There are three basic types of rotary bottomhole assemblies used in directional drilling: Building Assemblies, Dropping Assemblies, and Holding Assemblies. A building assembly is intended to increase hole inclination, a dropping assembly is intended to decrease hole inclination, and a holding assembly is intended to maintain hole inclination. It should be noted that a building assembly might not always build angle. Formation tendencies may cause the assembly to drop or hold angle.
USA1 - Casing bottom hole assembly retrieval process - Google Patents
A bottom hole assembly BHA is a component of a drilling rig. It is the lowest part of the drill string , extending from the bit to the drill pipe. The assembly can consist of drill collars, subs such as stabilizers, reamers, shocks, hole-openers, and the bit sub and bit. Rotary assemblies [2] are commonly used where formations are predictable and the rig economics are an issue.
Because all packed assemblies will bend to some extent, however small the amount of deflection, it is not possible to make a perfectly vertical hole. The rate of hole angle change may be kept to a minimum for normal deviation but occasionally conditions will arise where the total hole deviation must be restricted to closer tolerances. When this condition occurs the pendulum technique is employed, however if it is anticipated that a packed hole assembly will be required after reduction of the hole angle, the packed pendulum technique is recommended. The pendulum assembly is based on the principle that the only force available to straighten a deviated hole is the weight of the drill collars between the point of tangency stabiliser and the bit.
The Bottom Hole Assembly BHA is a key component of the drilling system, consisting of various components and tools including the drill bit itself which operate at the bottom of the wellbore and physically drill the rock. The BHA is connected to the drilling rig by the drill pipe, an extendable hollow tube which conveys the mechanical and hydraulic energy and movement from the surface rig systems to the bottom hole assembly. This complex arrangement of tools varies considerably depending on requirements, and can stack up to 1, ft long. The BHA has become more complex over time to suit the needs of drilling operations and to accommodate different tools that have been developed.
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came so fucking hard on this one you are perfect
I WOULD LOVE TO HELP YOU TAKING CARE OF THOSE SWEET AMAZING TITS!
wow your legs!
Austin Powers chick love it
would love to kneel behind you
i want to pput my strap on in you:)
love those tits,jus wanna slide this hard dick btween them until i cum.
can you play whit me in skype or msn?
mmmm bby
lmao. niggas be thinkin the actual girls posted this.
Normal sex
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That's good view
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