IWCF Formula Sheets

IMPORTANT FORMULAE FIELD UNITS - US IMPERIAL Nydrostatic Pressure

tll

HSP

Depth

6,i;: Mud Density $pe) x 0.052 (rb.gar/sqin/tt) x True Vertical

Pressure Gradient

:

Mud DensitY

x 0.052

l2]

Mud or Pressure Gradient

i3]

Formation Fracture Gradient (psi/rr;: Maximum Aliowable Mud DensitYoper x 0.052

[4]

Influx Gradient gsi/ft): Mud Gradient

1p*vrtl

@si/ft)

rppgr

- ((SICP - SmPP) / True Vertieal Influx Height G))

Mud Density

t5l

Mud Densif opet: Pressure 6,i; / 0.052 / TVD

t6]

Mud Density tppgl: Pressure Gradient

l7l

Kill Mud Density

bsi/rt)

1ny

I 0.052

(ppg): SIDPP I 0.052 / TVD ttl + OMD

,oor,

Trwe Vertical Depth

[8]

TVD (ft): HSP

t9]

TVD (ft): Cosine Deviatioil ldegrees) x Measured Lenglh 1ty

t10l

Influx Length in hole

tpsil

/ 0.052 / Mud Density

(ft)

:

1oorl

Pit Gain o6) / Annular Capacity

t11l True Vertical Influx Heightlry:

Cosine Deviation

UNSW

Document No.

School of Petroleum Engineering Svdnev NSW 2052

NDWCP.QA-FSAPI

(degrees)

Revision No. 6 Date: 27-Jan-2006

lurvn;

x Influx Length

Formula Sheet API

lrty

Page

I of5

1ri;

IMPORTANT FORMULAE FIELD TINiTS - US IMPERIAL Maximum Allowable Mud Density & Equivalent Circulating Density

-

Ll2l

MAMD

[13]

MA.MD (ppe): Total Pressures @ Shoe 1p,iy / 0.052 i TVD of Shoe

t14]

ECD loog;: Annular Friction Loss 1p,iy I A.A52 / TVD rtr + OMD

(pps)

Leak-off Pressure rpsr / 0.052 / TVD of Shoe 1ri * Test Fluid Density 6o*y 1r1

1oor,

Msximam Allowable Arunular Surface Pressure

[15]

MAASP tpsr: (MAMD

roo*r-

Current Density6oe) x 0.052 x Shoe TVD

rnl

Formation Fressure

[16]

Formation Pressure

(p,i)

:

HSP 1p"i1+ SIDPP

[17]

Formation Pressure

(psi)

:

Pore Pressure Gradieflt

Y o Ia

rn e o C ap a c ity,

D isp lac em e nt,

1p,iy

lpsi/ft)

x TVD

O utp u t, V e I o c ity

t18] Volume $br): Capacity Gbvft) x Lenglh

1ny

I

t19]

Pipe or Hole Capacity iurvny: ID2

t20]

Annular Capacity

l2l)

Pipe Displacement 6brig;: @ipe OD21;n"r,,".; - Pipe ID2(in"r,"r))

122] Pump Output

Gbr/ft)

&bl/min)

:

:

1ty

(inches)

L029.4

(Hole ID2 1in"r,"*; - Pipe

OD21in"n".y)

I

I

1029.4 1029.4

Pump Output@bvstk) x Pump Speed 1,p*;

t23l Annular Veiocity (ff/min): Pump Output gbls/min) / Annular Capacity ouvrl

UNSW

Document No.

School of Petroleum Engineering Svdnev NSW 2052

NDWCP-QA-FSA.PI

Revision No. 6 Date: 27-Jan-2006

Formula Sheet API

Page 2

of

5

IMPORTANT FORMULAE FIELD LNITS - US IMPERIAL Circulating Fresswres

l24l

Initial Circulating Pressure (p.i): Dynamic Pressure Loss

t25]

Final Circulating Pressure (psi): Dynamic Pressure Loss

126] New Pump Pressure

(p,i)

x KMD

lppgy

+ SIDPP

/ OMD

lpsi;

x (New Rate 1rp-; / Old Rate 1.p*y)

New Pump Pressure (p.i) : Old Pressuro (psi) x (New Mud DensitY

bpel

/ Old Mud DensitY

'

opel)

Tripping

t28]

Length of tubular to pull dry before overbalance is lost 1re : (Overbalance x (Casing Capacity - Metal Displ")) / (OMD x 0.052 x Metal Displ.)

ps.

1291

bbl/ft

bbl/ft

Overbalanc€ lpsi): (I{ydrostatic Pressure) : (OMD x 0.052 x TYI))

ft

t30] 1]

bbuft

bbl/fi

bbuft

Fressure Drop per ft Tripping Wet Fipe lpwrt; : (OMD x 0.052 x Closed End Displ.) i (Casing Capacity

bbuft

*

bb|fi

Closed End Displ") bbYft

FOOI{ Drill Collars (Dry)