Perforated Casing is manufactured by the most advanced equipment, 72 hole automatic drilling lathe. It is used to obtain production from sandy or caved oil-bearing formations. Each Perforated Casing made by Aokai is deburred and drift tested to conform to API standards, and each opening is clean cut and visually inspected and deburred.
| Pipe Size | Holes per feet | Size of hole | Perforated Area per Feet |
| 3/4" | 78 | 3/16" | 2.15 |
| 1" | 54 | 5/16" | 4.14 |
| 1-1/4" | 66 | 5/16" | 5.06 |
| 1-1/2" | 78 | 5/16" | 5.98 |
| 2-1/16" | 78 | 5/16" | 5.98 |
| 2-3/8" | 90 | 3/8" | 9.94 |
| 2-7/8" | 102 | 3/8" | 11.26 |
| 3-1/2" | 126 | 3/8" | 13.91 |
| 4" | 138 | 3/8" | 15.24 |
| 4-1/2" | 150 | 3/8" | 16.56 |
| 5" | 162 | 3/8" | 17.88 |
| 5-1/2" | 174 | 3/8" | 19.21 |
| 6-5/8" | 186 | 3/8" | 20.53 |
| 7" | 222 | 3/8" | 24.51 |
| 9-5/8" | 294 | 3/8" | 32.46 |
