IMPLEMENTATION OF LEAN TOOLS IN AN SME

Transcription

1 IMPLEMENTATION OF LEAN TOOLS IN AN SME Hariram VR 1, V. Muthukumaran 2 1 Department of Mechanical Engineering, SNS College of Technology, Tamil Nadu , India 2 Department of Mechanical Engineering, Kumaraguru College of Technology, Tamil Nadu , India ABSTRACT This paper briefs the experience of implementation of basic lean tools in a medium scale foundry in India. Despite of the resistance offered towards change over basic feasible lean tools are implemented. Initially, the process timeline is studied followed by spotting of feasible windows improvement including layout change and 5S in the shop floor which are tracked through the current VSM. The future VSM with the improvements shows a considerable reduction in the lead time. This case study is presented to motivate practitioners to implement the basic lean tools in their SMEs. Introduction: In a developing country like India, where the customer market is more, industries and competitions are also more. Owing to the huge competition, companies and industries are in facing the sustainability issue. The prime reason being the quality and cost, Industries have no choice but to change their production systems. Lean on the other hand, sounds promising to address the issue. Also incorporating lean and green tools in the supply chain will help the industry to sustain. (Hariram Vedapatti Ranganathan 2012). (Gunasekharan.S 2015) suggested to develop independent industry specific models based on the need and constraints of the industry. But there are barriers for the industries to take up lean manufacturing methods instead of their conventional methods. (Diane Mollenkopf 2010) revealed the various drivers and barriers of the lean implementation in the industry. One such attempt is taken to implement lean in a medium scale foundry s supply chain. Lean tools: Lean manufacturing or lean production, often simply "lean", is a systematic method for the elimination of waste ( Mudu ) within a manufacturing system. Lean also takes into account waste created through overburden ("Muri") and waste created through unevenness in workloads ("Mura").Lean manufacturing is now one of the most powerful manufacturing systems in the world. Numerous plants around the world have attempted to implement or adopt it to enhance their efficiency. (James P. Womack 2003) Various Lean tools are available: 1. 5S 2. VSM 3. JIT 4. Pokayoke 5. SMED 6. Andon System 7. Kanban 8. Kaizen 9. Total Productive Maintenance (TPM) 10. One-Piece Flow 11. Work Flow Diagram etc. All of the above methods focus on identifying and reducing the waste that occurs in a process. 5 S: 5S is a systematic technique used by organizations comes from five Japanese words; Seiri (sort), Seiton (set in order), Seiso (shine), Seiketsu (standardize), and Shitsuke (sustain). Harsha Lingareddy etal. (2013) Impact Factor ( GIF) 5.42 Page 43

2 Vipulkumar C. Patel et al. proved that the implementation of 5S resulted in improved space utilization, safety of the employees, less scope of error, increased productivity, and improved inventory system, also increasing of machines efficiency, maintenance the cleanness of devices, maintenance and improvement of the machines efficiency, maintenance the clean workplace, easy to check, quick informing about damages (potential sources of damages), improvement of the work environment, elimination of the accidents reasons in the company. In addition, awareness of the 5S concept indirectly improved the morale of employees with better working environment (Vipulkumar C. Patel 2014). (HarshaLingareddy 2013) carried out a research involving the study and modification in the work place of a manufacturing industry in order to implement 5S. This strategy minimized the time of manufacturing in addition to the increase of the area of work place. The solution found by 5S approach solely minimizes several kinds of wastes in the production process and which finally helps in the development of the organization. An Inspection process has been executed on the basis of 5S check lists and the results analyzed to confirm great changes like increasing efficiency in production and quality, improves safety. VSM: The value stream mapping (VSM) is a visualization tool oriented to the Toyota version of lean manufacturing (Toyota Production System). It helps to understand and streamline work processes using the tools and techniques of lean manufacturing. The goal of VSM is to identify, demonstrate and decrease waste in the process. Waste being any activity that does not add value to the final product, often used to demonstrate and decrease the amount of waste in a manufacturing system. VSM can thus serve as a starting point to help management, engineers, production associates, schedulers, suppliers, and customers recognize waste and identify its causes. As a result, value stream mapping is a primarily a communication tool, but is also used as a strategic planning tool and a change management tool. Mapping out the activities in the manufacturing process with cycle times, down times, in process inventory, material moves, information flow paths, helps to visualize the current state of the process activities and guides towards the future desired state. In order to do this, the VSM visually maps the flow of materials and information from the time products come in the back door as a raw material, through all manufacturing process steps, and off the loading clock as finished products. The process usually includes the physical mapping of the current state while also focusing on where you get to, or the future state map, which can serve as the foundation for other lean improvement strategies. First the timeline was established and studied. Figure 1 Current Value Stream Mapping STEP BY STEP PROCESS : (Before implementation) wet core sand is taken for drying wet core sand is dried. (1 Hr) dry core sand has reached core shop.(15 Min) core sand has been mixed with oil and additives in the mixer.(25-30 min) core was made and allowed to dry.(25 min) core reached machining area.(15 min) moulding box is set to be made and arranged.(90 min) started to pour molten metal molten metal is poured.(45 min) taken to the knock out area and the finished product is taken out.(35 min) kept in shot blast machine and grinded for accuracy.(45 min) Impact Factor ( GIF) 5.42 Page 44

3 goes to painting section finished parts are painted.(1 hr) stored is dispatch area. The company plan is as follows. Improvements: Figure 2 Plan of the foundry After finding the drawbacks and timings, ways to reduce the wastage was done. The implemented ideas are as follows. Specific pathway were provided for the process of the manufacturing the product. The core sand drying area was changed from the gate area to the office area in order to save reasonable time while transferring the sand to the core shop. BEFORE AFTER Figure 3 Core sand area layout moved (before and after 5S implementation) Impact Factor ( GIF) 5.42 Page 45

4 BEFORE AFTER Figure 4 Additional core storage area (before and after 5S implementation) In machining area, the queue was formed owing to the placement of the two machines in the same area. So they were spitted the machining zones into two areas to reduce the waiting time by eliminating the queue. Figure 5 Machining area Impact Factor ( GIF) 5.42 Page 46

5 BEFORE AFTER Figure 6 Pattern Room STEP BY STEP PROCESS : (After implementation) wet core sand is taken for drying wet core sand is dried. (1 Hr) dry core sand has reached core shop.(12 Min) core sand has been mixed with oil and additives in the mixer.(25-30 min) core was made and allowed to dry.(25 min) core reached machining area.(10 min) moulding box is set to be made and arranged.(75-78 min) started to pour molten metal molten metal is poured.(45 min) taken to the knock out area and the finished product is taken out.(35 min) kept in shot blast machine and grinded for accuracy.(45 min) goes to painting section finished parts are painted.(1 hr) stored is dispatch area. After the implementations of 5S and Layout change, a considerable time reduction is noticed. Impact Factor ( GIF) 5.42 Page 47

6 map shows the impact of the 5S and layout change in the total lead time. The value stream Figure 7 Future Value Stream Map RESULTS AND DICSUSSION After implementing the 5S, Layout Change and VSM, it is evidential to see the considerable improvement in the lead time of the industry. Process improvisation Time taken before lean Implementation (Sec) Time taken after lean implementation (Sec) Time Saved (Sec) 5s in core shop s in pattern shop s in machining zone /box 5s in core sand transportation From the above table, we could see that a reasonable amount of time could be saved after implementing the manufacturing tools. Lead time Efficiency Increase = Lead time before Implementation - Lead time after Implementation Lead time before Implementation *100% = *100 % Lead time Efficiency Increase / lot = 5.128% By implementing lean manufacturing tools (5s and VSM), Found out bottlenecks. Differentiate value and non value added activities. Reduced the total lead time by 1360 seconds (approx.). Improved efficiency. References: 1. Diane Mollenkopf, Hannah Stolze, Wendy L. Tate, Monique Ueltschy. "Green, lean, and global supply chains." International Journal of Physical Distribution & Logistics Management, 2010: Gunasekharan.S, Elangovan.D, Hariram VR. "Strategic Approach towards Lean Industrial Transformation from Traditional Systems using Lean Industrial Model for Sustainability (LIMS)." International Journal of Mechanical Engineering and Information Technology, 2015: Impact Factor ( GIF) 5.42 Page 48

7 3. Hariram Vedapatti Ranganathan, Harishkumar Rajuvadan Premkumar. Improving Supply Chain Performance through Lean and Green: A study at Volvo group in India and Sweden. Master Thesis, Vasteras: Malardalen University, HarshaLingareddy, G.Sahitya Reddy, K.Jagadeshwar. "5S as a tool and strategy for improving the work place." International Journal of Advanced Engineering Technology 4, no. 2 ( 2013): James P. Womack, Daniel T. Jones. Lean Thinking: Banish Waste And Create Wealth In Your Corporation. London: Simon & Schuster UK Ltd, Vipulkumar C. Patel, Hemant Thakkar. "A Case Study: 5s Implementation in Ceramics Manufacturing Company." Bonfring International Journal of Industrial Engineering and Management Science 4, no. 3 (2014): Impact Factor ( GIF) 5.42 Page 49