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both a Setup Sheet and Process sheet are necessary
Definitions: Set up sheet; 1) a document, instructions for setting a piece of apparatus, 2) to place in a particular position/ setting Process sheet 1) procedures that take place 2)a course /process 3) results orientated
Understanding the difference between a set up sheet and process sheet can be night and day or the same thing dependent on the shop and design of what is used to set a machine and process. A comparison from a quality standpoint might be the difference between a design print to build said part and the quality print which is for production of parts.
A set up sheet allows one to set up the machine (now a days more and more these data points are stored in a machine). This includes where to set the switches and functions of the machine. For example the barrel temperatures, back pressure, screw RPM/screw circumferential speed, injection speed, shot size, pressures and mold temperature sets, to name a few.
These settings get the part process running, and allow the personnel on off shifts to set up and start the process that was documented per those settings to start.
The question is: IS the process the same? In a simple answer we do not know. The reason being is that while the machine is set the same, is there a confirmation that the process is the same?
An example:
While barrel settings, back pressure, and RPM are set correctly to a previous set up the result that is looked for or for which there is a concern is what is the temperature of the material begin produced , i.e. the melt temperature. This is a result of the various settings; some may say a consequence of those settings and unfortunately today we cannot set in a machine to the melt temperature that is necessary and then a machine changes the variables to achieve this point.
Thus as shown above the set-up sheet needs to have a check and or as the might be called a process sheet.
The process sheet would be the result of the machine setup for that mold, or stated another way the conditions within or affect the mold for processing. The results of machine settings for a repeatable process are; fill time, melt temperature, steel temperature, plastic pressure for packing**, shot weight at transfer, cycle time and possibly references to RV valves, and other points which are results or consequences to the machine settings.
** Plastic pressure for packing is a direct setup sheet result for electric machines, and a calculated results for those with hydraulic. It is one which is directly transferable to a process sheet from the set up sheet.
An example:
Fill time is the result of the injection speed and available pressure which are set on the machine. Injection speed can be set in mm/sec, cmᶟ/sec etc., while position of transfer can be set in mm, inches or Cubic's on the machine with pressure available set at various set points, all of which can influences the result of what is referred to as fill time. Fill time cannot be set on the machine, it can only be viewed as a result of machine setting, but is a check that within the mold the plastic is flowing the same this production run as the last.
Combining the two
In many plants the two sheets are combined and or as is the case the setup sheet is being modified to include results data. This data is sometimes included next to setup data which affects this result, or sometimes in a specifically noted area. From a clarity standpoint the author believes a separate area on the sheet with all process conditions listed is better. This is for a clarity standpoint, it is all there, and from a monitoring standpoint a quick glance at this area and confirmation to the screen should confirm that the process is the same.
In short a SETUP sheet helps in setting a machine up for the production of parts, and the PROCESS sheet (area)clarifies that the setup is correct for the production of the parts, that they were made under the same conditions within the mold (our factory). It can be further stated that the process sheet should not change once established, but the setup sheet may change for which ever machine the mold goes to, so as to maintain the process.
SLSILVEY
06072014
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