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

  • 03 March 2015

    Kosmos Energy finds hydrocarbons in CB-1 exploration well offshore Western Sahara

    Kosmos Energy announced that the CB-1 exploration well located in the Cap Boujdour permit area offshore Western Sahara encountered hydrocarbons. The well penetrated...

  • 02 March 2015

    Maersk Voyager drillship secures contract for work offshore Ghana

    Maersk Drilling has been awarded a contract from Eni Ghana Exploration and Production, an Eni subsidiary, for employment of the newbuild drillship Maersk Voyager...

  • 02 March 2015

    Wisco Moran debuts Padwise 1 walking rig in Texas

    The trend among drilling contractors to install walking systems on rigs has solved a major logistical problem for operators on multiwell pads – negating the need for costly...

  • 26 February 2015

    JDC inaugurates Hakuryu 12 jackup, looks to growth in Middle East, Myanmar and Russia

    The Japanese word “hakuryu” means “white dragon.” In Asia, dragons are strongly associated with oceans. They also represent power and blessings...

  • 16 February 2015

    Steven Newman steps down as Transocean President, CEO

    Transocean announced that Steven Newman and the Board of Directors have mutually agreed that he will step down as President and CEO, effective 16 February 2015...

  • Read more news