Q 333. What is cellular manufacturing? How does it help minimize the wastes in an organization?

 

 

Note for website visitors - Two questions are asked every week on this platform. One on Tuesday and the other on Friday.

• All questions so far can be seen here - https://www.benchmarksixsigma.com/forum/lean-six-sigma-business-excellence-questions/
• Please visit the forum home page at https://www.benchmarksixsigma.com/forum/ to respond to the latest question open till the next Tuesday/ Friday evening 5 PM as per Indian Standard Time. Questions launched on Tuesdays are open till Friday and questions launched on Friday are open till Tuesday. 
• The best answer is always shown at the top among responses and the author finds honorable mention in our Business Excellence dictionary at https://www.benchmarksixsigma.com/forum/business-excellence-dictionary-glossary/ along with the related term

Cellular manufacturing:- Cellular manufacturing is an automated & sequential set up of part by part (each part is manufactured in an unit called work cell) to get the final output (product). This manufacturing technique is very important concept of "lean manufacturing". 

 

The main idea of this technique is to set the manufacturing unit in such a way that all the steps involved in the manufacturing of the main unit will be performed step by step automatically.

Each work cell have its own software and hardware to achieve the part accurately, and to test the input came from the previous work cell to avoid defective output of the final products.

 

Usually this setup will be designed in U-shape, straight line or inverted U- Shape so that the monitoring of the process is much easy.

 

Advantages:-

 

1.   Mitigation of human errors by minimizing human interaction

2.  This will speed up the process

3.   Error detection is easy and poke - yoke can be designed to avoid the final output if their is any error amid the process hence the cost of rework of scrape is minimized.

 

Disadvantages:-

1. Initial set up is expensive

2. IT will take some attempts and corrections to achieve the final fine tuned, accurate & acceptable set up

 

Examples:-

1. Bottling, labeling & sealing  of beverages

2. Toys manufacturing

 

 

Cellular manufacturing in closed loop manufacturing or manufacturing in form of cell such as "U' ,"C"  or"O" shape of layout to minimize waste in process such backtracking of Man/Material etc. and make the process lean with lowest manufacturing cycle time. And also to improve Tac time of the process of manufacturing within the cell. 

                           The Single PC flow within the Cellular manufacturing process helps to reduce the inventory on the workstation to zero hence no waiting time for the processing job in flow manufacturing process Vs the standalone processing workstation.

Optimized the manpower by cellular manufacturing layout as single persons can work on multiple station by clubbing the activities as per process study will impact in reduction of manufacturing cost. 

  The Cellular layout ensure the pull manufacturing process so that the just in time can be implemented with the cellular manufacturing hence the raw material inventory can be drastically reduce and control with optimized processing cost per day.

The reduce raw material/ in-process  inventory will create space within the factory and also reduce or optimized space required for layout for cellular manufacturing vs  traditionally manufacturing.

  The saved space in today's environment can always be seen as opportunity for manufacturing expansion and improve on continuous basis. 

 

Tushar Ahire:- Student of Benchmark 6Sigma.

Reduce manufacturing cycles time
Reduce weighing time
Reduce transport cost
Reduce manpower
Improve quality

Cellular manufacturing consists of a series of product‐focused work groups (cells) which house all operations to manufacture a product family. The cell is devoted to manufacturing products which requires similar operations.
While during a traditional manufacturing environment is organized functionally with similar machines in one area (for example, all molding machines within the Molding Dept.), cellular manufacturing operates sort of a series of plants‐within‐a plant, each starting with raw materials and ending with finished product, with all operations being performed within the cell.
Machines in manufacturing cells are located within close proximity to take care of continuous flow with zero inventory b/w operations and to attenuate product transportation.
The cell is operated by multi‐skilled operators who have complete responsibility for delivery and quality performance within the cell.

 

 

Benefits of Cellular Manufacturing
• Cells shorten the space a neighborhood or product has got to move. This reduces handling costs, allows quicker feedback on potential quality problems, reduces Work‐In‐ Process inventories, permits easier scheduling, and reduces throughput time.
• Cells organize the materials location at the purpose of use to makes it easy to see the work ahead.
• Cell teams better understand the entire process of creating parts / assemblies.
• Cell members feel responsibility to a little group, instead of to an impersonal company. Understandable, logical participation results in a sense of empowerment.

4 Dimensions of Cells
Man : Operators are cross‐trained on support also as manufacturing equipment. Leaders and facilitators encourage teamwork, during a professional and fair manner.
Material : Materials management practices reduce work‐in‐process buffers. Material flow within the cell is streamlined to attenuate travel distances, and team members take full responsibility for quality of parts.
Machine : The layout of the cell permitting smooth material flow with minimum buffers, arranges equipment to be immediately adjacent.
Method : Procedures related to the cell help eliminate waste. The most apparent waste is flawed parts, so quality procedures detect any potential errors.

Limitations of Cellular Manufacturing
While its benefits are well documented, Some have argued that implementing cellular manufacturing could lead to decrease in manufacturing flexibility. Conversion to cells may cause loss in flexibility, which could impact the viability of cell use. Obtaining balance among cells is additionally harder than for flow or job shops. Flow shops have relatively fixed capacity, and job shops can draw from a pool of skilled labor so balance isn't that much of a drag . By contrast, with cells, if demand diminishes greatly, it's going to be necessary to interrupt up that cell and redistribute the equipment or reform the families.

Cellular Manufacturing: When we divide the entire manufacturing system into smaller groups or cells of machines, then it is called Cellular Manufacturing. It is an effective grouping of all the resources needed to produce a product. In order to improve coordination and allow everyone to see what is going on at all times, these tools, which typically include people, materials, devices, instruments and other production equipment, are organized in close proximity. The structure is much like that of a flow device, but it is more flexible. Normally, cells are laid out in a U-shape so that staff can move, load and unload parts from machine to machine. The Cellular Manufacturing also enhances team work within employees of different departments. Workers become multi-skilled and more adaptable to the business needs. Cellular processing is a tried and tested method that, while improving lead times, quality and efficiency, has lowered product costs. They work in almost every form of production environment.

 

One explanation why cells are efficient is that a lot of the waste inherent in a standard production process is always removed. Let's have a look at some of the waste:

 

1. Over Production: It means producing more than what can immediately be used by the next operation. By making it easier to manufacture just what is required, a production cell helps eliminate the waste of overproduction. Both activities are in close proximity, and it is simplified to balance the steps in the production process. One operator can complete several operations in a cellular arrangement, which can increase the balance of work and simplify product flow.

2. Excess Inventory: Excess inventory is a consequence of the waste of overproduction. It is also one of the most expensive wastes of all production. The problem of inventory waste is tackled by manufacturing cells in a variety of ways. Next, the work-in-process inventory is minimized by balancing the work and instructing operators not to surpass what the next individual can manage. Excess inventory can not be accepted by the design of the cell layout, because there is no place to put it. The vacant space paradox, which says the amount of vacant space is inversely proportional to the amount of time it is vacant, is resolved by manufacturing cells.

3. Over Processing: Another type of waste is to process a component more than is needed to make it work properly. Via near proximity of all processes and the technique of only producing what can be used, cells fix the waste of over-processing. As handling is reduced, unnecessary processes such as packing and unpacking are avoided and that which remains poses little risk of harm. Sections of the cells are processed sooner, so it is possible to remove some of the other product safety processes as well. The near proximity of all activities enables the detection of processes that do not add value to the product.

4. Motion: In a traditional manufacturing process, there is substantial wasted motion. This also results from a work area that is poorly structured. By bringing everything together in a production cell, it is possible to minimize, if not completely remove, wasteful motion. An obvious change is the removal of travel to other places to get pieces, but what can not be overlooked is the reduction of motion within an individual process. Motion shifts from non-value added to value added with a well planned cellular activity. Much wasteful movement is avoided as focus is placed on easily finding all operators need to do their work.

5. Defects: Defects are mostly the result of all the previously described waste, but they may also be the result of poor process management, poor product designs, poorly chosen equipment, and poor demand communication. Cells will not remove defects entirely, but they will allow for quicker detection of those that do exist, thus allowing for expedited corrective action. With close proximity to resources, defects are immediately communicated to all parties concerned, so no more than one defect at a time should be made.

6. Waiting Time: An unbalanced workload is one of the most frequent triggers of waiting. By promoting more coordinated flow, manufacturing cells will decrease waiting. Synchronized product flow is simpler with all the necessary resources clustered closely together. Worker versatility within the cell can also help minimize waiting time and when they are not busy, operators will assist others.

7. Order Tracking: While not widely accepted as a waste, order monitoring is very time-consuming and not a value-added process in production operations. Simplified scheduling is given by a production cell. As all tasks are grouped together, on a first-in-first-out basis, the order can be fed to the cell, and monitoring the status of orders becomes a visual search. In order to schedule the cell, complex computer systems are usually not needed. Many organizations use simple scheduling boards that can be used by the whole team.

Cellular manufacturing consists of a series of product‐focused work groups called “cells” which contains all operations to manufacture a family of products.
The cell is committed to manufacturing those products requiring similar operations. 
Role of Cellular Manufacturing in Minimizing waste
• Cells reduces the distance a part or product has to move.
It reduces materials handling costs, enables quicker response on potential quality problems, reduces Work In Process inventories, helps in easier scheduling, and reduces Lead time.
• Cells arrange the locating of materials at the point of use. This makes it easy to see the work ahead.
• Cell teams have Good Knowledge of the whole process of making parts/assemblies.

While all answers are correct, Subodh's answer clearly explains how cellular manufacturing can help eliminate wastes in an organization. Hence, his answer has been selected as the winning answer.