Weighted Average Cycle TimeWhatever your cycle content, watch this average proxy’s back, and it’ll watch yours
Mon, 11/11/2013 - 13:05
Weighted average cycle time (Tcwa), also known as “average weighted cycle time,” provides a representative average cycle time (Tc) within a mixed model environment. Varied models or services in a given cell, line, or work area often have varied… Little’s LawA practical approach to patient wait time
Wed, 10/09/2013 - 11:58
Little’s Law, named after John D. C. Little and his 1960 queuing proof, characterizes the dynamic relationship between work-in-process inventory (WIP), throughput rate, and lead time within a reasonably stable system. The “system” can be that of a… Process Capacity Sheet MathHow to know if a process passes muster
Mon, 10/07/2013 - 11:01
The process capacity sheet, aka a table of production capacity by process, or production capacity chart, or process capacity table, is one of the three basic tools for establishing a standard operation. The other two tools are the standard work… Pull-System DesignBrief thoughts on sequence and math
Mon, 09/23/2013 - 16:42
From my experience, there are a handful of pull-system design steps. This column seeks to “simply” outline those steps and some of the math that should be considered. However, don’t let the brevity mislead you. It isn’t necessarily simple.
1.… Time Observation Form MathFor determining the lowest repeatable cycle time and the supporting-task times
Fri, 09/13/2013 - 09:48
The time observation form, also known as a process study form, is a basic and often-used tool for lean practitioners. Note that here we are talking about applying the continuous time-observation method and not the work-sampling method.
The form,… Work Content The focus is on the work and reflects the sum total work of <em>all</em> people in the process
Mon, 08/05/2013 - 16:40
Work content (Wc) represents total operator cycle time or, if multiple operators are involved, the sum of operator cycle times to perform a specific process(es) or subprocess(es). The scope of human work, including both value-added and nonvalue-… Pitch: Takt Image MathPitch should be matched to an organization’s capability to react to problems
Tue, 07/16/2013 - 09:44
Pitch is a representation of takt image—a visual and often audible management time frame that lean practitioners use to pace and monitor value stream performance. It’s typically driven by, and linked to, a value stream or line’s pacemaker process.… Value-Stream Map Lead TimeHow do you add up lead time from multiple processes?
Mon, 06/17/2013 - 12:27
Recently a reader posed the following value-stream mapping, lead time-related question(s). My experience, after facilitating more value-stream mapping activities than I care to remember, is that it’s not an uncommon question. In fact, it’s a very… Machine Cycle TimeMachines, too, run at their own rhythm
Thu, 05/30/2013 - 11:35
Machine cycle time (Tcm) represents the actual time it takes for one machine to complete all of its operations on one piece, product, patient, file, etc. It is applicable for both single-piece and batch processing. Unlike effective machine…
Every Part Every Interval (EPEI)The lean practitioner seeks to make EPEI as small as possible
Wed, 05/15/2013 - 12:10
Every part every interval, also known as EPEI or EPEx, represents the frequency that different parts are produced or services provided within a fixed repeating schedule. This fixed repeating schedule is often graphically portrayed, for training…
