Drill collars is one of the most important product of weigao oil drillings which mainly used to provide bit weight to drill so that drill pipe is in tension. Especially drill collar can keep drill bit centralized and hole track by large rigidity. Weigao brand drill collars are manufactured strictly from API Spec7-1 standard. The performance of drill collars will effect the efficiency of drilling.Weigao own the leading heat treatment equipment which import for worldwide. Our mission is to provide our clients with most cost-effective products, not only price, but also products performance.The product quality and stability, the customers satisfaction is 100%.
The drill collar is made of modified AISI 4145H chromium molybdenum alloy steel. These drill collar bars are full-length heat treated and water quenched to obtain ASTM A-370 mechanical properties. Full mechanical and chemical mill test certifications are supplied with all drill collars. These mill test certifications guarantee a hardness range of 285 to 341 BHN and an impact value of 40 ft.-lbs. at room temperature one inch below the surface.
|
Type
|
OD(mm)
|
ID(mm)
|
L(m) ±152.4mm d
|
DF(mm) ±0.4
|
|
NC23-31
|
79.4
|
31.8
|
9.14
|
76.2
|
|
NC26-35
|
88.9
|
38.1
|
9.14
|
82.9
|
|
NC31-41
|
104.8
|
50.8
|
9.14or9.45
|
100.4
|
|
NC35-47
|
120.6
|
50.8
|
9.14or9.45
|
114.7
|
|
NC38-50
|
127
|
57.2
|
9.14or9.45
|
121
|
|
NC44-60
|
152.4
|
57.2
|
9.14or9.45
|
144.5
|
|
NC44-60
|
152.4
|
71.4
|
9.14or9.45
|
144.5
|
|
NC46-62
|
158.8
|
57.2
|
9.14or9.45
|
149.2
|
|
NC46-62
|
158.8
|
71.4
|
9.14or9.45
|
150
|
|
NC46-65
|
165.1
|
57.2
|
9.14or9.45
|
154.8
|
|
NC46-65
|
165.1
|
71.4
|
9.14or9.45
|
154.8
|
|
NC46-67
|
171.4
|
57.2
|
9.14or9.45
|
159.5
|
|
NC50-70
|
177.8
|
57.2
|
9.14or9.45
|
164.7
|
|
NC50-70
|
177.8
|
71.4
|
9.14or9.45
|
164.7
|
|
NC50-72
|
184.2
|
71.4
|
9.14or9.45
|
169.5
|
|
NC56-77
|
196.8
|
71.4
|
9.14or9.45
|
185.3
|
|
NC56-80
|
203.2
|
71.4
|
9.14or9.45
|
190.1
|
|
6-5/8REG
|
209.6
|
71.4
|
9.14or9.45
|
195.6
|
|
NC61-90
|
228.6
|
71.4
|
9.14or9.45
|
212.7
|
|
7-5/8REG
|
241.3
|
76.2
|
9.14or9.45
|
223.8
|
|
NC70-97
|
247.6
|
76.2
|
9.14or9.45
|
232.6
|
|
NC70-100
|
254
|
76.2
|
9.14or9.45
|
237.3
|
|
8-5/8REG
|
279.4
|
76.2
|
9.14or9.45
|
266.7
|
|
NC50-67
|
171.5
|
71.4
|
9.14or9.45
|
159.5
|