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•Calculates bottom hole static temperature (BHST) or temperature gradient (TG)
•Calculates bottom hole circulating temperature (BHCT)
•Supports US and Metric units
•Utilizes methodologies and data found in API Recommended Practice 10B-2 Second Edition, April 2013

•True Vertical Depth (1000 - 22000 ft and 300 - 6600 m)
•Measured Depth (≥ True Vertical Depth)
•Temperature Gradient (0.7 - 1.9 °F/100 ft and 1.6 - 3.6 °C/100 m)
•Bottom Hole Static Temperature (87 - 498 °F and 32 - 264 °C)

•Bottom Hole Static Temperature (°F or °C)
•Bottom Hole Circulating Temperature (°F or °C)
•Temperature Gradient (°F/100 ft or °C/100 m)

The tables in Annex D of API RP 10B-2 are a matrix of predicted circulating temperatures for the following well simulation schedules as a function of true vertical depth and temperature gradient.


Temperature predictions are given for true vertical depths ranging from 1,000 ft to 22,000 ft for US units and 300 m to 6,600 m for metric units and temperature gradients ranging from 0.9 to 1.9 for US units and 1.6 to 3.6 for metric units.

To predict bottom hole temperatures, BHT utilizes a standard regression technique. This technique, when used in combination with cited tables in API RP 10B-2 Annex D, allows BHT to predict bottom hole temperatures for any depth-gradient input combination that fall within the bounds of relevant tables.

Smaller temperature gradients than those listed in Annex D have been extrapolated from 0.9 °F/100 ft down to 0.7 °F/100 ft in response to a customer request. Temperature predictions for this gradient range utilize the same regression technique referenced above.

*Note: No extrapolation is performed when using metric units

If the user-defined measured depth value is greater than true vertical depth by 1,000 ft or more or 300 m or more, the well is assumed to be highly deviated, lateral, or horizontal and the predicted bottom hole circulation temperature is set equivalent to the bottom hole static temperature value.

As awesome as we think we are, we know we’re not perfect. What you have is our first attempt to address what we perceived the core needs of our target audience to be. As you begin to integrate this app into your work life we expect errors, short-comings and worthwhile enhancements to become apparent.

While we welcome praise, we find constructive (and respectful) criticism to be of more value. Please don’t hesitate to send us thoughts, comments and questions on any of our products or new products you would like to see. founders@threeedev.com

What's New

Version 3.4.6

UI Enhancements to make it more user-friendly


3E Development, LLC
2.4 MB
Requires iOS 7.0 or later. Compatible with iPhone, iPad and iPod touch.
Age Rating
Rated 4+
© 3E Development, LLC
USD 0.99


  • Family Sharing

    Up to six family members will be able to use this app with Family Sharing enabled.

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