METAL MUNCHER AMT drilled out Inconel 718 packer with zero NPT
A Norwegian operator in a North Sea field needed to retrieve a 9 ⅝-in. Inconel 718 packer, but did not think it was possible to mill the packer because of its strong, nickel alloy construction. A fishing services team from Baker Hughes, a GE company (BHGE), took on the challenge of milling the packer, and recommended using a specially made packer mill dressed with METAL MUNCHER™ advanced milling technology (AMT) carbide P-7, the industry’s most durable, effective cutting and swarf control cutting structures.
The METAL MUNCHER AMT P-7 inserts were chosen because Inconel 718 material, a hard, high-temperature-withstanding, corrosion-resistant, nickel-based alloy, was used in the manufacture of the packer to be milled. The METAL MUNCHER inserts were engineered using pressed and sintered tungsten carbide to incorporate a durable technology that increases milling penetration rates, extends effective time-on-bottom in high volume milling applications, and enables greater flexibility during the milling process.
BHGE deployed the 8 ½-in. packer mill with AMT to mill the packer located at 8837.5 ft (2693.7 m). Milling started out with good parameters, and then progress slowly waned. Rotation was decreased from 80 to 60 rpm and the milling progress improved at this lower rpm and with high weight on mill. After milling 6.5 ft (2 m), the packer appeared to be spinning. The pumps were shut off and burning went on for 10 minutes, after which a sudden drop was observed. Circulation was reestablished and the milling operation resumed.
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