SMED Implementation, Step - 4

SMED Implementation, Step - 4

"Improve internal changeover activities"

In my last blog on SMED implementation, Step -3,i.e."Convert internal setup activities to external setup activities" (in the link : SMED Implementation, Step - 3 ), methods are being discussed on converting internal setup activities to external setup activities with some changes in the process and thereby reducing the setup or changeover time. Now in this blog, we will talk about streamlining internal activities and thus achieving further reduction of setup or changeover time. 

One of the deliverables of Step 3 of SMED Implementation (i.e. - converting internal setup activities into external setup activities), is the final list of internal activities, that can not be converted to external work elements. Now, here at Step - 4 of SMED implementation, these remaining internal work elements are relooked and reviewed to be simplified and streamlined. For each of such internal work element the project execution team must raise following queries : 

1. How can the internal work element can be completed within lesser time ?

2. Will any kind of sequence change be helpful?

3. What are the complexities that needs to be simplified, while performing this activities?

As in the last blog of SMED Implementation, Step -3, we have spoken about cost versus benefit analysis to prioritize the work elements, upon which actions can be taken. Similar approach may be adopted for this step also to prioritize the actionable activities. 

Methods and techniques to streamline and simplify the internal activities :   

Shigeo Shingo, the father of SMED implementation technique once said that only the last turn of the bolt actually tightens it, the rest is just movements (or waste). Similarly there are various methods to simplify and streamline the work elements. Some of the techniques are detailed below : 

1. Quick attach and release mechanism :- Use of quick attach and release mechanisms (as detailed below) is one of the techniques to simplify the clamping and de-clamping  and thereby impacting on  the changeover time  - 

    a. Singular motion securing  : Attach and detach with single press as shown in the figure 1 below- 

Figure 1. Single Motion Securing

   b. U-Slot method of clamping and de-clamping : For faster clamping and de-clamping. This is as shown in figure 2, below -

Figure 2. U slot hole method of clamping and de clamping

      c. Pear Shaped hole method : For quick fixing and loosening , mounted on bolts, to have reduced time of overall changeover process as shown below on figure 3, below - 

Figure 3. Pear shaped holes on the base of fixture that reduces fixing and loosening time

2. Elimination of adjustments:- With a little innovative and out of the box thinking adjustment time can be reduced drastically or completely eliminated. A comparison of process flow is given below to give a clear understanding, in the figure 4.

Figure 4.Elimination of process adjustments and reducing the time consumed by internal work element.

Here the first process takes approximately 30 minutes to 45 minutes to get completed, with 2 to 5 adjustment cycles and on an average of 3 scrapped parts during each setup or changeover. Whereas the second process with a centering ball will have no adjustments and will have no rejections wasted for the sake of adjustments and will take a setup time of approximately 1 minute. Contribution of adjustment time in the total changeover or setup time is approximately more than 50%.An approximate elastration of the same is shown in the Pi -Chart (figure 5).

Figure 5. Distribution of time consumption by the work elements of changeover

So elimination of adjustments during setup will have a huge impact on reducing the total changeover time.

3. Eliminate motion losses : - To eliminate wastage during motion losses re organization of the workplace may be done as detailed below - 

     a. Simplification of the movements : - This can be done by following techniques - 

         (i) One touch - Keeping the tooling, jigs, fixtures and all other required items at one touch, i.e. the operator doesn't need to change positions and, with simple and easy hand movements, he is able to pick up the required tools, jigs and fixtures. 

          (ii) Usage of  short bolts - With shorter length (looking at the requirement), to reduce wastage due to multiple rotation.

     b. Parallel operations reduces setup time. Analyze the work elements of changeover and try to figure out the possibility of  making multiple internal activities parallel to each other.

    c. Elimination of bolting by using hydraulic, pneumatic or electronic quick clamping and de-clamping mechanism. Cam operated mechanisms for clamping is also widely used. 

4. Standardization of hardware's : - Standardization of tools are done so that very fewer and specific tools are used in the setup. While standardizing the tools we may focus on fewer aspects as relevant, like 

     - eliminating the need of hand tools, 

     - reduce or eliminate nuts and bolts,

     - usage of quick fastening and releasing devices 

There are many more methods, and while implementing, the project execution team must study, relevance, cost invested and benefits realized. After Improvement is done updating the essential documents like work instructions, standard operating processes, process failure mode and effect analysis, control plan, tool drawings, trial records must be updated. At the same time operator training also to be conducted on the updated procedure. All these activities will ensure sustainability of improvement. 

Deliverables of SMED Implementation Step 4 (i.e. Improve internal changeover activities) : 

1. Significantly reduced changeover time because of simplification and streamlining of internal work elements,

2. Updated and standardized list of tooling, jigs, fixtures and other required items,

3. Set of updated standards (like work instructions, standard operating processes, process failure mode and effect analysis, control plan, tool drawings).

I will explain the SMED implementation Step 5, i.e. "Improve external setup tasks" in my next blog (Link : Step 5 of SMED Implementation). 

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