PQPR 分析.ppt

 “Lean” Tools  PQ Analysis P-Q Analysis The best way to begin an effort to build a U-shaped “Flow” cell for wide variety small lot production is to study the current production conditions that exist in the factory. This is done through the use of a P-Q analysis. In a P-Q analysis, the P stands for product and the Q stands for quantify (no consideration to dollar value). Step 1: Obtain at least 6 months of data on products made and production output quantities. (If known, future production quantities would be better.) Step 2: List the products in order of highest quantity output and their associated percentage output of the total and tabulate on a P-Q list (see table 1). P-Q Analysis Step 3: Create a P-Q Analysis table (see table 2), with the left vertical axis representing the output quantity and the horizontal axis representing the product. The graph is a Pareto chart, listing the products and their quantities in descending order, and a cumulative percentage line (right vertical axis). Note: Technically, in a wide variety small lot production shop, 40% of the product accounts for approximately 60% of the volume (or less). In the above example 40% of 14 total part number’s is approximately. 6. Draw a vertical line through the 6th product until you hit the cumulative % line, and draw a horizontal line over until you intersect the right axis. In this example it intersects around 70%, and approximates a true wide variety small lot factory. P-Q Analysis Step 4: Design a line of processes based on the P-Q Analysis list. If the P-Q Analysis shows that 20% of the parts represent 80% of the volume; then each product should be investigated for a single product cell (the relative volume probably already requires dedicated equipment). P-Q Analysis In a wide variety small lot factory depicted below (see table 3), Group Technology or families must be identified through the use of a Process-Route (PR) Analysis (described in the next section). In th