Figuring Control Limits

Calculate the grand average (x-Double Bar)

37.4+36.4+32.4+46.6+40.8+36.8+37.4+40+37.2+36 divided by 10 = 38.1

Calculate the average range (R-Bar)

12+14+21+11+22+20+22+17+23+19 divided by 10

= 18.1

NOTE: A2 is a constant that varies based upon sample size and is found in standard statistical tables.

Calculate upper and lower control limits for the averages.

Calculate upper and lower control limits for the ranges.

NOTE: D3 and D4 are constants that varies based upon sample size and is found in standard statistical tables.

Draw Limit Lines!

Draw limits on chart.

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	The. Deming PDCA Cycle	QMS Implementation	FMEA Information	APQP Information
Auditing Information	8-D Problem Solving	Statistics	Error Proofing (Poka Yoke)	Brainstorming
Identifying Waste	Pull Systems	Lead Time Reduction	Planned Maintenance	Quick Setup
Discovering Change	Process Capability - Cp vs. Cpk	Histogram. Animation	Process Loop Animation	Taguchi Loss Function
		Fishbone / Cause and Effects Animation

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