Question $4$

A certain batch consists of $100$ units. The company makes $300$ of these batches per year. The entire manufacturing process involves $5$ machines. Other pertinent data is as follows:

$-$ Average setup time for the machines is $1$ hours.

$-$ Average operation time is $15$ min per unit and

$-$ Average non$-$operation time is $3$ hours.

There are $20$ machines in the plant that are used for processing. The plant operates one $8$ hour shift per day, $5$ days a week, and $250$ days per year. If waste is negligible, determine:

$4\mathrm{.}1$ The manufacturing lead$-$time for a batch

$4\mathrm{.}2$ The annual plant capacity

$4\mathrm{.}3$ The plant utilization

Question $5$

An industrial furnace is to be controlled as follows: The contacts of a bimetallic strip inside the furnace close if the temperature falls below the set point, and open when the temperature is above the set point. The contacts regulate a control relay which turns on and off the heating elements of the furnace. If the door to the furnace is opened, the heating elements are temporarily turned off until the door is closed.

Let $\backslash (\backslash$mathrm$\{$X$\}1=\backslash )$ temperature below set point, $\backslash (\backslash$mathrm$\{$X$\}2=\backslash )$ door closed, $\backslash (\backslash$mathrm$\{$Y$\}1=\backslash )$ furnace on$.$

$5\mathrm{.}1$ Construct the ladder logic diagram for the system

$5\mathrm{.}2$ Write the low level language statements for the system

Question $6$

There are $8$ machines in the automatic lathe section of a certain machine shop. The setup time on an automatic lathe averages $4$ hours. The average batch size for parts processed through the section is $10.$ The average operation time $\backslash (=2\mathrm{.}0\backslash )$ minutes.

The section runs one $8-$hour shift per day, $5$ days per week. However, an average of $\backslash (10\backslash \%\backslash )$ of the production time is lost due to machine breakdowns. Scrap losses are negligible.

$6\mathrm{.}1$ Calculate the Production rate

$6\mathrm{.}2$ Calculate the production capacity.

$6\mathrm{.}3$ Calculate the Work in process if availability is $0\mathrm{.}95$ and utilization $\backslash (=90\backslash \%\backslash )$