Okuma factory investment underpins domestic manufacturing policy

Called Dream Site One (DS1), the new factory is located at Okuma's Oguchi complex, which is in Japan's Aichi Prefecture, whose capital is Nagoya. Construction commenced in August 2012 and involved demolishing an original manufacturing facility and erecting a new building 20% larger by floor area at a cost of ¥8 billion (£48 million), with the factory entering full production in May 2013. Image: Okuma has invested £48 milion in its new factory This investment and domestic Japan manufacturing thrust is driven by company president and CEO Yoshimaro Hanaki's belief that the Okuma's machine tool building skills, experience and tradition, which are deeply embedded in its 115-year history, reside in Aichi and Gifu prefectures and are not reproducible elsewhere. Encapsulating this culture is 'monozukuri' - the art of continuous improvement in making things through perfection in craftsmanship, backed by technology and processes that integrate development, procurement and production. And achieving this is only possible if manufacture of premium Japanese machine tools remains in Japan, in the view of Mr Hanaki. Image: president and CEO Yoshimaro Hanaki believes domestic manufacture is the way to further build on the culture of monozukuri Okuma's policy of domestic manufacture is in contrast to that of other large machine tool producers who build factories in different parts of the world to be near key global markets, reduce transportation costs and improve competitiveness, as shipping typically adds up to 8% to the cost of a machine tool. The new factory sees the introduction of lean manufacturing to allow it to compete more effectively with European producers of high added value machine tools. It will also help to combat the threat from emerging countries that take advantage of low wages, rather than efficiency to compete on price. The automated facility is capable of high efficiency machining of a large variety of components in low volumes, 24/7, followed by assembly of medium-to-large multi-tasking machines and lathes. It has doubled productivity and increased production capacity by 30% to 120 units per month, worth ¥3 billion (£18 million). Lead-times have been halved, shortening delivery times and enhancing customer service. Manufacturing costs have also been reduced, making the company more competitive, largely because the high level of unattended machining has allowed the headcount in the factory to be reduced by one-third. Said Mr Hanaki: "Provided that the world economy continues on its current path of steady recovery, I anticipate that DS2 and DS3 will be started in 2014 and completed within two years for assembly of larger and smaller size machines. "Additional investment of around ¥12 billion yen will be required to complete our Dream Site initiative in Oguchi, which is designed to streamline production of high added value products in Japan and cement our position at the top of global machine tool manufacture." At the Okuma Machine Fair, held at the company's Oguchi headquarters in November 2013, more than 6,000 national and international visitors saw 40 machines demonstrated, of which a quarter were new. The 23,600 m² DS1 site comprises a machine shop incorporating a spindle production area, linked to a just-in-time assembly hall, which includes inspection and shipment areas at the far end. Both main parts of the factory are temperature controlled. Between them are kitting and sub-assembly, as well as manual operations, such as hand scraping of slideways - a hallmark of Okuma products. Image: A view of the spindle assembly room at DS1, located in one corner of the machine shop Compared with traditional factory units, DS1 consumes 30% less power from the grid, as electricity is generated by banks of solar panels on the outside walls and roof. Use of LED lighting, wall insulation and other green measures contribute further to lowering the carbon footprint by 438 tonnes per year. Four lines of Okuma horizontal machining centres of various sizes, plus washing machines, form the centrepiece of the new machine shop. The production stations in each line are interlinked to form flexible manufacturing systems (FMS) using Finnish-built Fastems automated, multi-level storage and retrieval systems for machine pallets. The largest FMS, comprising double-column machining centres, is responsible for producing cast iron machine beds and bases, while the others are devoted to headstocks, saddles and columns. There is a cell served by robots for producing spindle components and housings for multi-tasking machines and vertical machining centres, and another cell for producing cylindrical grinder parts. Three Waldrich Coburg twin-head grinders have been imported from Germany and retrofitted with Okuma OSP controls for high precision machining of slideways, several at a time. Overall, 40 production units are employed in the factory, almost all having a high degree of automation. Image: A view down the large capacity, double-column machining centre FMS (left) in the machine shop at DS1. The Waldrich Coburg slideway grinders are pictured right. Image: One of the Waldrich Coburg twin-head slideway grinders at DS1 Extensive use is made of virtual modelling throughout DS1, from monitoring the order-driven production control system for prioritising work flow to simulating machining cycles for ensuring right-first-time metalcutting. The whole factory operates on the established, continuous quality improvement model known as PDCA, or plan-do-check-act. Large machines, such as double-column machining centres, as well as cylindrical and internal grinders, are produced in a separate complex nearby at Kani. It has five factory buildings totalling over 105,000 m2 and has also seen much improvement over recent years. Under Mr Hanaki's Global 70 strategy, it is Okuma's aim to increase the proportion of the machines it exports from its 63% current level to 70% in the next financial year. Europe and the USA are particular targets for growth, which currently consume 28% and 13% of output respectively, as well as China and emerging markets. Industry sectors expected to support the increase in export sales are aerospace (nearly 30,000 new aircraft worth US$4.4 trillion will be needed globally over the next 20 years), automotive, energy, infrastructure and medical, which is almost recession-proof due to ageing populations. Okuma claims to be the only single-source CNC machine tool manufacturer in the world: the machines, drives, motors, encoders, spindles and PC-based, open-architecture OSP control are all produced in-house. It differentiates the company from the competition and gives users confidence that all elements of a machine are perfectly complementary, without any compromises. CNC lathes represent 29% of turnover by value; machining centres account for 45% and include vertical, horizontal and double-column models. In the latter category, Okuma had nearly half of the domestic market this year, which is no mean feat, considering Japan is the world's second-largest machine tool manufacturing nation. The company is particularly strong in 5-axis CNC machining centres, with 10 new models introduced within the past 18 months. Multi-tasking turn-milling machines represent 21% of turnover and the company also produces grinders as well as wheel manufacturing and other specialised equipment. Two to 3% of turnover is invested annually in research and development, involving 200 people based mainly in Oguchi. It has resulted over the years in a multitude of innovative technologies, many of which have won international awards. The latest advance was the introduction in 2013 of an auto-tuning system for Okuma 5-axis vertical and horizontal machining centres and multi-tasking machines. It replaces the manual tuning process typically used to maintain motion accuracy involving complex mathematical calculations and manual data entry, which can take five hours or more. The 5-Axis Auto Tuning System performs measurements and compensation in real time and allows adjustments to be made in 10 minutes to compensate for geometric errors, without a high level of operator skill. The system automatically measures the machine and compensates for up to 13 geometric errors, including volumetric accuracy. Three other particular initiatives in Okuma's Intelligent Technology suite of performance-enhancing functionalities are: Thermo-Friendly Concept, introduced in the mid-2000s; advanced collision avoidance built into Okuma OSP control; and Machining Navi in the OSP control, which avoids chatter and consequent inaccuracies by choosing the optimal spindle speed. The Thermo-Friendly Concept sees symmetrical machine design and other measures eliminate the need for a temperature controlled machine tool environment. Top accuracy is maintained by restricting dimensional changes to within 8 micron over an 8°C temperature variation. Advanced collision avoidance is claimed as a market leader, in that it monitors - in real time - the entire machining area, including tool, holder, spindle, spindle head, component, fixture, slideways and guarding. Moreover it does this during an automatic machining cycle and, unusually, in manual mode as well. Machining Navi in the OSP control sees chatter detected by a factory-fitted sensor or retrofittable microphone in a machining centre, with the frequency analysed and settings to eradicate it displayed. They are applied either automatically or manually by the operator. For lathes, suppressing chatter requires a different approach, especially when turning at lower speeds. Automatic spindle speed variation within preset limits is the preferred method.