Flapper-Type Float Valve: Essential Backflow Prevention for Drilling Operations
The Backflow Contamination Challenge
During pipe connections, uncontrolled backflow causes:
-Bit nozzle plugging with cuttings → 4-8 hours NPT per incident
-Drill string corrosion from abrasive sediment ingress
-Well control risks from underground blowouts during connections
Our flapper-type float valve delivers:
✅ Instant 2-second closure upon pump stoppage
✅ 10,000psi wellbore pressure sealing capability
✅ API 7-1 certification for reliable performance
How It Works: Automatic Flow Control
Dual-Function Protection System
Operation Mode | Mechanical Action | Result |
Normal Drilling | Flapper held open by flow pressure | Continuous circulation |
Pump Stoppage | Flapper instantly closes via spring & differential pressure | Prevents backflow |
Kick/Blowout | Well pressure forces flapper into sealed position | Contains pressure in string |
→ Spring-assisted closure for instant shutoff
→ Pressure-balanced design prevents premature closing
Technical Specifications
Parameter | Specification |
Pressure Rating | 5,000psi & 10,000psi options |
Closure Time | <2 seconds from flow reversal |
Temperature Rating | -50°C to 175°C |
Material Grades | 4140 steel, 410/420 stainless, alloy 625 |
Connections | API REG, IF, FH (all standard sizes) |
Compliance | API Spec 7-1, API RP 59, NACE MR0175 |
Operational Benefits
✅ Eliminate Nozzle Plugging
Zero backflow during connections → save 16 rig hours/well
Reduced bit trips from plugged nozzles
✅ Enhanced Well Control
Secondary barrier during kicks
Contains pressure inside drill string
✅ Extended Tool Life
Hard-coated flapper resists erosion
Replaceable seal rings for multiple runs
Field Applications
Deepwater Drilling: 10,000psi rating for HPHT wells
Slimhole Operations: Compact design for 3-1/2" strings
Underbalanced Drilling: Prevents gas influx up string
Geothermal Wells: High-temp elastomers for 175°C service
