Common Well Control Hazards: Identification and Countermeasures

By Xiaozhen Sun

Heavily illustrated with 900 pictures of actual well control sites, Common Well Control Hazards: Identification and Countermeasures provides a visual representation of 177 common well control hazards and how to prevent or counteract them. The perfect companion for any engineer who needs to develop and apply their skill more efficiently, this “plain language guide covers common well control equipment such as: BOP control system, BOP manifold, kill manifold, drilling fluid recovery pipes, IBOP tools, liquid gas separator, and fire, explosion & H2S prevention. With this manual in hand, “new hires not only learn about the inherent hazards which await them out in the field but also gain expert advice for deploying the necessary countermeasures which will lead to effective, incident free field operations.

• Simply describes operational equipment and procedures
• Explains 177 kinds of potential hazards and countermeasure
• Identifies common hazards and their countermeasures

• Language: English
• Publisher: Elsevier Science
• Release date: Dec 13, 2012
• ISBN: 9780123973207

Xiaozhen Sun

Sun Xiaozhen, is the director of Safety and Environmental Protection Supervision Center of Xinjiang Oilfield Company. He is a senior drilling engineer and has been granted with the certificates of national first-class registered safety assessment engineer and national registered safety engineer.

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engineer.

Chapter 1

Common Hidden Dangers and Remedies of Blowout Preventer (BOP) Installation

This chapter describes common hidden dangers and defects of blowout preventer (BOP) installation, and provides remedies for these dangers and defects. These dangers include situations such as installing BOP manual operating rods and fixing the BOP stack, and those involving mud umbrella fences.

Keywords: annular BOP, bent sub, blowout preventer (BOP), chain fall, drawworks, guy line, locking shaft, manual operation rods, mud blocking umbrella, operation platform, pipe-ram BOP, shut in, steamboat ratchet

Common hidden dangers of BOP installation:

• The BOP's side holes face the drawworks.

• The pipe-ram BOP is installed above the blind-ram BOP.

• When the bell nipple tube is installed at the top of the BOP, unused bolt holes are not sealed.

Common hidden dangers of the installation of BOP manual operation rods:

• Manual operation rods are not installed completely for BOPs with a manual locking mechanism.

• Connection between the manual operation rod and the locking shaft is not tightened reliably.

• Manual operation rods and locking shaft are not connected with a cardan joint.

• Obstacles hold back the hand wheel during manual operation rod rotation.

• There is an obstacle that restricts the operation rods or manual wheels.

• Hand wheel operation rods are not connected outside of the derrick substructure.

• The inclination angle between the manual operation rod and center line of the BOP manual locking shaft is greater than 30°.

• There is no operation platform at the manual wheel or the operation platform is higher than the manual wheel.

• The manual wheel operation platform is too small, or there is no mud umbrella or armrest.

• The operation manual wheel has no outer circle.

• The operation rod manual wheel is laid vertically, and the heights of the manual wheels are not unified.

• The manual operation rod near the manual wheel side is not supported firmly, and the freedom is bigger.

• On or off circles are not marked on the hanging tag of the operation wheel.

• There is no counting device when opening or closing the manual wheel.

• After shutting-in manually or locking, the wheel is turned back by a quarter- or half-circle again.

Common hidden dangers for fixing the BOP stack:

• Guy lines for fixing the BOP stack tie up the lower part of the BOP or wind around the BOP body.

• Guy lines are not anchored to the BOP.

• Guy lines are not used with a steamboat ratchet.

• Guy lines use a chain fall.

• The guy line's diameter is less than 16 mm.

• Guy lines are not laid along the diagonal of the derrick substructure.

• Guy lines (props) are tied up by coping bolts, side door bolts, or flange bolts of the BOP.

• Guy lines are fixed upward horizontally.

• Wire rope is used in tying a knot, rope clamps are not used, and rope clamps are stuck reversely or the clamp interval is not up to standard.

• Props are used to fix the BOP stack.

• Wire rope is wound around the BOP flange.

Mud umbrella fence and other common hidden dangers:

• The mud umbrella appears as a horizontal type or umbrella type.

• The mud umbrella area is too small.

• A plastic cloth instead of a mud umbrella is wound around the BOP.

• The square well (cellar) lacks an operation platform.

1 Blowout Preventer Installation

Hidden danger: The BOP's side holes face the drawworks

Hazard

After shutting-in, the kill line passageway is blocked, so there is no way to kill the well operation. In this case, the side holes can be connected to the choke manifold or kill line with pipe, providing a new passageway for killing the well operation.

When the BOP's side holes face the drawworks (Fig. 1-1-3), it is inconvenient to connect pipe from the side holes. Reinforcing ribs of the substructure, relief line, manual locking rod, and so on will all make the stretched out pipe space restricted. Many bent subs need to be connected to the kill line and choke manifold. Otherwise, the space between the BOP and drawworks is narrow, making it inconvenient and unsafe for operators to come in or operate, as shown in Figures 1-1-1 and 1-1-2. In Figure 1-1-4, hydraulic pipe interface of the BOP faces the V-door, and the side hole faces the drawworks.

Fig. 1-1-1 Space between the BOP and drawworks is narrow (A).

Fig. 1-1-2 Space between the BOP and drawworks is narrow (B).

Fig. 1-1-3 Side hole faces the drawworks.

Fig. 1-1-4 Hydraulic pipe interface faces the V-door.

Remedy

When installing the BOP, the side hole of the BOP should face the V-door. Thus, connection has a large operation space, operators are safe, and there is no or little need to use it with bent subs. In this premise, a hydraulic pipe interface should be used, and should face the V-door. The maximum probability of leakage will occur at the hydraulic interface. Perform a daily inspection to observe any leakage, and maintain it in time more conveniently when the interface faces the V-door.

There is a large area in front of and behind the gate of the electric drilling rig. If the BOP side hole faces the V-door, the hydraulic pipe not only can face the V-door, but it can back to the V-door. In a standardization installation, however, the hydraulic pipe should face the V-door. For mechanical drilling rigs, the hydraulic pipe should face the V-door. If the hydraulic pipe interface faces the drawworks, it is difficult to observe the hydraulic pipe interface sealing circumstances behind the BOP. Especially in lower substructure MDRs, no one is willing to get into the BOP back, which is a narrow and dirty passageway that is blocked, to inspect hydraulic pipe sealing circumstances (shown in Figs. 1-1-7, 1-1-8). Roomy space on an electric drilling rig is illustrated in Figures 1-1-5 and 1-1-6.

Fig. 1-1-5 Roomy electrical drilling rig substructure (A).

Fig. 1-1-6 Roomy electric drilling rig substructure (B).

Fig. 1-1-7 Passageway blocked the BOP back.

Fig. 1-1-8 Space of the BOP back is narrow.

The BOP hydraulic pipe interface should face the drawworks, as regulated in SY/T 5964—2006 Standard, however the side hole direction is not regulated.

At present, four methods of laying out side holes and hydraulic pipe interface are available. The recommended installation directions are as follows:

1. For a single side hole BOP where the side hole has no hydraulic pipe, the BOP side hole should face the V-door. The hydraulic pipe interface faces the drawworks, as shown in Figures 1-1-9 and 1-1-10.

2. For a single side hole BOP where the side hole has a hydraulic pipe interface, the side hole and hydraulic pipe should face the V-door, as shown in Figures 1-1-11 and 1-1-12. In Figure 1-1-11, the BOP has hydraulic pipe interfaces on two sides. In Figure 1-1-12, there is a hydraulic pipe interface at only one side of the side hole.

3. For a BOP that has side holes on two sides, its hydraulic pipe interface should face the V-door, as shown in Figure 1-1-13. In Figure 1-1-14, there are all side holes and hydraulic pipe interfaces; therefore any side of the BOP facing the V-door is allowed. Generally, the nameplate faces the