List of top Manufacturing Processes II Questions

During straight turning of a 20 mm diameter steel bar at a spindle speed of 400 RPM with an HSS tool, a tool life of 10 minutes was observed. When the same bar was turned at 200 RPM, the tool life increased to 40 minutes. The tool life (in minute) while machining the bar at 300 RPM is \(\underline{\hspace{2cm}}\). [round off to nearest integer]

A cylindrical workpiece is turned using two different tools. Tool 1 has zero nose radius; the side and end cutting edge angles are \(20^\circ\) and \(10^\circ\), respectively. Tool 2 has a 0.5 mm nose radius. Both tools machine at a feed of \(0.2\ \text{mm/rev}\). The ratio of the ideal maximum height of unevenness on the surface produced by Tool 1 to that produced by Tool 2 is \(\underline{\hspace{2cm}}\) (round off to one decimal place).

For an electrochemical machining process \[ \frac{dy}{dt}=\frac{\lambda}{y}-f , \] where $y$ is the inter-electrode gap in mm at time $t$ (in minute), and $f$ is the feed of the tool in mm/minute. The value of $\lambda$ is $6\times10^{-3}$ cm$^{2}$/minute. For maintaining a constant inter-electrode gap of 0.1 mm, the feed (in mm/minute) should be \(\underline{\hspace{2cm}}\). [round off to one decimal place]
The worktable of an open loop positioning system is driven by a lead screw with a pitch of 4 mm. The lead screw is connected to the shaft of a stepper motor. A gear of 80 teeth mounted on the stepper motor shaft meshes with a gear of 20 teeth mounted on the lead screw. The step angle of the stepper motor is $9^\circ$. The number of pulses required to move the table by 200 mm is \(\underline{\hspace{2cm}}\). [in integer]
In an electro-discharge machining process, the discharge voltage is $V_b$. The energy dissipated per spark across the inter-electrode gap is proportional to
Match the codes used in CNC part programming with their functions.\[\begin{array}{c c | c c} \hline \textbf{Code} & & \textbf{Function} & \\ \text{P} & \text{G91} & \text{1} & \text{End of program} \\ \hline \text{Q} & \text{M02} & \text{2} & \text{Programming in incremental coordinates} \\ \hline \text{R} & \text{G32} & \text{3} & \text{Spindle stop} \\ \hline \text{S} & \text{M05} & \text{4} & \text{Thread cutting in turning} \\ \hline \end{array}\]
In the classical economic order quantity (EOQ) model, let \( Q \) and \( C \) denote the optimal order quantity and the corresponding minimum total annual cost (the sum of the inventory holding and ordering costs). If the order quantity is estimated incorrectly as \( Q' = 2Q \), then the corresponding total annual cost \( C' \) is