Machine tool outsourcing delivers OEE of 85 per cent, or more
Machine tool outsourcing delivers OEE of 85 per cent, or more
Keywords: Aircraft components, Machine tools, Production engineering
Machine tool maintenance is one area that has been largely overlooked in the general trend towards contracting out in industry. However, it is an area where the problems of skills shortages, spares availability for diverse machine stock and stiff OEE targets mean that specialist help is particularly apposite ... but to what degree? Bill Wright, commercial manager of the Deritend Group attempts to answer this question and provide an economic justification for a service that places an enormous amount of trust in the provider.
Machine tools are the lifeblood of any engineering concern, and their care and maintenance are crucial in ensuring continuous levels of production to meet both OEE and productivity targets. However, for the companies concerned, keeping their machine stock properly maintained is becoming an increasing problem.
The first reason why this is so is the skills shortage plaguing British industry. There are just not enough trained fitters and maintenance engineers to go round; and finding and keeping staff with the necessary electrical and mechanical skills to maintain large and diverse concentrations of machine stock is becoming almost impossible.
Moreover, even if companies are able to harness the skill levels required,they are unlikely to be able to deploy them on a 24/7 basis
Compounding the skills shortage is the requirement to hold large asset values in the shape of machine tool spares. Answering the question of what levels of spares should be held by a manufacturing organisation is always difficult;keeping large amounts of cash tied up in spares is not an efficient use of capital for any business. However, try telling this to the engineer who is charged with achieving a target level of OEE in an intensive manufacturing environment.
Of course achieving a set level of OEE is one thing; but how do companies go about increasing it to improve competitiveness in the face of the skills shortages previously mentioned? To get improvements, operators need to be trained more effectively to look after their machines. In addition, there is the question of the addition of new machine stock. The way that this is integrated can have a profound effect on OEE; it can also consume the time of an existing maintenance resource completely during installation and commissioning. Companies can, of course, rely on the OEM machine builder, but this is not a service that will encompass the whole machine stock, rather it is product- focussed on what has been supplied. In addition, experience shows that relying on OEMs for post-machine servicing and support is an expensive and limited exercise at best.
So how are these problems overcome with outsourcing? Well, with a business that is totally dedicated to machine tool maintenance, skills are directed to that resource. Deritend, for example, has 220 skilled engineers trained in both mechanical and electrical disciplines, providing a resource that is available to companies not only 24-hours a day, 7- days a week, but also 365-days a year. What the specialist provides is a single source responsibility for both mechanical and electrical operations across all types of machine tools,something which no manufacturing company – or OEM – can provide on their own. However, this does not mean that in-house skills are ignored; in fact they are preserved as Deritend integrates all existing machine tool engineering personnel into its outsourcing operation. These engineers then bolster a resource that provides guaranteed levels of service and performance. They also become part of Deritend's answer to the skills issue: all company personnel being targeted to improve their skills levels by at least 10 per cent per year.
The provision of necessary skills is only one facet of outsourcing, however. The overall procedure as employed by Deritend starts with an audit of company's machine stock. The purpose of this audit is to identify key equipment in the production process, with the objective of determining risk. The method used is the RAG system: red, amber and green, with red – designated machines being the most crucial to production, Amber the second most important, and so on.
The areas of risk identified are highlighted in a report prepared for the client. The report also contains recommendations as to what level of planned preventative maintenance is required, and its frequency, and identifies which parts are likely to cause problems and what lead times apply to these critical parts. Once these are agreed, Deritend undertakes to hold the spares centrally on a 24/7 basis.
Identifying and cataloguing areas of risk is all important for the next and most important phase of the outsourcing process: determining an agreed OEE level with the client. For the client outsourcing is a big step, but one which is largely mitigated when a guaranteed OEE figure is provided. The OEE target is agreed between Deritend and its client, and is based upon a number of factors,including customer efficiency, plant availability, utilisation and defect ratios. Taking all these factors in consideration, Deritend regularly achieves OEE of 85 per cent (Plate 3).
Plate 3Machine tool outsourcing delivers OEE of 85 per cent, or more, taking into account plant availability, utilisation and defect ratios
The OEE target is generally set for one year and is underpinned by a penalty clause for non-achievement. It is reviewed annually, the idea being that the bar for OEE should be set higher each year as efficiencies improve. What makes this possible is the mapping of machine stock and the ongoing training of machine operators to perform daily, weekly and monthly tasks, such as checking the parameters for oil and slurry levels; machine alignment; greasing of key components; checking of cables; and reporting of any items out of the ordinary in the machine operation.
The dynamic nature of outsourcing means that effective reporting to the client is essential. On larger projects, this is achieved via an onsite project manager with a suite of analysis and reporting software. Employing this resource, weekly reports regarding production performance and costs are produced, and also monthly reports regarding performance against OEE and production trends.
Complementing the reports procedure, a review is held quarterly, to assess progress in target areas. The review asks questions such as: “should we increase our OEE targets in the light of performance improvements”? And,“how are we performing financially for the next quarter”?
Details available from: Deritend Group Ltd, Tel: +44 (0) 1902 426354, Fax:+44 (0) 1902 711926, E-mail: wolverhampton@deritend.co.uk
