Compute and plot annual and cumulative uranium requirements

Compute and plot annual and cumulative uranium requirements through the year 20 15
for the projected nuclear electric capacities given in Table 4.8 for each of the following
assumptions: (a) all reactors are PWRs with no recycling; (b) all reactors are PWRs,
and all operate with recycling after 2000; (c) all reactors are PWRs until 2000 after
which 20% of new reactors are LMFBRs.

Table 4.8

Solution

Changeover of fixtures on a machine takes 35 minutes. Following changeover an average of 5 parts must be produced and discarded before correct sitting is achieved. The machine cycle time for each part is 2 minutes and the materials cost is $1.50. The labour cost for a skilled set up person is $45 per hour while the machine operator is paid $30 per hour. Current batch size is 50. Suppose the set up time can be reduced so that the operator can perform the changeover and on average only two parts are required before correct setting is achieved, what should be the new set up time so that a batch size of 20 could be produced with only 90% of the current cost per unit? The cost per unit is the total of material cost, labour of set up and labour cost of running the machine.