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The DAPC System - Automated Choke Manifold

The DAPC choke manifold meets API 6A specifications and ATEX standards. It is rated for 5,000 psi (345 bar) maximum working pressure, 7,500 psi (517 bar) max test pressure, and H2S operations. (Click image to enlarge)

Constant Bottomhole Pressure
Constant bottomhole pressure is about saving time and money spent fighting through narrow pressure margins, eliminating lost circulation and stuck pipe, controlling influx, stabilizing the well, and drilling difficult to reach targets. The most consistant way to overcome these challenges is with around the clock automated control.

The automated choke manifold utilizes new choke technology to manage backpressure precisely and fast during connections and while drilling with pipe, coiled tubing, or liner.

The Choke Manifold

The DAPC employs a suite of automated pressure control equipment to maintain constant bottomhole pressure - one of them is the choke manifold.

The DAPC choke manifold makes the immediate adjustments to the backpressure under the control of the Integrated Pressure Manager (IPM) to which it is linked by a high speed network connection.

Using pressure instruments installed on the choke manifold the IPM monitors the backpressure and maintains it at the level calculated by the hydraulics model. If it detects an imbalance in the pressure the IPM issues a command to the manifold which instantly responds by immediately adjusting the choke.

By utilizing the manifold’s ability to switch between redundant main chokes and separately provide automated pressure relief the IPM can respond to a wide range of contingencies.

Failsafe features designed into the manifold enable it to automatically switch from one main choke to another (manifold drawing) if the active choke opens or closes beyond the programmed position. If the IPM detects such a condition it directs the manifold to switch to the backup choke and isolate the other to stabilize the BHP.

In the event communication between the pressure manager and the manifold is disrupted then the system maintains the choke as is to maintain a stable backpressure. The system automatically issues an alert to the Control System Operator that it has switched to manual mode.

Continuous Flow

An important capability of the manifold is its ability to maintain continuous mud flow. One feature that suports this capability is its large ID piping, redundant choke legs, and automated switching in the event of a jam.

Choke plugging is minimized through the use of 4-1/16" chokes which have the largest available internal orifice (3.0"). Also, if debris plugs the active choke, the pressure manager will automatically increase its opening to relieve the pressure and clear the debris.

If the choke reaches the full-open position and pressure is still unrelieved then the pressure manager will automatically switch to the backup choke and alert the operator.

Our mainfolds can be configured with an auxiliary third choke that it can operate as either the primary pressure relief valve (PRV) or a backup PRV, all while continuously controlling backpressure through the active main choke.

The system's ability to smoothly control pressure eliminates the sudden and potentially damaging pressure spikes that can be caused by standard PRVs that operate in an all open-or-all closed manner.

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