Tubular Material Selection for HTHP Well with Example Calculation

This article demonstrates how to select material that will be suitable for high pressure, high pressure and corrosive environment. The material chart is based on the Sumitomo tubular chart.


Well conditions are as follows;

Reservoir: High pressure & high temperature gas reservoir

Reservoir Temperature: 420 F (216 C)

CO2 content: 2.9% mol

H2S:40 ppm

Chloride Ion Content in Produced Water: 150,000 ppm

Fluid saturation pressure: 10,000 psig Continue reading

API and HTHP Fluid Loss

Fluid loss is one of important drilling fluid properties and two type of fluid loss are API and HTHP fluid loss. This article will explain about both of them and effect on the drilling operation.

API Fluid Loss Test

API Fluid Loss Test (low-pressure, low-temperature filtration test) is a test used to measure a filtration of mud with ambient temperature and 100 psi differential pressure. The API fluid loss testing equipment is shown below (Figure 1).

Figure 1 - API Fluid Loss Test Kit

Figure 1 – API Fluid Loss Test Kit

How will the drilling mud be tested?

  • Place a filter
  • Add the sample into the testing chamber
  • Place the chamber in the testing kit
  • Apply 100 psi pressure
  • Record volume for 30 minutes; at the end of the test the volume of filtrate will be recorded.
  • Record thickness of filter cake

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