Petroleum casing
When it comes to oil and gas well construction, Petroleum casing plays a crucial role in ensuring well integrity and production efficiency. Our high-quality casing pipes are manufactured to meet API 5CT and ISO 11960 standards, providing reliable performance in the most demanding downhole conditions.
Key Specifications of Our Petroleum Casing
- Material Grade: J55, K55, N80, L80, P110, Q125
- Outer Diameter: 4.5" to 20" (114.3 mm to 508 mm)
- Wall Thickness: 0.205" to 1.060" (5.21 mm to 26.92 mm)
- Length Range: R1 (4.88-7.62m), R2 (7.62-10.36m), R3 (10.36-14.63m)
- Connection Types: API BTC, STC, LTC; Premium connections available
- Thread Protection: Plastic or steel caps
- Surface Treatment: Bare, Black, Varnished, or Galvanized
Detailed Technical Parameters
| Grade | Yield Strength (psi) | Tensile Strength (psi) | Hardness (HRC) | Temperature Rating |
|---|---|---|---|---|
| J55/K55 | 55,000 | 75,000 | ≤22 | -50°C to 180°C |
| N80 | 80,000 | 100,000 | ≤25 | -50°C to 250°C |
| L80 | 80,000 | 95,000 | 23-32 | -50°C to 350°C |
| P110 | 110,000 | 125,000 | ≤35 | -50°C to 250°C |
| Q125 | 125,000 | 135,000 | ≤37 | -50°C to 300°C |
Petroleum Casing FAQ
Q: What is the difference between surface casing and production casing in Petroleum casing applications?
A: Surface casing is the first string run in a well, typically set at 500-4,000 ft depth to protect freshwater zones and provide structural support. Production casing is run through the pay zone and serves as the conduit for hydrocarbons to surface. Surface casing is usually larger diameter (13⅜" to 20") with lower grade steel (J55/K55), while production casing is smaller (4½" to 9⅝") with higher grades (P110, Q125) to withstand production pressures.
Q: How do I select the appropriate Petroleum casing weight for my well?
A: Casing weight selection depends on several factors: well depth, formation pressures, corrosive environment, and completion design. Shallow wells (≤5,000 ft) typically use 17-20 lb/ft casing, intermediate wells (5,000-10,000 ft) use 23-26 lb/ft, while deep wells (10,000-15,000 ft) require 29-32 lb/ft. Our engineers can perform detailed casing design calculations considering burst, collapse, and tensile loads specific to your well conditions.
Q: What maintenance is required for Petroleum casing during well operation?
A: Proper casing maintenance includes: regular pressure testing (annually or after workovers), corrosion monitoring through caliper surveys or corrosion logs, chemical inhibition programs for CO2/H2S environments, and avoiding excessive bending or shock loads during workovers. For thermal wells, consider expansion joints to accommodate thermal cycling. API RP 90 provides detailed casing integrity management guidelines.
Specialty Petroleum Casing Products
- Corrosion Resistant Alloy (CRA) Casing: 13Cr, Duplex, Super Duplex, and Nickel alloys for severe service
- Expandable Casing: Up to 20% diameter expansion capability
- Thermal Casing: Special grades for steam injection and SAGD applications
- High Collapse Casing: Enhanced collapse resistance for deepwater wells
- Lined Casing: Carbon steel with internal plastic or corrosion-resistant lining
Quality Assurance
Our Petroleum casing undergoes rigorous quality control:
| Test | Standard | Frequency |
|---|---|---|
| Hydrostatic Test | API 5CT §7.8 | 100% |
| Ultrasonic Inspection | API 5CT §7.10 | 100% |
| Hardness Test | API 5CT §7.9 | 5 per heat |
| Charpy Impact Test | ASTM A370 | 3 per heat |
| Full-length Inspection | API 5CT §7.7 | 100% |
With over two decades of experience in Petroleum casing manufacturing, we provide technical support from casing design through installation. Contact our engineering team for your project-specific requirements.