A company which produces railway sleepers for rail infrastructure projects, is seeking to improve its product...

   

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A company which produces railway sleepers for rail infrastructure projects, is seeking to improve its product quality and reliability. The company has provided the following qualitative and quantitative data related to its current operation. Prepare an individual report to carry out the evaluation and answer the following four questions. Q1. The company has kept at one of its plants 24 months records of the total number of failures occurring each month, as shown in Table Q1. Produce the 3-month moving average and the 6-month moving average plots, together with the CUSUM plot (if the target value is 15). Table Q1 Month 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Failures 18 20 16 10 12 18 15 11 13 15 15 22 12 17 15 14 9 13 13 17 16 18 14 21 Q2. A machine used in a process has an MTBF of 400 hours and an MTTR of 8 hours. 1) Calculate its availability. 2) The target availability is to be 99.9% to meet demands. If the machine's availability is less than this value, then an option is to add identical machines as a stand-by. How many additional machines would be needed to meet the target availability? Justify your answer. 3) The cost of the machine is £350,000 and the downtime time cost of the process is £5000 per hour. For this new stand-by arrangement, what is the payback period? A company which produces railway sleepers for rail infrastructure projects, is seeking to improve its product quality and reliability. The company has provided the following qualitative and quantitative data related to its current operation. Prepare an individual report to carry out the evaluation and answer the following four questions. Q1. The company has kept at one of its plants 24 months records of the total number of failures occurring each month, as shown in Table Q1. Produce the 3-month moving average and the 6-month moving average plots, together with the CUSUM plot (if the target value is 15). Table Q1 Month 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Failures 18 20 16 10 12 18 15 11 13 15 15 22 12 17 15 14 9 13 13 17 16 18 14 21 Q2. A machine used in a process has an MTBF of 400 hours and an MTTR of 8 hours. 1) Calculate its availability. 2) The target availability is to be 99.9% to meet demands. If the machine's availability is less than this value, then an option is to add identical machines as a stand-by. How many additional machines would be needed to meet the target availability? Justify your answer. 3) The cost of the machine is £350,000 and the downtime time cost of the process is £5000 per hour. For this new stand-by arrangement, what is the payback period?