## 4 Field Applications Using the Novel Cutting Transport Ratio
### Application of CTR\({}_{\text{m}}\) in Offshore Well-C and Well-D  
In Figure 6a, a case involving Well-C which was a vertical gas well, CTR\({}_{\text{m}}\) was utilized during drilling to optimize the ROP. At a depth of 3250 ft, the CTR\({}_{\text{m}}\) value was above 0.6, which suggests that the wellbore was approximately clean and free from cutting accumulation. The drilling crew did not notice any other indications of cutting accumulation or issues such as stuck pipes. However, when the drilling reached a depth of X3423 ft, the CTR\({}_{\text{m}}\) value began to steadily decrease from 0.6 until it eventually dropped to less than 0.5 at X3439 ft due to the fact that there had been some complications during the drilling process in formation, which can affect the ability to remove cuttings effectively, leading to a sudden decrease in hole cleaning efficiency. On the other hand, as shown in Figure 6b, Well-D was a horizontal well that was the subject of a particular case. Moreover, the average \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{6}{c}{**Performance of Well-A Employing CTR\({}_{\text{m}}\)**} \\ \hline
**Items** & **Output** & **Minimum** & **Maximum** & **Average** & **Remark** \\ \hline
1 & CTR\({}_{\text{m}}\) & 0.49 & 0.79 & 0.64 & Effective hole cleaning \\
2 & ROP & 120 & 280 & 205 & Improved the drilling performance due to optimized efficiency of hole cleaning \\ \hline \hline \multicolumn{6}{c}{**Performance of Well-B Employing CTR\({}_{\text{m}}\)**} \\ \hline
**Items** & **Output** & **Minimum** & **Maximum** & **Average** & **Remark** \\ \hline
1 & CTR\({}_{\text{m}}\) & 0.39 & 0.49 & 0.44 & Improper removal of cuttings from the wellbore \\
2 & ROP & 105 & 264 & 135 & Decreased drilling efficiency and performance \\  & & & & & attributable to inefficient wellbore cleaning \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Impact of employing CTR\({}_{\text{m}}\). of the \(\text{CTR}_{\text{m}}\) was 0.45, which indicated inefficient hole cleaning, due to the stuck pipe, which can be noticed at depth X3850-X400 ft (see Figure 6b). Generally, poor wellbore cleaning can result in the accumulation of cuttings and other debris in the wellbore, leading to reduced drilling efficiency and an increased risk of complications. Similarly, stuck pipe incidents can significantly impede drilling progress and result in costly downtime. By addressing these issues promptly and effectively, drilling operations can maintain optimal performance and avoid potential delays and complications. Employing efficient wellbore cleaning techniques such as the novel \(\text{CTR}_{\text{m}}\) model can help improve drilling efficiency and prevent issues related to stuck pipes. It is essential to continuously monitor and evaluate drilling operations to identify potential issues and take proactive steps to address them in a timely manner. Table 5 provides a summary of the impact of implementing \(\text{CTR}_{\text{m}}\) on well performance, particularly in relation to the enhanced hole cleaning achieved in the vertical gas well, Well-C. The average \(\text{CTR}_{\text{m}}\) value in Well-C was over 0.57, and the average ROP was 14.3 ft/hr. These results demonstrate the positive impact of effective wellbore cleaning and the successful implementation of the \(\text{CTR}_{\text{m}}\) model on drilling performance. In contrast, the average \(\text{CTR}_{\text{m}}\) value in the horizontal well, Well-D, was 0.45, which is below the limited value due to stuck pipe issues. The average ROP in Well-D was 93.4 ft/hr, which was also affected by inefficient wellbore cleaning and stuck pipe incidents. These results highlight the importance of identifying and addressing issues related to wellbore cleaning and stuck pipe promptly to maintain optimal drilling performance and prevent costly downtime. Based on the results above, in Well-A, the novel \(\text{CTR}_{\text{m}}\) model improved the rate of penetration by 52% compared to Well-B.