If friction is measured at specific depths, enter the friction in corresponding cells of the table and leave the rest of cells in friction column empty. NovoBPT will automatically interpolate frictions in other depths. Then at each depth, net friction is calculated as below:

 

'Net Friction' = 'Measured Friction - ('Weight of Bit' + 'Weight of Scale Coupler' + 'Weight of Casing Per Unit Length' * Z)

 

To view the plot of net casing friction versus depth, click on the 'Friction Plot' tab at the right side of the page.