HOW TO USE VOGEL’S CHART?DONE BY: HAWAR ABDUL-KHALIQ

:EXAMPLE

Construct IPR of a vertical well in saturated oil reservoir using vogel’s method.

The following data are given:

Reservoir pressure , Pr = 2000 psi

Tested following bottom-hole pressure,

pwf =1500 psi

Tested production rate at pwf , q = 65 bpd

SOLUTION:

1 .Find pwf/pr:

Pwf/pr = 2000/1500

= 0.75

2 .Enters Vogle’s chart at y-axis:

0.75

0.40

qo/qomax = 3.

Qomax = 65/0.40

=162.5 bpd

*Find qo for pwf = 500 psi.

Pwf/pr = 500/2000

=0.25

0.40

VOQEL’S EQUATION:

qo = qomax {1- 0.2 (pwf/pr) -0.8(pwf/pr)^2}

qo = 162.5 {1 - 0.2(0.25) - 0.8(0.25)^2}

qo = 146.25

Assume another values of pwf and find qo at pwf

to construct IPR curve.qo pwf

162.4 0

146.25 500

113.75 1000

65 1500

0 2000

0204060801001201401601800

500

1000

1500

2000

2500

qo

pw

f

“IPR CURVE “

Thanks