OVERVIEW OF SPCBPT 2423 – STATISTICAL PROCESS CONTROL

Customer

Supplier

Order

Demand Forecast

Prod. Plan Control

Inventory Control

Purchase Order

Manufacturing

Planned Maintenance

Industrial Engineering

Quality Management

Finance & Management

Business Dev. & Marketing

Manufacturing Process Flow

INTRODUCTION

Delivery Quality Customer Satisfaction

Buying Products

Produced by a process that is stable or

repeatable

Process must be capable of operating with little variability around the target or nominal

dimensions of the product’s quality characteristics

USE OF SPC IN QUALITY SPC is most effective when it is integrated into an overall

companywide quality improvement program To improve quality and productivity – start with managing

facts and data and not simply rely on judgment

Processes do not naturally operate in an in-control state

Use of control

charts in an SPC program

To eliminate assignable causes,

reduce process variability and

stabilize process performance

Example of Products

USE OF SPC IN QUALITY

Products

Process Control

Process Flow

Process Data

USE OF SPC IN QUALITYChance and Assignable Causes Chance / Common Causes

small random changes in the process that cannot be avoided – due to the inherent variation present in all processes

only removable by making a change in the existing process – involves management intervention

Example : temperature in the factory building

Assignable Causes variations in the process that can be identified as having a

specific cause (causes that are not part of the process on a regular basis)

variation arises because of specific circumstances Example : changes in the thickness of incoming raw

material, broken tool Source of variation : process itself, the material used, the

operator’s actions or the environment

USE OF SPC IN QUALITY Elements of a Successful SPC Program

1. Management leadership2. A team approach, focusing on project-oriented

applications3. Education of employees at all levels4. Emphasis on reducing variability5. Measuring success in quantitative (economic)

terms6. A mechanism for communicating successful

results throughout the organization

APPLICATION OF SPC

Define

Opportunity

•Identify and/or validate the business

•Define critical customer requirements

•Establish project charter, build team and document (map) processes

Measure

Performance

•Determine what to measure and sigma performance level

•Manage measurement data collection

•Develop and validate measurement systems

Analyze Opportunity

•Analyze data to understand reasons for variation and identify potential root causes

•Determine process capability, throughput, cycle time

•Formulate investigate and verify root cause hypotheses

Improve

Performance

•Generate and quantify potential solutions

•Evaluate and select final solution

•Verify and gain approval for final solution

Control Performance

•Develop ongoing process management plans and find mistake-proof process

•Monitor and control critical process characteristics

•Develop out of control action plans

APPLICATION OF SPC

Statistical Process Control

Manufacturing Nonmanufacturing / Service Businesses

APPLICATION OF SPC Service industry applications of SPC and related

methodology sometimes require ingenuity beyond that normally required for the more typical manufacturing applications.

Two primary reasons for this difference :1. Most service businesses do not have a natural

measurement system that allows the analyst to easily define quality

2. The system that is to be improved is usually fairly obvious in a manufacturing setting, whereas the observability of the process in a nonmanufacturing setting may be fairly low

Key to applying SPC in a nonmanufaturing environment is to focus initial efforts on resolving these two issues.