CQE Statistical Process Control 3

Question 1

A Pareto chart in quality improvement is based on which principle?

Accepted Answer

80% of effects come from 20% of causes

Answer

The Pareto principle states that roughly 80% of problems stem from 20% of causes, guiding quality teams to prioritize the vital few over the trivial many.

Question 2

What is the purpose of pre-control charts compared to traditional Shewhart control charts?

Accepted Answer

They provide a simpler setup check without requiring historical data

Answer

Pre-control charts use specification limits to create zones for quick process setup verification without needing historical process data or calculated control limits.

Question 3

In a Measurement System Analysis (MSA), 'reproducibility' refers to variation caused by:

Accepted Answer

Different operators measuring the same part

Answer

Reproducibility measures the variation introduced when different operators use the same instrument to measure the same part, reflecting operator-to-operator inconsistency.

Question 4

What does the %GR&R statistic evaluate in a gauge R&R study?

Accepted Answer

The measurement system variation as a percentage of total process variation

Answer

%GR&R expresses measurement system variation (gauge repeatability and reproducibility) as a percentage of total variation, with values under 10% generally acceptable.

Question 5

Which SPC chart is most appropriate for individual measurements when subgrouping is not practical?

Accepted Answer

Individuals and Moving Range (I-MR) chart

Answer

The Individuals and Moving Range (I-MR) chart is used when only one measurement is taken at each time point, such as in chemical batch processes or slow production rates.

CQE - Certified Quality Engineer Practice Test

CQE - Certified Quality Engineer Practice Test

CQE Statistical Process Control 3