Tripability Analysis of Casing Strings in Directional Wells Using the Continuous Beam-Column and Buckling Theory

Table 3

Comparison of model prediction errors.

Wellbore	Relative error (%)
	Johancsik’s model	Huang’s model	Fan’s model	This paper’s model
Vertical section	33.22	31.64	15.98	15.94
	25.08	23.50	15.87	14.09
	13.81	10.56	−1.91	4.60
Build-up section	17.10	9.01	−2.54	7.80
	4.63	−1.92	−5.56	1.33
	9.20	2.70	0.03	7.34
Sail section	2.81	−1.70	−2.01	3.97
	−1.34	−5.16	−2.56	2.80
	−5.08	−8.38	−4.70	0.21
Drop-off section	−6.31	−9.40	−4.27	0.52
	−10.70	−15.04	−8.34	−2.72
	−16.18	−19.14	−10.58	−5.25
Inclined section	−10.43	−14.64	−3.75	0.02
	−10.43	−14.54	−3.83	−0.33
	−10.21	−14.18	−3.70	−0.61
Root mean square error (%)	14.36	14.52	7.41	6.58