The cementing plug is used to separate the cement slurry from the mud. It can prevent the mud from blending into the cement slurry to influece the cementing quality.
Structure:
There are two kinds of cementing plug: conventional cementing plug and special cementing plug. Conventional cementing plug is divided into top plug and bottom plug. Special plug has top/middle/bottom plug used in two-stage cementing, drill pipe plug and hollow plug used in drilling liner cementing and composite plug used in composite casing.
Structure features:
1.The top plug is solid. The bottom plug is hollow. They can all be drilled out with PDC bits.
2.The material of the plug body is acrylonitrile- butadiene rubber. It is heat-resisting and tough.
3.Special materials designed for easy drill out with PDC bits
4. Normal and non-rotating type can be available
5. The non-rotating type can save the drilling time
6. Size: 4 1/2"--20":
Specification:
| Casing size(in) | casing weight range | Wiper Fin O.D | ||
| mm | in | mm | in | |
| 4 1/2" | 14.14-17.26 | 9.50-11.60 | 110 | 4.331 |
| 5" | 17.11-35.86 | 11.50-24.10 | 122 | 4.803 |
| 5 1/2" | 20.83-39.88 | 14.00-26.80 | 135 | 5.315 |
| 7" | 25.30-56.55 | 17.00-38.00 | 170 | 6.693 |
| 7 5/8" | 35.72-63.69 | 24.00-42.00 | 185 | 7.283 |
| 9 5/8" | 53.57-79.62 | 36.00-53.50 | 235 | 9.252 |
| 10 3/4" | 60.27-97.77 | 40.50-65.70 | 260 | 10.236 |
| 13 3/8" | 71.43-107.15 | 48.00-72.00 | 333 | 13.110 |
| 20" | 139.89-197.93 | 94.00-133.00 | 498 | 19.606 |
