Crossover sub is mainly used to connect upper and lower drill tools into different connectors in drilling operations. Also, it can be used to protect other tooling in the drill stem (called saver sub) or be used to deliver outgoing air to the bit face just above the bit (called bit sub).
The length of crossover subs is generally measured from shoulder to shoulder. Typical lengths range from 6" - 28" long going up in increments of 2 inches with AISI 4145H, AISI 4145H Mod, AISI 4340, AISI 4140-4142 and Non-magnetic material. All connections are phosphate-coated or copper-plated to improve resistance to corrosion. Crossover subs come in three basic types: A Pin (male) * Box (female); B Pin (male) * Pin (male); C Box (female) * Box (female)
| Crossover sub | |||
| Description | UpperConnection part | Lower Connection Part | Type |
| Kelly cross-over sub | Kelly | Drill pipe | A or B |
| Drill pipe cross-over sub | Drill pipe | Drill pipe | A or B |
| Interim cross-over sub | Drill pipe | Drill collar | A or B |
| Drill collar cross-over sub | Drill collar | Drill collar | A or B |
| Drill bit cross-over sub | Drill collar | Drill bit | A or B |
| Swivel cross-over sub | Swivel lower sub | Kelly | C |
| Fishing cross-over sub | Kelly | Drill pipe | C |
| Drill pipe | Fishing tools | C | |
| Our Crossover sub can be customized as per customer's design | |||