Basic Concept

Using the triangle, find the fluid weight necessary to equal 3500 psi if the fluid

height is 6500 TVD

• 10.3 ppg

• 10.7 ppg

• 10.4 ppg

• 10.5 ppg

Calculate the ECD in forward circulation:
- Fluid weight: 12 ppg
- Depth: 10,000 ft MD/8000 ft TVD
- Pump pressure: 3300 psi
- Friction pressure in tubing: 1000 psi
- Friction pressure across the mill: 2100 psi

• 13.0 ppg

• 13.1 ppg

• 12.8 ppg

• 12.5 ppg

Calculate pressure gradient (psi/ft) for a fluid with density of 10.3 ppg

Calculate EMW for a formation with gradient of 0.57 psi/ft

A gas bubble at 8000’ TVD is 6 bbls.  What is the volume of the gas bubble if it reaches surface.  The gas is allowed to expand.

Hint: Use Boyle’s Law to solve for Volume_2

• Surface psi = 14.7 psi (Atmospheric)

• Fluid weight = 8.5 ppg

• Bubble pressure @ 8000 ft = HP at 8000 ft