Exam 1 Flashcards
When should you use a histogram?
when you want to see shape, spread, and frequency
When should you use a check sheet?
when you want to collect data about a process under investigation, use to tally issues
When should you use a pareto chart?
when analyzing data about the frequency of problems or causes in a process, 80/20 rule,
When should you use a fishbone diagram?
when attempting to identify the root cause of the problem, focuses on the problem not symptoms
When should you use a defect concentration map?
when trying to identify a process that cuases the defects, uses a picture of the product to show the location of the defects
When should you use a scatter plot?
useful for identifying a relationship between two continuous variables, shows how much one variable affects another, shape indicates relationship
When should you use a control chart?
tracks process over time, identifies between special and common cause variation
What is a XMR chart?
x and moving range chart based on the avg moving range, answers: is the process stable over time? How capable is the process? What is the effect of a process change on the average or range?
What is a p chart?
used to chart the percentage defective when the sample size is greater than 50, for variable or constant, binomial
What is a np chart?
used to chart the number of defective units when the subgroup size is constant, usually greater than 50, binomial
What is a c chart?
used to chart the number of defects when the subgroup size is constant, usually greater than 50, poisson distribution
What is a u chart?
used to chart the number of defects per unit when the subgroup or constant, poisson distribution
Describe the A3 process
background current conditions goals / targets analysis proposed countermeasure plan followup
What is the equation for percent rhtym time?
sum of C/O + sum of run times
availble time
What is an ideal rhythm percentage?
85%
What is the equation for inventory replenishment levels?
Rhythm demand (rhythm time * avg demand) + SS stock demand variability (z*std dev of demand * sqrt repT)+ safety stock supply variability ( z * std dev of supply * sqrt of Rept) + other cycle time demand ( other cycle time * average demand)
What is the equation for kanban?
Repd ( replenishment time * avg demand)+ safety stock demand variability (Z x STDdx Sqrt(RepT) + safety stock variability ( x STDs x Sqrt(RepT)
What are the out of control situations?
if 2/3 sucessive points fall in the area beyond 2 standard deviations from the mean either above or below
if 4/5 successive points fall in the area that is beyond one standard deviation from the mean, either above or below
if there is a run of 6 or more points that are all either succesviley higher or lower
if 8 or more points fall on either side of the mean
if 15 points in a row fall within the area on either side of the mean that is one standard deviation from the mean
What are the levels of the lean hierarchy?
MTO - pull MTO - push / pull (postponement) inventory as a control point (pull) Inventory as a control point (push / pull) MT Forecast - push/pull MT Forecast - push
What are the 8 questions when developing a future state VSM?
What is the takt time?
Will you build to the finished goods supermarket?
Where can you use continuous flow?
Where will you need to use a supermarket pull system?
Where will you schedule production pacemaker?
How will you level load the production mix?
What is your pitch?
What process improvements will be necessary to implement your future state VSM?
What is takt time? (equation)
Availble working time
customer demand
What is pitch?
takt time * packout quantity
What did Donnelly want to do to improve their current state?
switch to a true kanban system
reduce changeover time in the paint booth
smaller paint booths dedicated to families
What is little’s law?
If I have x amount of inventory, how much time does that equate to?
