Innomag® string magnets recovers 40 kg of steel from milling job
One 12,1” OD Innomag® string magnet alone caught 9,6 kg steel cuttings, proves capacity
Challenge
- Milling casing window generates large amount of steel cuttings
- Steel cuttings circulated to surface plugs up flowlines, damage mud pumps and cause problems
Solution
- Mobilized 4 Innomag® string magnets with standard section milling package
- Installed string magnets above casing mill in BHA
Benefit
- Recovered steel cuttings downhole
- Prevented cuttings to reach surface and cause problems
- Now standard routine when milling casing
Project
The client drilled an exploration well from a semi-submersible rig at the Haltenbanken area in Norway. After an initial discovery in the first vertical wellbore, a requirement arose from the license partners to drill a geological sidetrack to appraise the discovery further. A long reach target required a kick off from inside the 13 3/8” casing high up in the well.
Drilling operation
The operator decided to plug the vertical wellbore permanently with balanced cement plugs. A cement plug was set across the 13 3/8” casing shoe, and the crew ran in hole with a casing milling assembly. A casing window was milled above the top of hard cement, and the well was successfully kicked off with a rotary steerable BHA.
Circulation while milling
The drill crew took precautions before the milling, in order to protect the flowlines, shakers and mud pumps from steel cuttings. A new effective MFF® (Magnetic Mud Filter) was installed in the flowline. However, very small amounts of fine steel particles were recovered on the surface, as most of the steel cuttings was recovered downhole on the Innomag® string magnets.
Benefits
The use of effective magnets downhole and on surface prevented plugged flowlines, damage to shakers & mud pumps, and general contamination of steel particles in the BOP and surface mud circulation systems. This reduced the risk for lost time and money for the operator, and expensive equipment damage for the drilling contractor.
“The use of string magnets in our casing milling assemblies is now part of our standard operating procedure.”
Questions about this job?
Tell us what is stuck in your well and we will tell you what we can do.
