Customer Requirements
A manufacture of molded parts who supplies a major medical disposable company needed an inspection system to measure rubber pats critical used in the syringe. The OD and TIR and Wall Thickness of the round part are critical to the proper performance of the device. Currently samples of these parts are removed from production and inspected. In order to meet the requirements for inspection the special measurement system was devised using an existing measuring system and special software to provide the data analysis.

Customer Requirements
The specific requirement were for a non-contact measurement system that could take measurements at 16 evenly spaced angular positions as the part is rotated through 360 degrees. The TIR would be the result of the change in distance form the edge of the part to a reference edge and the wall thickness as the distance from the support pin before the part is mounted to the edge of the part after the part is mounted.

The samples are supplied in batches. SPC calculations were to be performed on the batch and the data was to be printed to a report and saved to a database.

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Operators screen that displays each part being measured with each measurement at each rotation location. The raw measurements are shown in the lower right corner.

Solution
The operator needed only to insert the part from each specific mold on the pin supplied - orienting properly to maintain a reference position relative to the position of the part in the mold.
Each part is measured in succession with the relative measurement form the edge of the part to a reference edge at each rotation position collected by the program. At the end of a complete revolution the wall measurement and the TIR is calculated at each angular position. The results are added to a table.

At the end of the batch of inspected parts the SPC values are calculated and a complete report is printed. The report includes the TIR, WALL and OD values, PSC values for each characteristic and a chart that depicts the mold pattern. This chart indicates the angular position of the maximum TIR location and the values. This "mold map" helps the used determine the flow characteristics of the mold.

All of the data is archived and a report can be re-printed aa required. Also the database can interface with other programs for further data analysis.

Results
The customer was able to meet both the in-house as well as the customer inspection requirements with a minimum of operator time.