Q. 108  Changeover is a constant across all domains and industries. The time spent in changeover from one product to another or from one service to another is a loss of productive time. Single Minute Exchange of Die (SMED) is a powerful Lean tool that helps in reducing the time loss during changeovers. Highlight the key steps involved in SMED using relevant examples. 

 

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SMED (Single Minute Exchange Of Die)

 

SMED is a systematically proven improvement Lean methodology - improvement in terms of time and cost depending on the way it has been implemented. Ideally there are two generic approaches to achieve the goal with this

 Human ( Achieved through People and organization )

Technical ( Achieved through Technology)-  Automation , RPA, AI ( on the broader perspective)

 

The change in SMED comes as many as changeover steps involved as "external" and try to identify them as wastes in the process and ultimately removing these from the system or process. SMED process improvement methodology started in the Industrial manner with Shigeo Shingo, a Japanese Engineer with the effort of removing huge wasteful steps in the manufacturing industry and thus provide lower manufacturing cost and improved deliverables thus an increase in Customer demand which led to more production.

 

The basic steps involved in a SMED structured approach are:

 

1) Identification of the Plot Area where a particular work is being carried out

•       What work is done, how it is done, applications, products, equipment used
•       People, culture, Duration, environment
•       Risks involved, variation , Opportunities

2)  Identification of the elements in the Plot Area

•         Description of the problem identified
•         Technology required ?
•         Cost in time (Estimated)

3)  Separate the External Elements from the Internal Elements

•        Elimination of the External element identified
•        Any inspection, retrieval, cleaning , re-structuring

4) Streamline the remaining Internal Elements

•      Cost measured by Technology or Manpower needed to make necessary changes
•      Benefit in time
•      Establishment of the new process and continuing with the enhancement of the change.

 

Please feel free to suggest your thought processes and ideas.

Regards,

Somrita

       

 

 

 

 

 

Wiki Definition: Die is a tool used in manufacturing industries to cut or shape a material

 

SMED: It is a very important lean technique/method for reducing waste in a manufacturing process . It helps in a quick change over in a process from running the current product to running the next product. 

 

Let me provide some examples on SMED with focus on changeover. 

Examples on SMED : 

1. Imagine there is a process which has two kind of bolts used - T-bolt and General. Depending on the situation, the tool bit can use either T-bolt or General bolt. How quickly the changeover from T-bolt to General bolt happens is the key

2. Imagine , there is a startup Small-sized company. There is a PaintBooth. For a product - two different colours are needed. The Spraying tool is filled with Blue. Then Green has to be filled with in that . How quick that changeover can happen.

 

As far as with my constrained knowledge on this , i believe below are some crucial steps in SMED:

Steps involved in SMED:
1. Identify the area for improvement
2. Decide on how to go about
 - Reflect upon/Decide the no of parts reduction in the assembly kit, if applicable 
 - Work on the Tools Design Modification, if applicable

 

Benefits of SMED:
1. Reduced Cost
2. Improved Process
3. Meeting Customer Demands

 

Conclusion:

SMED is very vital, especially to manufacturing industries. If the Die or tool bit is defined or better aligned to the needs, then changeover can happen seamlessly, which can eliminate the waste involved in the whole process.  Classic example you can always think of is the changing of tyres under normal circumstances by a person and changing of tyres in F1 Car Races by the staffs of a Racing team.   

SMED technique is one of the powerful lean tools which is widely used for Reducing changeover within 10 min both in Manufacturing or non-manufacturing. It helps to enhance the available time of the machine thereby increase OEE significantly. The following are the key steps involved in SMED

 

1. Conduct video workshop( select & record the changeover time which is taking more time) - Conduct time study for at least 5 changeovers for accurate changeover data.

 

If Changeover time is taking product A to product B is X hrs. but the frequency is 2 times/ shift & Product B to Product C it is consuming X+ hrs. & frequency is 3 times/ week. It is better to select the former one(A to B)since the frequency of changeover is high compared to latter.

 

2.  Carry out video analysis to separate internal & external activities ) Internal activities are which to be carrying out when the machine is stopped & external activities are those which can be carried out when the machine is running. This helps to analyze the loss of productive time which is also termed as Loss analysis.

Some of the examples of internal activities are Removing old die & fixing new die, resetting machine parameters like speed, feed etc & some of the examples of external activities are preparation of jigs & fixtures ready with suitable product material, keeping ready tools &tackles to eliminate search & find( some ineffective therbligs during changeover)

 

3. Convert internal activities into External activities as much as possible through ECRS (Eliminate, combine, Rearrange & Simplify) analysis to reduce the internal setup time& thereby reduce the work while machine stoppage

 

4. Eliminate/ reduce internal setup time. By taking the support of updating technology, we can eliminate/ reduce internal setup time like reducing screw fixing by tool by wing nut etc. & eliminating manual conveyor adjustments by automated adjustable conveyors etc.)

 

5. Eliminate/ reduce external setup. Whatever the activities are performing while the machine is stopped, that should be reduced which indirectly effect in reducing internal setup time. Getting material during the changeover (even though short notice demand), 2 S practice( A place for everything & Everything in its place)  for every changeover.

 

6. Streamlining the activities by updating method instructions, providing awareness training on F1 culture followed by SMED workshop on new tool & tackles to each & every operators.

 

7. Carryout Cost-effective analysis to obtain actual benefits by eliminating changeover. For this, it is mandated to prepare Kaizen sheet for each & every improvement(both tangible & intangible) & it should be verified by CFT team( Maintenance, Quality & other related departments) & approved by plant head as well as Finance head. The kaizen sheets should be converted into OPL(one point lesson) & display at the machine for deskilling management. Visual controls can be useful to give an entire idea to operators/ supervisors about implemented kaizens.

 

Sometimes, it will require customer approval of every kaizen to see the impact of quality on the final product.

 

The three analysis namely Loss analysis, ECRS analysis & cost-benefit analysis are mandated & it gives you clear scope & target to fix future target to reduce changeover from SMED to OTED(One touch exchange of die-  reduction of changeover time by 100sec)

 

 

SMED concept is given by Shigeo Shingo's and is a lean technique which is used for reducing the setup or change over time at the factory process.As the name reflecting, Single Minute Exchange of Die aims to reduce setup time to single minutes or less in other words we can say that changeover time should be less than 10 minutes.

SMED has been developed within Toyota Production System(TPS). Initially in starting of industries, hours of time taken for change over.The most common example of change over we can see changing of tire. If we see formula one racing car, PIT has reduced their tire change time form 15 minutes to 15 seconds or even less than this. Ferraro has achieved it even less than five seconds. SMED is all about to remove all wasteful steps in the changeover process.

SMED needed at shop floor because if changeover times consumes many hours and we try to get maximum output from these machines by minimizing the non value adding activity or changeover. if we are going to produce smaller batches then there is need to reduce changeover time.

The main aim of SMED is to reduce setup time and it works and it plays a very important role to run JIT and KANBAN properly at shop floor. SMED has following benifits:

• SMED can reduce handling equipment loss by turning it to automatic operation.
• Lead time can be reduced 
• Can increase capacity of line
• Can improve quality
• Helps to produce a variety of products in short span of time
• Shop floor space utilization properly 
• Can reduce scrap quantity

While implementing SMED at shop floor , following steps are followed :

1. Differentiate and separate both internal & external activities while setup
2. Standardization of external setup activities
3. Conversion of internal to external setup activities 
4. Continuous improvement in internal changeover activities
5. Continuous improvement in external changeover activities
6. Autonomation setup
7. Elimination of changeover 

After implementation of above seven steps, we can see improvement in changeover time and it can be standardize further to be effective and to use properly for other team member and further take a goal to reduce more and improve the productivity.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I will give example of services industry, when in a contact center you keep on receiving call after call and need to minimize the time it takes for one agent to log off and another agent to login. We defined a set of instructions to follow... 

1- Wrap up the current call, while explaining the rating process, initiate computer log off. 

2- while transferring call for quality check complex system log off... 

3- disconnect call and log off from telephone system

4- Next agent initiates system login, 

5- while system log the user in, connects headset and logins to the telephone system using their code. 

6- ready to receive the call. 

 

Using this stepwise method we reduced the avg handover time from 6 mins to 2.5 mins 

SMED – Single Minute Exchange of Die, basically, in literal meaning, aims at reducing the processing of end product/service within 10 mts or in a single minute range. This also applicable where the processing time cut downs to half, say from one hour to 30 mts. This requires clear understanding of where productive time is lost and decisions on improvement initiatives are made based on hard data.

 

The major steps involved in SMED are:

 

1. Identify the process – identify the process where we would like to implement the changeover. The process could be selected based on the historical data, been a lot of variance in the process/service, and the operations are frequent in nature and the relevant employees are familiar and trained for the process changeover. The process should have room for improvement.

2. Identify the elements – Analysing of the current process, step by step, would give insight for where the improvement is feasible.

3. Separate External Elements – All elements of operations to be segregated into internal and external – Internal activities represents activities which only can be done when the process is not running – External activities implies those activities which can be performed even when the process is running.

4. Convert Internal to External Elements – To gain time and improvement, focus should be converting as much as possible internal elements to external elements.

5. Streamline or Standardization – Once changeover process is implemented and gain realized from the pilot project, standardize the approach across all similar processes.

 

Let see few examples.

 

The universal example for the Changeover is Pit Stop, where the Pit Crew changes the 4 tires in 15 seconds in comparison to many people taking 15 mts to change a single tyre. This is achieved through performing many steps as much as possible before the Pit Stop begins (keeping sufficient tires, fuel, and equipment & tools ready) and also using a co-ordinated team to perform multiple steps in parallel, creating a standardized and highly optimized process.

 

In a day to day operation, let’s see example of Air Craft cleaning after the passenger trip. Initially, it uses to take an hour to clean the whole air craft to keep it ready for the next operation/flight immediately. With the changeover techniques in place, like, passengers are educated and advised to deposit of their waste and used materials, in dustbin bags being carried by the airline staff. This majorly avoids the time and effort, in collecting the waste being kept at each seat traditionally, after the flight lands. With this improvement, the cleaning staff has to collect the dustbin bags and fast clean the aircraft to keep the flight ready within 30 mts for the next trip/operation.

 

In BPO industry where with the help of technology advancement, changeover technique can be implemented, as per the appended example mentioned.

 

For Static data capturing, the process involves, capturing of similar and same data for each application by two different employees, to compare and reduce room for errors, which would be monitored and rectified by the third person as error proofing and keep the correct data from each employee for the application process.

 

To improve the process, both quality and time, we can introduce OCR (optical character recognition) or ICR (intelligent character recognition) techniques to read the applications and plot the relevant data at appropriate boxes in the tool/system. This way, the process would be extremely fast, accurate and can eliminate two process steps (2 processors capturing the same form) and improve the quality check/accuracy.

 

Conclusion: To implement the changeover, one need to analyse the process, area for improvement, how beneficial be the changeover with respect to cost and benefit, revenue generation, time and productivity improvement.

SMED changeovers to be performed as below.

1. Select a changeover process for the study - bottle neck process (based on internal or customer oriented priorities)

2. Videotape the entire activity of current changeover process - approved video camera is preferred (with permission)

3. Document the current changeover process - Please use a element tracker sheet for observation/recording the facts

4. Display the video & analyze the entire activity of changeover processes - Record the internal & external elements and associated time for detailed understanding - Generally 40 mins video analysis takes 15-18 hrs for understanding

5. Identify the total no of activities for the 40 mins & then Re-design the changeover process based on the critical elements - Process involves converting internal elements to external & Sequential elements to parallel elements - Standardize the equipment & tooling, move to one touch attachments/bolts/interlocking grooves/fixtures/clamps, eliminate adjustments - Recommended to use ECRS approach (eliminate, combine, re-arrange & simplify)

6. Prepare Improvement actions list with responsibility/target time for implementation - Implement & Improve the changeover process

7. Compare the before vs after improvement for monitoring purpose & for any corrections/value additions - Changeover time should ideally be less than 10 minutes (Singe fraction minute exchange of dies)

8. Standardize the process for further improvement & horizontal deployment on similar process across the organization

9. Appreciate the team with rewards & recognition for further promotion of SMED initiatives across organization

 

Suitable examples are working with a pit crew in racing team, Quick changeover for machine stoppage in production line, SMED oriented stamping process changeovers etc

Changeover time is the time that is required to do certain set-up change before starting a different set of operation.

 

With SMED technique , we can reduce the waste in an efficient way by converting a manufacturing process for one product to next product.

 

Steps involved in SMED are as follows

 

1.       Calculate total time required to perform the task.

2.       Identify Internal and external tasks. Identify the external task which can be performed parallelly when the equipment is running

3.       Identify internal task which can be converted to external task.

4.       Eliminate the internal waste

5.       Eliminate the external waste

6.       Standardize

 

 

Example:   In a car manufacturing company ,  dashboard assembly is a major activity that was initially done as a main process. Over the period of time,  dashboard assembly was defined as an external activity. With this SMED Technique when the main assembly is in process, dashboard assembly was performed as a sub assembly, which reduces the car manufacturing time.

 

Khalandar's answer provides the detailed steps followed for SMED. It is the chosen best answer. Chella's answer provides multiple examples from various industries and adds to the clarity on the topic. Chella's answer also provides application orientation for the concept in the service industry.