Horizontal Deviation (msHD)
Definition - What does Horizontal Deviation (msHD) mean?
Horizontal deviation (msHD) describes the differences between the actual and planned paths of directional drilling in terms of “left” and “right”. It is a lineal deviation measured in feet. It is a component of technical hole deviation. The measurement msHD stands in direct contrast to vertical deviation (msVD) in a horizontal directional drilling process.
Trenchlesspedia explains Horizontal Deviation (msHD)
The perspective for the horizontal aspect of these components is to look down the planned hole – in the mind’s eye. A horizontal deviation is a lineal difference that may be thought of as occurring on the left or right.
Technical hole deviation is made up of eight components. Four of these are horizontal and four are vertical. The msHD calculation is captured using technical hole deviation logging. Differences noted between the planned and actual paths contribute to the quality control of the directional steering process.