LA Aluminum was able to cast-in steel nut inserts that eliminated the secondary drilling
and tapping operation.
Outside of new and secondary drilling
projects, EPL will spend about $61.2 million on intervention work at existing wells and on water flooding, a technique that injects hot water into a reservoir to reduce oil viscosity allowing it to flow more easily toward a production well.
Minor oil shows were observed in the Birkhead Formation, a secondary drilling
According to Haasbroek, even with the tighter pattern, many of the boulders remain intact and require secondary drilling
. Also, because of persistent groundwater flows in the active mining areas, holes occasionally collapse and consequently, redrilling requirements can vary from around 9% during the dry season to as much as 40% during the rainy season.
And a secondary drilling
operation is needed to open vacuum channels.
Until 1991 or 1992, Lincoln Brass turned out valves and fittings primarily on screw machines and a battery of other machines for secondary drilling
, milling, threading, finishing, and so on.
Ozdemir explained that the circular-shaped opening created by TBMs is usually not suitable for mine operations, but this problem can be solved by backfilling behind the machine to create a flat floor, secondary drilling
and blasting after excavation to create a more suitable cross-section, or by mounting a set of boom cutters on the sides of the TBM to create a horshoe-shaped entry.