As said by Henry Ford “Time waste differs from material waste in that there can be no salvage. The easiest of all wastes and the hardest to correct is the waste of time, because wasted time does not litter the floor like wasted material.” When we create an accurate, reliable and efficient system across all our production processes then the clients can be ensured for having the right products at the right time that are of good quality.
In lean manufacturing, the cycle time of a process is a basic element to match supply versus demand. It is the fastest repeatable time in which one part can be manufactured. Therefore, it is calculated as a time per part, and does not consist of damages such as collapses, faults, and additional postponements.
Difference Between Lead and Cycle Time
Cycle time (CT) can be considered as a more power-driven measure for the process proficiency. A different way to explain the difference is that CT measures the accomplishment speed. In order to decrease lead times the CT can and must be decreased. However, usually the time before the start of actual work is lengthy in reality so the waiting time must be decreased as well. By only changing the process alone we can control the time per cycle. The customers observe just the lead time as they hardly ever have access to the internal procedures. When an order is placed by a customer including internal as well as external to an organization, their main and only concern is the complete lead time which will be taken for delivering what has been ordered.
Calculating Cycle Time
Let’s suppose that the average cycle time is measured by excluding non-working hours as well as weekends. On the basis of the past data of our workflow, the estimates show that our usual cycle time comprises of 8 days. Now in case a customer places an order, their exact expectation of delivery time will be 8 days precisely. On the other hand, our cycle time is estimated just for working hours. In this case it means the delivery can be made after 12 days when the weekends are included as well. In the given scenario, the work will be completed according to our planned schedule from our point of view. However, the actual work will be delayed from the point of view of customers. In contrast, if the cycle time of our given tasks is calculated by counting non-working hours which also takes account of weekends, we will be in a better position to fulfill or even go beyond the expectations of our customers.
To calculate the measurement, divide value-added production time by total cycle time. This information can be used by an organization so that non-value-added activities can be removed. In this manner it is possible to decrease our costs and reduce the manufacturing time of our products. More to the point, both outcomes can become competitive advantages for our business, as we can lower the costs while sustaining good profits and providing quicker shift times to the customers as well.
It is important to bear in mind that the flow metrics are calculated from the viewpoint of customers. The customers are mainly concerned about the overall lapsed time. For cycle time, the Kanban calculation is very simple with that description:
Cycle Time = End Date – Start Date + 1
Now one might think how the “+ 1” is included in the above Kanban calculation. Basically it is added to represent those articles that are started and finished on the similar day. Let’s consider an example, if our work was started on December 15 and it was completed on the similar day, at that point it means 15 – 15 = 0. Nevertheless it cannot be said that an article took a cycle time of zero. Unquestionably, in the same way the customer would also never say anything like that. Rationally, that particular portion of work was not completed in zero days, but in a total duration of one day.