ONGC messes up CBM rig tender for Bokaro block

Vol 19, PW 26 (08 Sep 16) Exploration & Production
     

Somebody in ONGC's tender department looks out of touch with the latest technology used to drill CBM wells.

Drillers have been scratching their heads after reading ONGC's poorly drafted tender to hire a rig to drill CBM wells at its BK-CBM-2001/1 or Bokaro CBM block in Jharkhand, issued on September 2. ONGC wants a 75-tonne mobile drilling rig with integrated mud services for three years.

As is the norm with CBM drilling contracts, payment will be per metre drilled, not a day rate. "Whoever drafted the tender has messed up," says an angry driller.

"The kind of mud-based drilling programme ONGC is proposing was done in the early 1990s, not today." These days, he adds, CBM wells are drilled using air drilling technology. "Reliance, Essar, Dart Energy and even Great Eastern Energy drill CBM wells using rigs with air drilling technology," we hear.

"Mud enters coal cleats within the (coal) seams and reduces well productivity so operators worldwide stopped using mud to drill CBM wells a long time ago." There is also confusion over the type of rig ONGC wants. "A 75-tonne mobile rig is equivalent to 534-hp," we hear.

"But in the tender document, ONGC also says it require 650-hp to drill inclined/horizontal wells." Even more confusingly the tender says that any driller who has operated a 50-tonne workover rig is eligible.

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