Line Cycle Times
Once Products have been added to a site, now Line Cycle Times can be defined. Line Cycle Times represent the time needed, in seconds, to produce a single unit of particular Product on a Specific line., and are used to set the Demand in the pitch boards as well as to display the estimated order total time in the Order and eKanban Planning screens. Some Lines may run the same cycle time for various products, in which case a default Line Cycle Time can be set for all Products on that Line by leaving the Product dropdown empty in the Line Cycle Time details screen.
The Planning Rate is used to accommodate known productivity losses by dividing the Cycle Time by the Planning Rate to come up with a more 'realistic' Cycle Time to be used for setting Demand and determining total order production time.
- E.g. If the Cycle time for a product is set to 60 seconds to make a single part but consistent downtime issues prevent parts from being made every 60 seconds, applying a Planning Rate of 75% will mean a Cycle Time of 80 seconds (60/0.75) will be used for calculating Demand.
An important note is that Planning Rates should only be applied when Cycle Times are not based on observational data but theoretical line performance. Observation-based Cycle Times already have built-in Planning Rates because they are typically captured by watching a Line produce a Product over a period of time, when there may be machine or other stoppages, and then calculating an average Cycle Time. Therefore, applying another Planning Rate on top of this Cycle Time is doubly accounting for possible productivity losses.
Maximum Quantity Produced Per Pitch
This setting defines the greatest Actual quantity that is acceptable for single pitch wherein the subject Product is produced on the subject Line. Leveraging this setting can be useful for identifying errors in documenting Pitch Actuals, especially if they are entered manually, when used in combination with the setting Set individual pitches red if the actual exceeds the Maximum Quantity Produced Per Pitch setting in the Line Cycle Time. In this case, it may be helpful to incorporate some buffer quantity in case Actuals are not capturing precisely at the pitch end.
- E.g. If the Line is not physically capable of producing more than 1000 units of product in a pitch span, a value of 1000 is entered in this field.
Cycle Times per Operator Count
When using this functionality, it is important to note how the system selects which Cycle Time to apply based on the number of operators checked in to the Line or cell.
The order the system searches for Cycle Times is as follows:
- The exact number of users with a Cycle Time that matches the Product
- The next lowest number of users with a Cycle Time that matches the Product
- The next highest number of users with a Cycle Time that matches the Product
- The exact number of users for the Line's default Cycle Times
- The next lowest number of users for the Line's default Cycle Times
- The next highest number of users for the Line's default Cycle Times
- E.g. If cycle times are established for 3 and 5 users for Product A on Line B, and 4 users check into Line B which is running Product A, L2L will use the cycle time for 3 users. If 2 operators check in, it will use the cycle time for 3 users.
When a pitch has a fractional operator count, the greatest operator count value that is smaller than the actual operator count is used for calculating OEE.
- E.g. there are 3.5 users during a pitch, it will use the cycle time for 3 in the prior example.
Defining Cycle Times for Desired Performance Calculations
Some important considerations must be made when entering Cycle Time values, depending the desired approach for calculating certain performance measures.
To calculate certain Production Statistics, L2L defines an "ideal cycle time" value for each pitch. The "ideal cycle time" is pulled from the Line Cycle Time list for the subject Product and Line according to the current product and the current operator count for the pitch. This value is then used in calculations for the following metrics, without applying any Planning Rate that may also be listed for the subject Product and Line:
- Theoretical Efficiency (TEFF)
- Performance Per Part (PPP)
- Overall Equipment Effectiveness (OEE)
- Target Quantity column
It is important to understand how this ideal cycle time is determined and where it is used for multiple reasons when establishing Line Cycle Times in L2L. If an organization expects OEE and the other metrics mentioned above to 'purely' represent how a line is performing against its theoretical engineering capability, then only a single set of data for Operator Count and Cycle Time should be defined for each combination of Line and Product. Furthermore, this Cycle Time should be equivalent to the desired "ideal cycle time", which plants might refer to internally as the Engineering Rate, Ideal Run Rate, Theoretical Rate, Maximum Cycle Time, etc. Otherwise, L2L could leverage any of the multiple listed Cycle Times as the "ideal cycle time" for calculations, dependent on Operator Count.