Foam Drilling Hydraulics

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Lesson 7

• Foam Drilling Hydraulics
• Read UDM Chapter 2.5 - 2.6
• pages 2.75-2.130
• MudLite manual Chapter 2
• pages 2.1-2.14

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Foam Drilling Hydraulics

• Circulating pressures

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Cuttings transport
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Cuttings transport (Moore)
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Cuttings transport
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Cuttings transport
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Cuttings transport

• If flow is laminar, an increase in foam viscosity
  with increasing quality will dominate the
  reduction in foam density, and the terminal
  velocity will decrease with increasing foam
  quality, until the foam breaks down into mist

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Cuttings transport

• If the flow is turbulent, the terminal velocity
  is independent of the foams viscosity.
• The terminal velocity will increase with
  increasing foam quality due to reduction in
  density

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Cuttings transport

• For typical foam drilling conditions, flow past a
  1/2 diameter cutting in a 60 quality foam at
  nearly 10,000 was transitional.
• The terminal velocity was computed to be 60 feet
  per minute

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Cuttings transport

• In transitional flow, the terminal velocity is
  sensitive to the density difference between the
  cutting and the foam, as well as the effective
  viscosity of the foam
• This is probably why foam does not show as much
  increase in cuttings transport capacity over
  water as might be expected from its viscosity

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Circulating pressures

• Strongly influenced by viscosity and quality.
• Both viscosity and quality change with changing
  pressure.

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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Circulating pressures
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Injection Rates
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Injection Rates
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Injection Rates
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Injection Rates
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Injection Rates
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Injection Rates