Calculating Screw Speed

The following is a formula which can be used to quickly determine the screw speed during setup. This is based on consuming 80% of the cooling time for shot recovery.

Question: Could you provide me with a quick formula my setup techs can use to estimate the final screw speed?
My Response: This is a quick set of calculations for determining the screw speed to consume 80% of the cooling time:
(RTdesired)= (tcool) x (0.8)

(RPMfinal= (RPMcurrent) x (RTcurrent) รท (RTdesired)

Symbol Key
RTdesired  = Desired Recovery Time
RTcurrent   = Current Recovery Time
RPMfinal  = Final RPM Setting
RPMcurrent  = Current RPM Setting
Additional Thoughts
If you put this into a spreadsheet, then the technician would only have to enter the Current Screw Speed, Current Recovery Time, and Cooling Time.
(RPMfinal= (RPMcurrent) x (RTcurrent) / (tcool x 0.8)

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