## 3 Case Study of Boiler System Used in Textile Process Industries
\begin{table}
\begin{tabular}{l l l l l l l l l l} \hline \hline \multirow{2}{*}{**Component**} & \multirow{2}{*}{**Failure Mode**} & \multirow{2}{*}{**Failure Cause**} & \multirow{2}{*}{**Failure Effect**} & **SV** & **O** & **D** & **M** & **S** & **L** \\ \cline{3-10}  & & & & & & & & & & & \\ \cline{2-10}  & The strainer failure & The strainer is clogged & Pump Fails & 2.67 & 3.73 & 1.93 & 2.38 & 1.58 & 2.31 \\ \cline{2-10}  & Rust of tank & A lot of sediment in the water & \begin{tabular}{l} Failure of mechanical seal and \\ cause a leak \\ \end{tabular} & 3.11 & 3.35 & 1.96 & 2.96 & 1.87 & 2.13 \\ \cline{2-10}  & condensate is too hot for \\ the pump & steam traps fail & Failure of pump’s impeller & 2.47 & 3.84 & 1.90 & 2.38 & 1.75 & 2.15 \\ \cline{2-10}  & mechanical seal failure & Pump leakage & Pump failure & 2.70 & 3.28 & 2.31 & 3.21 & 1.84 & 2.41 \\ \cline{2-10}  & Electrical failure of the pump & The voltage supplied to the & \begin{tabular}{l} Failure of circuit breaker and \\ winding burns \\ \end{tabular} & 2.89 & 3.49 & 2.04 & 3.21 & 1.69 & 1.98 \\ \cline{2-10}  & Impeller Failure & Impeller is clogged & Mechanical failure of pump & 2.67 & 3.13 & 2.20 & 3.37 & 1.45 & 2.39 \\ \cline{2-10} Feed Water & Shaft failure & Overload work, & Pump vibration, Pump works & 3.57 & 3.06 & 2.16 & 3.38 & 1.16 & 2.44 \\ \cline{2-10} Pump & Shaft failure & Maslignment, Corrosion & \begin{tabular}{l} Turbulent flow \\ but does not provide flow \\ \end{tabular} & 2.71 & 3.16 & 2.44 & 3.44 & 1.42 & 2.32 \\ \cline{2-10}  & Deterioration of the bearings & Improper mountings & Pump vibrates or is noisy. & 2.71 & 3.48 & 2.32 & 3.10 & 1.34 & 2.24 \\ \cline{2-10}  & Abnormal load on motor & Pump failure & 3.37 & 3.24 & 2.50 & 3.25 & 1.28 & 2.54 \\ \cline{2-10}  & Contamination present & Pump failure & 2.25 & 3.52 & 2.29 & 3.33 & 1.40 & 2.21 \\ \cline{2-10}  & Pump housing solute & Cavitation, corrosion & \
\begin{tabular}{l} Cavitation, corrosion \\ and Vibration \\ \end{tabular} & Leak in the pump body & 2.80 & 2.92 & 1.97 & 3.28 & 1.56 & 2.46 \\ \cline{2-10}  & Pump low efficiency & Electric motor failed &
\begin{tabular}{l} Low flow warming \\ \end{tabular} & 2.63 & 2.89 & 2.10 & 3.18 & 1.38 & 2.75 \\ \cline{2-10}  & Reduction in pump pressure & Pump cavitation & Pump noise and vibration & 3.02 & 2.88 & 2.31 & 3.31 & 1.77 & 2.04 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: _Cont._The mean values of the normalized data for each risk factors are calculated using Equation (3) and are as follows;  
\(\text{N}_{\text{SV}}\) = 0.7069, \(\text{N}_{\text{O}}\) = 0.8048, \(\text{N}_{\text{D}}\) = 0.8280, \(\text{N}_{\text{M}}\) = 0.7820, \(\text{N}_{\text{S}}\) = 0.6998, \(\text{N}_{\text{L}}\) = 0.7894. * **Step 7:** Calculate the values of the variation of preferences. In this step, preference variation values for all risk factors are calculated using Equation (4), and its values are \(\varphi_{\text{SV}}\) = 0.0287, \(\varphi_{\text{O}}\) = 0.0072, \(\varphi_{\text{D}}\) = 0.0097, \(\varphi_{\text{M}}\) = 0.0080, \(\varphi_{\text{S}}\) = 0.0190, \(\varphi_{\text{L}}\) = 0.0158. * **Step 8:** Calculate the deviations in the value of preference for all criteria. Deviations in the preference values for all the risk factors are calculated by using Equation (5), and its values are \(\Omega_{\text{SV}}\) = 0.9713, \(\Omega_{\text{O}}\) = 0.9928, \(\Omega_{\text{D}}\) = 0.9903, \(\Omega_{\text{M}}\) = 0.9920, \(\Omega_{\text{S}}\) = 0.9810 and \(\Omega_{\text{L}}\) = 0.9842. * **Step 9:** Calculate the overall criteria weights for all criteria. The overall criteria weights for all risk factors are computed by Equation (6), and their values are \(w_{\text{SV}}\) = 0.1643, \(w_{\text{O}}\) = 0.1679, \(w_{\text{D}}\) = 0.1675, \(w_{\text{M}}\) = 0.1678, \(w_{\text{S}}\) = 0.1659 and \(w_{\text{L}}\) = 0.1665. * **Step 10:** Results obtained after preparing a matrix by multiplying \(N_{ij}\) and \(w_{j}\). In this step, the overall risk factors matrix is prepared by multiplying \(N_{ij}\) and \(w_{j}\).