Exam Questions Flashcards
List SIX (but NOT more than six) typical facilities for handling materials in manufacturing systems
- Unloading Facility.
- Storage Facility.
- In-Process Facility.
- Interdependent Facility.
- Auxiliary Function Facility.
- Packaging Facility.
- Shipping Facility.
Use bullet points to outline FOUR (but NOT more than four) basic simulation methods
- Monte Carlo Method
- Computer Generated Graphics
- Computer Generated Tables
- Java Applets
- Computer Simulation Methods
What is the equations used to find material removal rate for a cutting tool?
Q = (v_f * a_p * a_e)/1000
For twist drill though (apparently) we replace a_p*a_e with the area of the hole
What equation can we use to find the required number of rpm for a cutting tool?
N = (1000 * Q_max)/(Z * f_z * a_p * a_e)
What is the equation used to find the feed rate for a cutting tool?
v_f = f_z * Z * N
What is the equation used to find cutting velocity?
v_c = (Pi * D * N)/1000
What are the definitions and units of the following cutter tool parameters: N, D, v_c, Z, f_z, v_f, a_p, a_e, and Q?
N = revolutions per minute of cutter tool D = cutter diameter (mm) v_c = surface cutting velocity (m/min) Z = number of teeth/flutes f_z = feed per tooth (mm/rev), chip load v_f = feed rate (mm/min) a_p = depth of cut (mm) a_e = width of cut (mm) Q = material removal rate (cm^3/min)
List two advantages and two disadvantages of Kanban systems
Advantages: Efficient tracking of lots, Inexpensive implementation of JIT
Disadvantages: Slow to react to changes in demand, Ignores predicted demand patterns
Why is it important to account for the ‘learning curve’ effect for short to medium length production runs?
In reality, learning flattens out, so it is more useful and appropriate in this time region
Machining conditions have an impact on tool wear/tool life. What are the two main types of wear?
Flank wear - occurs due to abrasion of tool with part machined surface
Crater wear - caused by erosion due to sliding of chips on tool rake face
What does VB represent when looking at tool life? How does it vary with time? How does it vary with cutting speed?
Flank wear. Three stages - primary/initial wear, steady-state wear, tertiary/accelerated wear.
Faster cutting speed results in decrease in tool life
What is Taylor’s formula?
v*T^n = C v is the cutting speed T is the tool life (related to flank wear, VB) n depends on other cutting parameters C is a constant
What is the extended Taylor’s formula? What is the order of importance of the variables on tool life, and why?
vT^n(v_f)^a*(a_p)^b = C
Since b<a></a>
