A number of customers asked that I come up with a sample excel sheet for cycle time analysis. In response, I've decided to include two sample sheets: The first allows you to track cycle times within a given work cell by accounting for set-up times and capturing the causes of work stoppages within a notes section. This first sheet is ideal for short production runs because it allows you to account for those set-up times in your overall cycle time analysis.
The second is meant for larger production runs, ones where a single set-up time isn't a concern due to the size of the batch quantities. The second sheet allows you to graph these cycle times in order to better understand the variances in times from one shift to the next, or from one work cell to the next.
Cycle Times Must be Analyzed in Person
Before going into these sample excel sheets, it’s important to understand one critical point: A Manufacturing Resource Planning (MRP) software can only show you what the cycle times are in a given work cell; the software can't show you what the cycle times should be. These systems are meant as tools and they are only as good as you allow them to be.
Instead of just taking the information from your system, it's important to start questioning why your cycle times are what they are. There is no software intuitive enough anywhere in the world to tell you what your cycle times should be. You have to determine those times for yourself. Once you do, you can then track that benchmark cycle time and all the variances against it.
First, determine what your ideal time is in a given work cell - without any downtime whatsoever. Second, track your variances against these ideal times. However, it's not about achieving these times on every operation. Instead, it's about trying to reach that ideal time as often as possible by continually eliminating downtime and all its causes.
The First Sample Excel Sheet for Cycle Time Analysis
This first sheet allows you to capture the root causes of downtime in a given work cell within the notes section, while also allowing you to account for your set-up times for a given work-order or batch. Production set-up times play a pivotal role in cycle time analysis for small production runs as that time must be divided by the number of operations needed to complete a given work order. A company with short production runs must account for its set-up times within its overall cycle time analysis.
All you need to do is account for your original set-up time and individual cycle times while writing down the root causes of work stoppages. The sheet will add up all the times, include the total set-up time, and then divide the total by the number of operations. This will give you a true indication of the times emerging from this cell. Here is the first sheet: Here is the first sheet (below): Download Cycle-time-sheet
The Second Excel Sheet: Tracking Cycle Times and Variances
This second excel sheet is more for larger production runs, ones where set-up times aren't a concern simply due to the large volume of operations being performed on a single work order. This sheet below is from the article: Cycle Time Tracking & Variance Analysis in Excel for Small Manufacturers. This sheet is for those who want to track their cycle time variances and graph them in order to pinpoint high and low cycle times. It allows you to figure out your mean (average like the first sheet above), your median, and your mode times from a given cell or work station.
The mean, mode and median are just different methods of calculating average. However, the mode time is the one that occurs the most often in the sequence, and it is often the one associated with the least amount of downtime. Here is the second excel sheet: Download Cycle Time Tracking Variance Analysis in Excel
I’ve tried to make these sample excel sheets easy to use. Ultimately, success comes down to tracking each individual cycle time as it occurs and repeating the process over several days and shifts. In this case, it's a continuous process, one where you assess the times in an individual work cell, reduce them and then assess those times again at a later date with the same process.
Be sure to account for your initial set-up times if your company does short production runs with small batch quantities. If your company has large production runs, then the second sheet is likely your best option.
In the end, reducing cycle times comes down to isolating the causes of work stoppages. There are multiple strategies to accomplishing the same goal. However, it really comes down to understanding why downtime occurs and systematically reducing its long-term effects.
Learn about proper work cell layout and design.
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