Bolt Cover Type Shaffer Annular BOP 9" Bore 5000psi Forging Blowout Preventer System

The Shaffer Bolt-Cover Spherical BOP is a high-reliability annular pressure control equipment which is designed for oil and gas drilling operations. As a key well control equipment, it delivers stable sealing and pressure control during drilling, tripping, and well intervention processes, mitigating blowout risks effectively to protect person safety, equipment, and the environment.

• Well Pressure Containment: Acts as a frontline defense against unexpected wellbore pressure surges, forming a tight seal to prevent blowouts.
• Universal Sealing Compatibility: Seals reliably on various downhole tools and components, including kellys, drill pipes, tool joints, drill collars, casing, and wireline tools.
• Pressurized Tripping Operations: Enables safe tripping of drill strings in and out of the wellbore under pressure, withstanding the wear of dynamic operations.
• Harsh Environment Adaptability: Suitable for internal H₂S service as standard, with straightforward conversion for external H₂S service; Arctic models are available to meet low-temperature API 16A requirements.

1. Compact & Space-Saving Design

   Height is 15 to 20% lower than comparable annular BOPs, ideal for installations with limited vertical space.

   Simplified structure reduces overall footprint without compromising performance.

2. Efficient & Cost-Effective Operation

   Operates at a low hydraulic pressure of 1,500 psi, reducing the required accumulator size and associated costs.

   Minimal hydraulic connections (only two for opening and closing) simplify system integration.

3. Durable & Low-Maintenance

   Wear rings on moving parts eliminate metal-to-metal contact, extending component service life.

   Wiper seals and wide clearances prevent debris accumulation and accelerate wear.

   Rugged sealing element with steel reinforcement maintains reliable performance for 2–4 times longer than conventional elements, reducing replacement frequency.

4. Easy Servicing & Field Adaptability

   Upper housing lifts off easily for access to internal components; adapter ring shields hydraulic systems from mud and grit during maintenance.

   No complex tools required for routine servicing, minimizing downtime.

1. Basic Closure & Opening

   Closing: Apply hydraulic pressure (max 1,500 psi) to actuate the piston, driving the sealing element in a smooth upward and inward motion to seal the wellbore.

   Opening: Release closing pressure and apply opening hydraulic pressure to retract the piston, allowing the sealing element to return to its open position automatically.

2. Stripping Operations (Step-by-Step)

   Close the BOP with a maximum of 1,500 psi hydraulic pressure.

   Prior to stripping, reduce closing pressure to allow a slight leak (for lubrication and temperature control).

   Maintain slight leakage if conditions permit; gradually increase pressure as the element wears to control excess leakage.

   If leakage is prohibited, set pressure just enough to maintain a tight seal.

   Switch to an alternate preventer when required closing pressure approaches 1,500 psi to avoid overwearing the element.

3. Safety & Operational Notes

   Ensure the BOP is rated for the well’s working pressure and fluid conditions (e.g., H₂S service).

   Regularly inspect the sealing element for wear; replace if leakage exceeds acceptable limits or after prolonged stripping.

   Comply with API 16A (Forth Edition, 2017) and NACE MR0175 standards for operation and maintenance.

   Use oil (not grease) on the piston and cylinder during reassembly to ensure smooth movement.

Bore Sizes: 4 ½ inches to 30 inches (varies by model).

Working Pressure Ratings: 1,000 psi, 2,000 psi, 3,000 psi, 5,000 psi, and 10,000 psi.

Temperature Range: Standard models (nitrile element): 40°F to 180°F (4°C to 82°C); low-temperature Arctic models available.

Sealing Element Options: Nitrile (blue) and natural rubber (red) for different service conditions.