Control Charts & Analysis Flashcards
6 cards from real SPC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Control Charts & Analysis flashcards as text
What is the purpose of the center line on a control chart?
Answer: Process mean
The center line represents the average or mean of the process and serves as a reference for detecting variation.
What does it indicate when points trend steadily upward on a control chart?
Answer: Possible process shift
A continuous upward trend may signal a shift in the process mean, requiring investigation.
Which type of control chart is best for monitoring process variability?
Answer: R-chart
R-charts monitor the range of variation within subgroups, making them useful for detecting shifts in variability.
How many standard deviations from the mean are typical control limits set at?
Answer: 3
Control limits are generally placed at ±3 standard deviations to detect statistically significant variation.
Which of the following may indicate a process is out of control?
Answer: One point outside control limits
A single point outside the control limits is a common signal that the process may be out of control.
What is the main difference between control limits and specification limits?
Answer: Control limits are process-based
Control limits reflect process performance; specification limits are customer or design requirements.