Machine telemetry terminal in the grinding shop.

Photos: IT Engineering

Planning in the office.

Planning on the production line.

Cheaper spring production

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Springs are used in a wide variety of industrial applications, from mechanical engineering to conveyor belts to cars. It was a problem with the throttle spring that lay behind Toyota’s recent recall of 2.3 million cars in America and 1.8 million in Europe, with all the attendant damage to its public image.
In order to become a fixture in a manufacturer’s supply chain, spring manufacturers need to prove their reliability. There are a number of organizational strategies that can help them achieve this. Many of these are built around highly detailed production planning; for example, Manufacturing Resource Planning (MRP II) is a method of structuring order and customer data in ERP systems. It allows theoretical advance planning, on the assumption that installed machine capacity will always be available, with no outages.
Other approaches simplify and speed up production. Lean production is about minimizing wastage. There should ideally be no gaps or pauses in the manufacturing process, so that throughput times are as short as possible. Lean production often goes hand in hand with the “just-in-time” strategy or kanban principles, both of which help to keep inventory levels down. As these different approaches are generally integrated, it is often hard to tell what impact each one has on production individually. Managers need to assess how feasible each one is in the context of their own business – generally speaking, only certain elements will be practicable.

Manufacturers might have to coil, grind, set, and quality-check small batches of springs one day, and enormous quantities the next. So they need to be set up for flexibility. Generally this involves a computerized ERP solution for financial and HR planning, including a production planning module. However, without adequate IT systems, production itself often remains something of a grey area for managers. Production lists are drawn up by working backwards from the scheduled delivery date. Managers will communicate this information to the production department, but there are often delays – machine capacity is often underutilized, and orders are often processed in a sequence that requires needless reconfiguration of machines. Managers can only check an order’s delivery status by looking at inventory levels in the ERP system.
The only way to get detailed information is to speak to the foreman on the production line. After all, he’s the person who always has to go through backlog lists and reallocate the work accordingly. On the ground, long-distance production planning often results in reactive fire-fighting. This means significant extra costs which cannot be passed on to customers. To keep to delivery dates, production of one batch often has to be interrupted, and machinery reconfigured more often than should be necessary. Many companies still make do with manually produced Excel tables and chats with production staff, rather than trusting in plant and enterprise data.

Simple IT solutions do not require expensive hardware upgrades and administrative support. Assuming machinery running costs of €50 an hour, and staffing costs of €15 an hour, the investment can pay for itself within a year, as a result of greater process efficiency. ERP software with the MRP II method may be useful for top-level long-distance project planning, but all these plans can be thrown out if a machine is offline or running at reduced capacity. However dedicated machine utilization planning software can counter this problem. This automatically plans capacity utilization at the individual machine level, on the basis of order information from the ERP system, and so speeds up order processing. Utilization plans for each machine are displayed in list form on terminals in the production department, and workers can see a list of current orders on their monitors. Meanwhile machine telemetry relays information back to the planning software, ensuring this takes into account the actual current situation. This is the set-up successfully used by Zimmermann Technische Federn GmbH in conjunction with the IT Engineering’s EMC system, enabling it to respond to urgent requests from customers.

IT is playing an increasing role in production. Along with customer satisfaction, levels of employee motivation are also a big factor in a company’s success. Giving staff the right IT systems can make their work less pressurized and show them the company values, so creating a more relaxed atmosphere, and a more productive, more profitable business. This automated solution also gives senior managers a better overview of the various processes within the production department, enabling them to see at all times where spare capacity is available, and how close to capacity each individual machine is. It identifies bottlenecks or potential problems meeting deadlines, and avoids the need to reconfigure machines several times. Companies are increasingly finding themselves having to deliver small quantities to tight deadlines, and if this is to be achieved, production operations simply have to have more and better data. Giving them this speeds up processes, cuts costs and ensures that springs are always available to customers who need them – and it results in profitable placed orders.

How much can an enterprise afford to spend on increasing productivity by 1% if that investment has to pay for itself within a year? This shows a sample calculation.
Assumptions:
– Machinery running costs per week: 3,200 Euro (40-hour week, two-shift pattern, 40 Euro/hour)
– Staffing costs per week: 300 Euro (15 Euro /hour, operating multiple machines)
– Total costs per year: 171,500 Euro (49 weeks)
Conclusions:
– Max. available funding per machine to increase productivity by 1%: 1,171.50 Euro (for ROI within one year)
– Max. available funding per machine to increase OEE by 1%: 2,450 Euro (for ROI within one year)

Founded in Pliezhausen, near Stuttgart, Germany, in 1995, IT Engineering develops software solutions to help manufacturing companies reduce costs by utilizing machine capacity more efficiently. EMC is IT Engineering’s user-friendly, integrated, modular manufacturing execution system that provides practical analytics. The company’s customers are primarily SMEs.