keeps a generous supply of carbon steel lead collars in stock.
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Design | O | D | ID | Lengh | Chamfer Diameter |
in | mm | +1.6-0.0mm | +152.4mm | +0.4mm | |
NC23-31 | 3 1/8 | 79.4 | 31.8 | 9.15 | 76.2 |
NC26-35 | 3 1/2 | 88.9 | 38.1 | 9.15 | 82.9 |
NC31-41 | 4 1/8 | 104.8 | 50.8 | 9.159.45 | 100.4 |
NC35-47 | 4 3/4 | 120.7 | 50.8 | 9.159.45 | 114.7 |
NC38-50 | 5 | 127 | 57.2 | 9.159.45 | 121 |
NC44-60 | 6 | 152.4 | 57.2 | 9.159.45 | 144.5 |
NC44-60 | 6 | 152.4 | 71.4 | 9.159.45 | 144.5 |
NC44-62 | 6 1/4 | 158.8 | 57.2 | 9.159.45 | 149.2 |
NC44-62 | 6 1/4 | 158.5 | 71.4 | 9.159.45 | 150 |
NC46-65 | 6 1/2 | 165.1 | 57.2 | 9.159.45 | 154.8 |
NC46-65 | 6 1/2 | 165.1 | 71.4 | 9.159.45 | 154.8 |
NC46-67 | 6 3/4 | 171.5 | 57.2 | 9.159.45 | 159.5 |
NC50-70 | 7 | 177.8 | 57.2 | 9.159.45 | 164.7 |
NC50-70 | 7 | 177.8 | 71.4 | 9.159.45 | 164.7 |
NC50-72 | 7 1/4 | 184.2 | 71.4 | 9.159.45 | 169.5 |
NC56-77 | 7 3/4 | 196.9 | 71.4 | 9.159.45 | 185.3 |
NC56-80 | 8 | 203.2 | 71.4 | 9.159.45 | 190.1 |
6 5/8REG | 8 1/4 | 209.6 | 71.4 | 9.159.45 | 195.7 |
NC61-90 | 9 | 228.6 | 71.4 | 9.159.45 | 212.7 |
7 5/8REG | 9 1/2 | 241.3 | 76.2 | 9.159.45 | 223.8 |
NC70-97 | 9 3/4 | 247.7 | 76.2 | 9.159.45 | 232.6 |
NC70-100 | 10 | 254 | 76.2 | 9.159.45 | 237.3 |
8 5/8REGc | 11 | 279.4 | 76.2 | 9.159.45 | 266.7 |
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