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If you are near a production or manufacturing line, here’s an easy and instructive exercise. Each time you’re on the line, stop for a minute or two and count the number of operators you see waiting.

Do this for a few days, take an average of your observations and express that as a percentage. Now you have an estimate of the potential productivity improvement that you’d see if only you enabled your employees to have something to work on all the time. There’s often opportunity beyond this simple view: in addition to the folks who are visibly waiting, many more line operators will have consciously or unconsciously slowed down to match their neighbor’s rate and avoid the need to stand and wait.

In my experience of dozens of implementations of this technique, companies have achieved productivity benefits ranging from 10% to 40%.

How can we eliminate waiting? Step 1: go to lunch.

Observe the local sandwich place (or burrito place, depending on your taste) at a busy lunchtime. The sandwich store I often go to is perennially understaffed – there are 4 places to work behind the counter, but never more than 3 staff. These 3 workers constantly move back and forth between workstations to keep sandwiches (and customers) moving towards the cash register. They have no room to let any more than 1 or 2 half-built sandwiches build up between workstations (and hungry customers would get peeved pretty quickly) so those sandwiches keep moving. As soon as the first sandwich-maker has one sandwich ready for the next station, he or she builds the next one and then moves downstream to the second station. Often, by the time he or she has worked on just one sandwich at the second station, it’s time to move back to station #1.

Note that all this movement is not directed by a manager, andon lights or anything sophisticated – other than the ever-present need to keep hungry customers (and their sandwiches) moving toward the register.

This same objective applies in manufacturing. With adequate line design, and a few simple tools, we can help line workers automatically move to always be in the best location to a) support customer demand, and b) be productive.

Visual Signals between Workstations

First, we need to establish a visual signal to tell operators when to move to a different workstation. This signal can be something as simple as a painted colored rectangle on the floor or production line between workstations. Often this visual signal is called an ‘In-Process-Kanban’ (IPK).

          Figure 1

In Figure 1 above, the IPKs are represented by a red square with an ‘X’. Each IPK holds one piece. 1-piece IPKs are common, but there are many instances where IPKs need to be larger to accommodate greater time imbalances between workstations (the calculation of IPK sizes is another topic – we’ll cover that separately). Whatever the size of the IPK, it represents a maximum quantity. When the IPK is full, and the next unit at the workstation is complete (i.e. the workstation is ‘full’), this provides a clear visual signal of a bottleneck.

Flex

In Figure 1, it’s quite clear that the line will not flow unless someone works at OP120. Operator B has the clear signal to flex into OP120, as shown in Figure 2.

       Figure 2

Another scenario is shown in Figure 3. Operator B has no product to work on, either in the workstation or in the upstream IPK. Clearly, the IPK signal is for Operator B to flex back upstream to OP110. Each operator will follow the signals like this all day.

       Figure 3

Sounds simple…

Operator flexing like this is pretty simple, until you reach a situation like the one shown in Figure 4. In this scenario, Operator B again has a signal to flex upstream to OP110 – but Operator A is working at OP110.        

       Figure 4

Here we have 2 options:

1. Aid and Assist. Operator B helps Operator A to work on the unit at OP110. This is often very feasible for large products. Even in machine-based environments, Operator B may be able to help by getting the next setup ready or loading material.
2. Bump. If not, then either Operator A or Operator B should flex out of OP110 and into OP100. Generally, the better choice would be Operator A as he/she would be more likely to be trained in this operation than would be Operator B. However, there may be exceptions and each line has to establish and document the flexing rules for these situations.

Outcomes

1. In well-trained and disciplined lines, productivity improvements from operator flexing typically exceed 10%.
2. Easier for line leaders to see issues in real-time. When IPKs fill up at a particular workstation, it clearly indicates a problem of some sort. For line leaders, this real-time indication is invaluable – we can be at the source of the problem while it is still occurring, not hours later when we see the results in end-of-line output.

Prerequisites

1. Cross-training. Operators should be trained in at least 3 operations, though more is better. Where operators cannot flex to a particular operation (for e.g. because of a lack of training, qualifications or work rules), the line generally needs larger IPKs and does not gain in productivity at that location.
2. Vacant workstations. A flexing line runs best when there are vacant workstations to flex into; the maximum productivity typically occurs when a line is 80% staffed (i.e. 20% of workstations are vacant).
3. Make it easy for the operators to flex. For example:
   1. IPKs clearly marked, with maximum quantities easy to see.
   2. Distances between workstations should be as short as possible
   3. Pathways between workstations should not be obstructed (inventory, walls, material, cabinets, machinery, conduit or piping)
   4. Tools, equipment and methods should be standardized (and not personalized) across workstations. Flexing is much easier to implement when operators perform work standing, not seated.
   5. Standard work exists – at least to the extent that the work at a workstation is clearly defined.
4. Training & Reinforcement. To state the obvious, flexing is a new skill for most people. It is important to train everyone in the new rules. I’d recommend posting diagrams of the different scenarios at every workstation, and provide a copy for everyone. To begin with, line leaders should spend at least 15 mins a couple times a shift just watching operator movement on the line… and provide positive feedback each day to each operator who is flexing correctly. Very importantly, a line leader should never walk past an overfilled IPK without investigating.

 

Operator flexing is one of the most significant productivity improvements available to most manufacturers without significant process change or automation. The best part – it utilizes your employees’ natural flexibility and ability to switch tasks rapidly.

 

For more information, visit us at www.praestoleansolutions.com , email at [email protected], or call at +1 720 891 2829

By Paul Boots, President Praesto Lean Solutions

 

Separate your fast and slow-moving orders to speed all orders to the customer faster.

Ever been stuck behind a slow-moving trailer or RV on a narrow mountain road with no place to pass? On a holiday weekend, the traffic may bottleneck back for a mile or more…

Imagine how your customers’ orders feel, being stuck in the same sort of traffic behind big, complex orders… and for them, it may be happening every single day.

If your orders or customer requests go through a significant order review, configuration, quoting or design process then read on. Here is a game-changing opportunity to create express lanes for your office-based order flow, and create a fast-moving flow of work through your order handling processes…

Complex vs Simple, Slow vs Fast

Your team members know that all orders are not the same. Some are complex and time-consuming while others are clean, straight-forward and quick. You can probably jot down a list right now of your typical complex orders, based on customers, products, $ value or markets (maybe even salespeople). Same thing for the really quick and simple order types.

At the same time, each of your team members likely has a queue of orders to be completed – sometimes small, sometimes large. Most of the lead-time for each order is tied up in those queues – typically orders spend 80% to 99% of their lead-time waiting in a queue. The easiest way to reduce lead-time is to reduce the queues.

Express Lane

You’ll see immediate, dramatic improvements in lead-time overall and especially for the more-standard orders by making a simple change:

–       Split your order processing team into two teams. One team for the ‘Complex Lane’, working on the slower-moving orders, and another team in the ‘Express Lane’ for the faster-moving, more-standard orders.

–       Do some calculations to get the staffing levels of each team as close as possible to the typical workload of complex vs standard orders. Don’t expect to get the calculations perfect. Where you have doubt, plan to err on the side of understaffing the express lane. If it gets overloaded, allow the overload to flow into the complex lane (this is much better than the other way round)

–       You may even be best served by creating 3 lanes (complex / medium / standard).

How does it work?

I’ve successfully applied this simple change in many environments over the years and the results are always dramatic. Why does it work so well?

–       The express-lane orders are no longer held up behind the big, slow-moving complex orders. It’s exactly the same thing you experience on that country road, or in the grocery store checkout line. Creating the express lane for fast-moving orders removes them from the slow-moving lane and enables them to flow much more smoothly with fewer bottlenecks.

–       Lead-time reductions for the express lane orders generally range from 50%-90%. On the complex side, those lumbering orders also experience lead-time reductions as their flow becomes steadier and more predictable. I typically see lead-time reductions of 10-30% for these orders. Since the volume of express-lane orders generally is much greater than complex orders, average order lead-time is greatly reduced.

Best candidates

Some environments will achieve greater improvements than others through utilizing this approach. If you fit these criteria, you have a great opportunity:

–       More than 4 individuals working on order processing

–       Time to complete a typical complex order is more than 2X a typical standard order

–       Team members can work all order types in the new lane structure (or can be trained to do so)

–       Orders can be readily identified at the start of the process as complex or standard.

Great start. Now what…

The creation of express and complex lanes is a game-changing move to reduce order lead-time. Once you begin this journey and pay attention to the flow of orders, you’ll undoubtedly identify more opportunities for further improvement in order lead-time and productivity.

 

Interested to learn more about how Praesto Lean Solutions addresses these issues – or how we can help your business? Contact us at [email protected] or call +1 720 891 2829.