Petronas Selects DRAG® Technology Again

For the second time in recent months (see the Summer 2000 issue of Solutions), Petronas has ordered additional CCI control valves for its ANGSI-A offshore platform, part of a large oil-gas project in Malaysia. The previous order included anti-surge control valves for the large HP and LP compressors for gas re-injection.

The current order includes two 12 inch (300 millimeter) valves for second-stage compressor discharge service, a six inch (150 millimeter) valve for water-injection control, and four four inch (100 millimeter) valves to control minimum flow.

The 12 inch (300 millimeter) second- stage compressor discharge control valves handle up to 631 pounds/hour (286,000 kilograms/hour) of gas at pressures upto 2000 psig (138 BarG). To limit sound-power levels to less than 85 dBA, trim exit velocity head (Hv =rV2/2g) islimited to 70 psi (4.8 Bar) at three feet (1 meter).

In the four and six inch (100 and 150 millimeter) injection and minimum-flow control valves where flows up to 425,000 pounds/hour (193,000 kilograms/hour) with DPs as high as 2000 psi (139Bar), trim-exit fluid velocities are held to less than 100 FPS (30 meters/second), again to hold noise below 85 dBA at three feet (one meter) tocontrol noise and eliminate the damaging effects of vibration.

In all cases, these valves provide a 10 percent over-capacity margin. Top revent flow-induced plug vibration, multi-stage disk-stack trim incorporates pressure-equalizing rings (PERs) to assure equal pressures around the plug. All noise levels cited are based on no thermal acoustic padding on the downstream piping.

Published in SOLUTIONS Winter 2000