Innovative logging technique boosts productivity for Chevron Thailand

Posted on 24 November 2009

chevronUnder rig floor logging (URFL) is a technique pioneered by Chevron Thailand that has improved drilling efficiency by moving logging operations away from the drilling path, allowing wireline and drilling operations to be performed simultaneously.

This innovative technique to increase drilling productivity was presented at the IADC Well Control Asia Pacific 2009 Conference & Exhibition by Thaveesub Laoamornpanich, drilling engineer for Chevron Thailand.

“There are a number of conditions required for under rig floor logging,” Mr Laoamornpanich said. “The first is batch drilling. In Thailand, Chevron usually typically drills wells in eight- or 12-well batches.” Chevron has used URFL from 10 platforms, as well as three tender assist rigs and two jackup rigs, with both open and cased hole.

Other conditions required include predictable hole stability and a predictable well control environment.

“We also need a mind-set that repeatability and process standardization are possible both on the rig and in the office,” he added.

Benefits of this approach include less rig time to drill a well and less rushing to pick the tubing X-nipple locations in each well after the log is obtained. Also, a wireline tool problem has less impact on the overall operation, and extra wireline logs may be run with no impact on rig time.

Mr Laoamornpanich estimated that from June 2007 to July 2009, Chevron Thailand saved more than 40 rig days by employing URFL on 76 open-hole wells and 31 cased-hole wells.

Once a well is drilled, URFL is accomplished by skidding the rig over to next well location and starting logging operations on the previously drilled well. Key components for open holes include a pressure control and riser system, a hydraulic control system for well control equipment, work platforms to access these valves, and a trip tank.

In normal URFL operations, the wireline unit is placed on a URFL cantilever on the BOP deck beneath the rig floor. Wireline is first run laterally through a diverter sheave and then over an A-frame swivel sheave down into the wellbore.

In the event of well control concerns in open-hole logging, Mr Laoamornpanich said, wireline from the URFL cantilever is rerouted from the URFL cantilever up to the rig floor, tubing is then run downhole.

Chevron uses 22 criteria for making a “Go/No Go” decision on whether to use URFL. Key considerations include barite sag, mud properties, kick tolerance, swab gas, hole condition, well control incidents and weather.

Typical response to a well control event involves immediately shutting down the unaffected operation. If the wireline operation is affected by a well control event, the rig is then skidded back to the previous well.

Though originally designed for Chevron’s fast-paced drilling operations in Thailand, the URFL concept is currently being adapted for use in Chevron’s Nigeria operations.

0 Comments For This Post

1 Trackbacks For This Post

  1. WellCAP plays key role in fast-paced Thailand drilling operations | Drilling Contractor Says:

    [...] Other special situations included in the company’s WellCAP courses include slim-hole drilling and special monitoring, equipment and procedures for under rig floor logging (see article here). [...]

Leave a Reply

*

FEATURED MICROSITES


Recent Drilling News

  • 01 August 2014

    Fugro’s real-time helideck monitoring aids operational planning, safety

    Fugro has developed and delivered a new fully integrated helideck monitoring system to Diamond Offshore’s Ocean Guardian in the North Sea. Severe...

  • 31 July 2014

    Eni discovers gas and condensates offshore Gabon

    Eni has made a gas and condensates discovery in the Nyonie Deep exploration prospect in block D4, approximately 13 km offshore Gabon and 50 km from the capital city Libreville...

  • 31 July 2014

    Blue Ocean Technologies: Subsea well intervention completed in 6,700- ft record depth

    Blue Ocean Technologies has set multiple records in subsea well intervention by intervening in, and subsequently plugging and abandoning, a production gas...

  • 30 July 2014

    Fugro’s DeepData pod provides data for deepwater riser monitoring

    Fugro has delivered a motion dataset from the BOP stack and lower riser of two deepwater wells in the Barents Sea using its DeepData pods. The DeepData pods...

  • 28 July 2014

    SDI completes 500th MagTraC MWD Ranging project

    Scientific Drilling International (SDI) has completed the 500th MagTraC MWD Ranging project. MagTraC was introduced in 1998 to target challenging applications...

  • Read more news