8/7/2019 Directional_drilling_equations

1/3

DIRECTIONAL & HORIZONTAL DRILLING EQUATIONS

TRIANGLES:

Sin = Opp Cos = Adj Tan = Opp Hyp = Opp Hyp = Adj

Hyp Hyp Adj Sin Cos

Opp = Sin x Hyp Adj = Cos x Hyp

CIRCLES:

Curvature or BUR = 5730 RC = 5730

RC BUR

TVD = RC x (Sin INC2 Sin INC1) VS = RC x (Cos INC1 Cos INC2)

MD = RC x 2 x Pi x (INC2 INC1) = RC x (INC2-INC1)

360 57.3

VBURREQ = 5730 x Sin Target INC Sin Current IncTarget TVD Current TVD

VBUR = 100 x (INC2 INC1) VBURACTUAL = (Cos TFO) x DLTOTALMD2 MD1

TVDDIP = Vertical Section x (Tan 90 + Dip)

PBIT = MW x (GPM)2 TFANOZZLES = MW x (GPM)2

10859 (TFA)2 10859 (Pbit)

HHP = Pbit x GPM HSI = HHP AREAHole = 0.7854 (Dia)21714 Area Hole

DoglegOreinted = 200 x Bit TiltLength of Bit to Top Stabilizer

Angle Change = BUR x CL CL = Angle Change x 100

100 BUR

BUR / 100 = Change In Angle x 100 DLS / FT = Angle Change

CL CL

8/7/2019 Directional_drilling_equations

2/3

Projected TVD @ Bit = RC x(Sin INC2 Sin INC1) + Existing TVD

BUR Needed to Target = (Sin Desired Angle Sin Present Angle) x

5730______________

(Target TVD Current TVD)

DLS / 100 = (Cos last INC x Cos new INC) + (Sin last INC x Sin new INC) x

Cos Directional Difference = Cos-1 x 100

CL

Projected Angle Needed to Reach Target = Target TVD Present TVD =

Arc Tangent of Angle. Usable VS

Add to 90 deg. if Angle is over 90 deg. Subtract if Angle is under 90 deg.

Usable VS = Target VS Present VS

Projected BUR From TF Setting = BUR = Cos Avg. TF x DL

Projected MD = Target INC Last INC

DLS/Ft

To Find CL When You Know BUR & Angle Needed = Angle Needed

BUR = CL

100

To Find

BUR When You Know The TVD, INC1 & INC2 = 5730 / _ TVD (usable)____

Sin INC2 Sin INC1

CL Angle = Divide by N or S to Get Tangent of Angle (Inv. Tangent-1)

CL Distance = Take CL Angle if over 45 deg Find Sin of Angle & Divide it into the

Largest Coordinate to get Distance. If Angle is Below 45 deg Use Cos of Angle &

Divide it into the Largest Coordinate.

TF Setting = Angle Change Arc Cos CL Distance = (NS)2 + (EW)2

DLS

Formation Dip in Feet = Tangent of Formation Dip x VS

Bit Angle Projection = Take BUR of Last Survey x CL Divide by 100 = Angle

change. Add Angle Change to Last Survey.

Bit Direction Projection = Take the Difference of Last 2 Surveys Divide by CL of

Last Survey = Direction Change per Foot x Projected CL. Then Add or Subtract

From Last Survey Direction.

8/7/2019 Directional_drilling_equations

3/3