Material Flow Analysis: a simple approach

material flow analysis

Material Flow Analysis: a simple approach

Sometimes it’s the simpler improvement techniques that are the most effective. Material Flow Analysis is one such technique. In this blog I’ll outline the benefits of a simplified version and tell you a little about what’s involved.

Benefits of Material Flow Analysis

Material Flow Analysis is a very straight forward but effective way to improve efficiency whilst engaging your workforce. Any plant, regardless of product, can do it.

The purpose of Material Flow Analysis as I describe it here is to:

  • Reduce the number of non-value adding activities, such as moving material around the plant
  • Minimise handling damage
  • Reduce inventory
  • Decrease lead times
  • Improve customer deliveries and service

Furthermore, if material moves around the plant in a logical and efficient manner, it makes everyone’s job safer and easier.

The Material Flow Analysis Process

Material flow analysis has been around for a long time and there are many ways of doing it. Often the method involves creating a complex and detailed flow chart using different symbols to represent different types of activity.  These activities include operations, transportations, storage, delays and inspections. Sometimes ‘handling’ and ‘decision making’ can be included too.

However, the method I’m going to touch on here is much simpler. I have used it many times in aluminium extrusion plants, and I have been able to measure the impact it’s made. The best part is that you don’t need anything other than an Excel spreadsheet, some paper, pens and a small team. Your team should be a mixture of people from different departments, and include both shop floor and office personnel if possible.

There are many different flow paths within a plant, so the first thing to do is to analyse the different flow paths by volume.  You should choose the highest volume flow paths for analysis.  This ensures the improvements you make will have the greatest impact.

material flow analysis in extrusion plants

Figure 1. From extrusion billet to warehouse. How efficient is the material flow and can it be improved?

Capturing the current situation

First of all, you need to thoroughly examine the current material flow for the flow paths you’ve chosen. You can do this by breaking down the material flow into a sequence of activities. To keep it as simple as possible, you should describe each activity as either an Operation, a Transportation or Storage.

Every time the material moves, for example via a conveyor, crane or forklift, you should record it as a Transportation.  Whenever the material waits, and this could be in a designated storage area or in a queue for the next piece of equipment, you should record it as Storage. Everything else is an Operation.

By breaking the material flow down into these component parts, you can easily identify how you can make the flow more efficient.

To a flow analysis ‘purist’ this is an over-simplification. However, the aim is to get the team out onto the shop floor and questioning the status quo as quickly as possible using a method that everyone can understand.

Walking the shop floor

  • Working in pairs and starting at the beginning of the process, follow a unit of material through the plant to the shipping area. A unit of material might be a basket in an extrusion plant, a coil in a rolling plant or a box of components in a fabrication shop.
  • Record and measure EVERYTHING that happens to the unit on a log sheet. For an Operation you should record its duration (in minutes). For a Transportation you should record the distance travelled (in metres) and the time taken (in minutes). Finally, for Storage you should record the number of units and the average time spent waiting (in minutes).
  • You should also trace the unit’s path on a plant drawing to give you a visual representation of the material flow.

It’s very important to physically follow the material around the shop floor. This is because you must record what actually happens, as opposed to what you believe is supposed to happen!

material flow analysis

Figure 2. When analysing material flow, it’s important to physically follow a unit of material around the plant so you record what really happens (iStock.com/zdravkovic)

Making improvements to material flow

Often inefficient activities, such as moving a container from one storage area to another without any value-adding activity, become part of everyday life.  It usually takes an activity such as Material Flow Analysis to examine what is actually happening on the shop floor and to question it.

When examining a flow path it is important to think about every activity within it and to ask yourself these questions:

  • Why is this activity necessary?
  • Where should it be done?
  • When should it be done?
  • How is the best way to do it?

When trying to improve flow you should also consider the following:

  • Can you eliminate unnecessary activities?
  • Is it possible to safely combine activities?
  • Can you rearrange activities into a better sequence?
  • Can you simplify the activities?

A good example of combining activities is to pack straight from the line. If this is possible, you can eliminate several Transportations as well as some Storage. This is a popular solution for improving material flow in machine shops.

As you walk around the plant everyone in their pairs will see opportunities to improve the material flow. Therefore, it’s best to work as a group to discuss the various ideas before coming to a consensus. You could end up completely reorganising parts of the plant!

You can compare your ideas for an improved flow with your current situation by looking at the numbers of each activity and their measurements. The best way to do this is by transferring the information for the current situation and your improved situation to an Excel spreadsheet. You should update your plant drawing too. Now it’s time to arrange a trial.

Once you’ve made the improvements, it’s a good idea to repeat the analysis to verify the benefits and to look for further improvements to the flow.

Help with analysing your material flow

Although material flow analysis is a very simple exercise, it often works best when facilitated by one of our consultants.  We’ve done it many times before, plus we bring a fresh set of experienced eyes with us. We also have tools available to help with the recording and the analysis of material flow.

Usually after one 3-day workshop, your team will know the process well enough to repeat it themselves. If you’d like to know more, please get in touch.

(Thumbnail image: iStock.com/infografx)

Want to share this page?Share on Facebook0Tweet about this on Twitter0Share on LinkedIn9Share on Google+1

Helen Forrest

Helen’s areas of expertise are in the tools and techniques of Lean Manufacturing, knowledge management and marketing communications.

Back to top