DRAG® technology for severe service choke valves
CCI can help you increase choke life and production uptime and improve safety – and reduce your stocks of spares, maintenance costs and start-up problems.
Today’s gas field environment is characterised by high wellhead pressures with aggressive fluids and entrained sand and other solids. A conventional single stage choke valve is not suitable for this kind of severe service. You need to maintain production rates. Repairing or replacing chokes frequently is no longer an option. The answer – the world’s first true severe service choke valve, from CCI.
We’ve been solving severe service control valve problems in the oil & gas industry for over 30 years. The CCI severe service choke combines proven DRAG® velocity control technology with the best grades of tungsten carbide. The result: long trim life and precise process control.
Fluid velocity is the main cause of erosion. Erosion rates will vary as a third-to-fifth power function of velocity (V3 to V5). Example: erosion will be reduced by a factor of between 8 and 32 if the velocity can be reduced by a factor of 2.
The DRAG® valve concept
CCI’s DRAG® disk stack controls flowing velocities throughout valve trim by forcing the process fluid to follow a tortuous path of right-angle turns. The resistance to flow provided by these turns (or stages) limits the trim exit velocity to a safe level, regardless of the pressure drop.
The DRAG® choke valve eliminates problems resulting from excessive fluid velocities – erosion of trim and body, noise, vibration, poor process control. Fluid velocities within the trim of CCI choke are typically one-third to one-quarter those of conventional single stage chokes. Velocity control protects the trim from erosion and increases the trim life many times.
We spent several years developing the manufacturing and design technology to make solid tungsten carbide DRAG® disk stacks. As a result, we can now make all stages from hard, erosion-resistant tungsten carbide.