Quality Control & Process Improvement Flashcards

During a post-project quality review, the team discovers that trench wall collapses occurred more frequently in sandy soil than in clay. This relationship is best analyzed using a:

Answer: Scatter diagram correlating soil type with collapse frequency

A scatter diagram plots two variables against each other to reveal whether a correlation exists, making it ideal for comparing soil type to collapse frequency.

What is the primary benefit of standardizing mini excavator pre-shift inspection procedures across an entire fleet?

Answer: It ensures consistent quality data collection, enabling meaningful fleet-wide comparisons and trend analysis

Standardized procedures produce comparable data across machines and operators, which is essential for identifying systemic issues versus one-off problems.

An operator is told to implement 'error-proofing' (poka-yoke) on a repetitive bucket attachment change. An example of this would be:

Answer: Designing a color-coded pin that only fits one orientation of the quick coupler

Poka-yoke devices make it physically impossible or immediately obvious when an error is about to occur, eliminating reliance on memory or attention.

Which metric directly indicates whether a mini excavator is being used productively versus sitting idle?

Answer: Overall Equipment Effectiveness (OEE)

OEE combines availability, performance, and quality into a single score that reveals how productively a machine is being utilized during scheduled time.

A quality improvement team wants to reduce hydraulic fluid contamination in mini excavators. The most effective way to verify the improvement after a change is made is to:

Answer: Collect fluid samples before and after the change and compare particle count data

Objective before-and-after data (fluid particle counts) provides measurable evidence that the change actually reduced contamination.

When completing a quality non-conformance report (NCR) for an excavation that missed the specified grade, the operator should include:

Answer: The location, magnitude of deviation, probable cause, and corrective action taken

A complete NCR captures what happened, how far off it was, why it happened, and how it was fixed, providing a full record for quality improvement.

In continuous improvement terms, 'value-added' excavation activity is best defined as:

Answer: A step that directly transforms the work product in a way the customer requires and is willing to pay for

Value-added work is defined from the customer's perspective: it must change the product, be done right the first time, and be something the customer actually values.