Productivity – A critical pillar of industrial competitiveness
Gautham Doshi, Advisor at IMTMA (Indian Machine Tool Manufacturers’ Association), talks about the importance of quality route in achieving productivity
Where does industrial competitiveness come from? Does it come from innovation? Sure it does! But is innovation enough to be competitive? Innovation is not the only ingredient for competitiveness, though it is a very essential or important one. There are countless cases where innovations have stayed in the cupboard and not commercialised. Does it come from industrial design? A good design converts an innovation into a product, which can be manufactured. However if not manufactured competitively there would be few buyers.
There is a saying “Selling coal to Newcastle”. Marketing people can sell anything to anyone. There is also another truth; one is successful and competitive if you have repeat customers. One can sell a shoddy product once but can one sell a shoddy or costly product to the same customer again and again? Finally success comes only when you have innovation, and a good industrial design competitively manufactured and effectively marketed.
Since we all agree manufacturing competitiveness is critical to success and productivity is a critical pillar, let us look at some facets of boosting productivity. The first thing that comes to mind is producing more components or parts in the same time or better asset utilisation. One way to do this is to reduce the cycle time of the process. However speeding up a process could lead to greater resource wear, for example cutting tool wear. In turn this could lead to a quality issue or a frequent change of tool and during which the machine would be idle. Thus one has to optimise the speed or cycle time and strike a balance between the parameters, which include the resource (tool) life. Continuous research in resources increases their life and at the same time allows one to operate at higher speeds. Needless to say the final limitation may come from the design of machines or the part being machined.
While optimising the cycle time is one facet, another important aspect to resource utilisation is how much time in a day or shift do we use it. We pay interest 24X7 but do we use our asset 24X7? For example if a cycle time for a part is 6 min, do we get 10 parts an hour or 240 parts in a day? If not we are not utilising the resource fully. The reasons for not getting 240 parts in a day are many, for example machine breakdown, set up change, tool change, adjustments of tool, lunch and tea breaks, material not available, electricity not available, operator not available and so on. All these result in poor resource utilisation. Often these reasons account for 60 per cent of 24X7 and are a very big drain on productivity.
In some organisations we produce for stock. For example we can produce 120 units of part A but we sell 100 units. 20 units are in stock to be sold in the next month. However in this period there was an order of 50 units of B and due to capacity constraints we were able to produce only 30 units of B. This is against common sense, but the reason given is we did not want to break the batch of A, because there is loss of productivity as an additional set up time is required. Machine utilisation is high but at the cost of inventory. What is forgotten is improper utilisation of resource, i.e. money. Therefore this is certainly not higher productivity. Often you can observe an operator of a CNC machine standing idle during the automatic cycle. Is this good resource utilisation? Resources include energy and material. Do our forgings or castings have too much machining allowance? What do we do to reach near net shape? Do we measure how much energy we consume per unit of our product and try to reduce it?
Larger batches are taken also because processes are not stable, rejection and rework take place. If one wants 100 to be dispatched take a batch of 105 could be the rationale. As a result there is waste in the process and poor productivity. Rejections mean that either the capability of the process does not meet specifications, or special causes make the process unstable. One needs to deep dive into the process and understand the variables that affect the process. SPC studies certainly help in analysing the process. Process control and monitoring systems need to be set up. A deep understanding of the process leads to its improvement and ultimately results in higher productivity. No rejections or rework mean one can produce exactly as much as one sells!
Value stream mapping is a very effective tool to identify steps in process, which do not add value. These activities that do not add value can then be eliminated, simplified, combined and overlapped, or reduced. Let us look at one such activity. A fixture needs to be aligned to the axis of the machine, whenever it is changed. During this period parts are not produced. Most engineers are aware of the several means available by which the fixture repeatedly gets aligned without loss of time. Another example; with the addition of pallet changer, cycle time permitting, machine need not be idle during lunch and tea breaks. Also load/ unload time for the part is constant and predictable. Autonomous maintenance carried out by operators has demonstrated in many factories a significant reduction in machine breakdowns. Workflow study often reveals excessive material and people movement. When traced in factories it often resembles a plate of spaghetti. Manufacturing system redesign results in smooth flow of material and people with shortest path. Newer and better processes can be included, which could not only lead to better productivity but improved quality as well. Assembly conveyors, wherever possible, with proper work station balancing are an example of optimising flow as well as minimising material and man movement.
In metal working new or better processes are continuously being introduced. New tool coatings and materials enhance cutting parameters as well as tool life. Hydroforming allows one to manufacture parts hitherto not possible or reduce the weight of conventional parts. New and better tool holding systems allow spindles to run at higher RPMs without reducing cutting forces. Newer CAM software using advanced cutting strategies allows one to remove material faster. Optimising design of machine elements using FEA tools allows one to make them more rigid and vibration resistant, allowing the use of higher cutting parameters. All these approaches lead to optimising metal working processes.Shop floor culture is a driving force behind improving productivity. It is observed companies that do not pay lip service to safety but give this aspect as the highest priority are also highly productive. A high level of safety cannot be achieved without practice of 5S. 5S needs complete involvement of all personnel. This attitude of mind will not brook poor quality in the workplace. One cannot have high productivity without high quality. They are totally intertwined. When quality improves productivity cannot be far behind. If a company takes up several Six Sigma projects, team members look deep into the process and find hidden treasures. Their understanding of the process improves and this leads to a quantum jump in productivity. High quality results in smooth and uninterrupted production and the best way to improve productivity. Sensible companies use the quality route to productivity. It also leads to less confrontation between management and workmen as no one has any issue with improving quality, especially when quality and safety are also closely linked.
There are many approaches to improve productivity. Be it through manufacturing system redesign, or better asset utilisation, or optimising the process or the quality route to productivity. Often companies combine all these approaches. There are many tools that one can use. TQM or the Japanese approach or the Lean approach of the western countries both look at productivity improvement maybe from slightly different view points, but the results sought are the same. Their approach is rooted in their culture. Maybe it is time for us to create an Indian approach rooted in our culture to improving productivity resulting in manufacturing competitiveness.
Gautham Doshi is the Advisor at IMTMA (Indian Machine Tool Manufacturers’ Association). On 7-8 December, IMTMA is going to organise Productivity Summit and Productivity Buzz in Bangalore. The event is a platform for helping manufacturing and production engineers to network, get acknowledged, and develop an Indian approach to productivity and quality. IMTMA has also announced IMTEX 2013 – 16th Indian Metal-cutting Machine Tool Exhibition with International Participation from 24 to 30 January 2013 at Bangalore International Exhibition Centre (BIEC) in Bangalore, India. IMTEX series is the largest exhibition of metal-cutting machine tools and manufacturing solutions in South and South-East Asia.