PCEBlowOut Preventer

Description

PCE Blowout Preventer (BOP)

Technical Description

A BOP uses hydraulically or mechanically actuated rams to seal the wellbore. These rams are equipped with specialized inner rubbers that have a semi-circular groove precisely sized to the slickline wire. When closed, the rams meet in the center, squeezing the rubber around the wire to create a gas-tight seal without crushing or “kinking” the metal line.

RAM Configurations: Single, Double, and Triple

The choice of BOP depends on the complexity of the operation and the level of safety redundancy required by the well’s pressure profile.

1. Single RAM BOP

• Design: Features one set of sealing rams.

• Function: Used primarily for low-pressure, “sweet” wells. It provides a basic shut-in capability if surface equipment needs repair or if the stuffing box packings fail.

2. Double RAM BOP

• Design: Features two sets of rams in a single body.

• Function: Usually configured with one set of Wire Rams (to seal around the wire) and one set of Blind Rams (to seal the well completely if the wire is not in the hole).

• Inversion Use: In some cases, the bottom rams are inverted to allow for Grease Injection between the two ram sets, creating a higher-integrity “liquid seal” for high-pressure gas.

   

3. Triple RAM BOP

• Design: Features three sets of rams.

• Function: The gold standard for high-pressure/high-risk wells.

  • Top Rams: Seal around the wire.

  • Middle Rams: Often inverted for grease/chemical injection.

  • Bottom Rams: Act as a final safety backup or Blind Rams.

• Advantage: Provides maximum redundancy and allows for “equalizing” pressure across the rams more effectively during complex fishing operations.

Key Technical Specifications

• Seal Integrity: Rams are “sized” specifically for the wire diameter (e.g., 0.092″, 0.108″, 0.125″). Using the wrong size ram rubber will result in a leak or wire damage.

• Equalizing Valves: Every BOP features internal or external equalizing valves.⁵ These allow the operator to balance the pressure above and below the rams before opening them, preventing the BHA from “shooting” up into the lubricator.

• Manual Locking: Even hydraulic BOPs feature manual “locking wheels.” Once the rams are closed hydraulically, they are mechanically locked to ensure the seal holds even if hydraulic pressure is lost.

Critical Parameters