Anyone who builds, repairs or refurbishes machine tools will know that ballscrew lead times are getting longer and longer. Most people are visibly shocked when they hear that a new ground ballscrew which before Christmas took around 6-8 weeks to manufacture is now taking 18-20 weeks – and that’s just for standard stock. Anything unusual or bespoke is taking even longer – delivery dates are now deep in to 2019.
Lead times for lower precision rolled ballscrews have suffered in a similar way although the lengthy lead times have lagged a little behind ground ballscrews. Rolled ballscrews are easier to manufacture and therefore cheaper and stockists are more likely to have some left on the shelves so its only when these stocks dry up that the lead time issues begin to surface. It’s generally only the machine tool OEMs who keep their own bespoke ground ballscrews in stock still have ballscrews on the shelf however even these OEMs are quoting longer and longer lead times for replacements.
For machine and machine tool builders its causing huge anxiety as they find it difficult to meet their order deadlines. They suffer the double whammy of trying to source available linear guides as well which are also suffering from longer and longer lead times. With all the major brands quoting impossible lead times – and in some cases refusing to quote at all – buyers and engineers are turning to smaller niche players in the market and looking further afield to try to source ballscrews and linear guides within acceptable lead times.
So, what’s happened to cause the disruption? Well, the answer is never simple. It seems to be the result of a number of converging pressures across the World which all impacted around the turn of the year.
Firstly, there are pressures on the availability of steel which is the main raw material for ballscrews and linear guides. The demand for steel, generally seen as a barometer of global economic health, is forecast to grow by 4.5% this year and by around 4.9% next year in emerging and developing countries. Even in developed markets the growth rate is around 1.8% so there is a huge squeeze on the supply of raw material.
Secondly, there has been a sustained upswing in global growth from China, the Eurozone and across to the US. This has put pressure on the major ballscrew and linear guide manufacturers. Their normal production capacity became full very quickly and they have struggled to increase capacity to meet the new demand. Ballscrews and linear guides have become more difficult to source within acceptable lead times which means that almost any spare stock is gobbled up as manufacturers stock up on their critical spares.
Lastly, for us in the UK there is also a Brexit effect. The fall in the value of the Pound and a more buoyant global demand for goods has shifted the economy towards stronger export growth rather than domestic growth. Anecdotally, we have also seen examples amongst UK suppliers that their European manufacturers are preparing for a no-deal Brexit by stockpiling critical, hard to source, niche or unique items which are likely to impact on production if no trade deal with the EU is achieved.
At the moment there’s a big melting pot of pressures bubbling away whilst we wait for capacity to increase so that we can get back to normality – but we can’t see the situation changing anytime soon. Ballscrews are a complex business and the barriers to entry are quite high. It’s difficult and costly to increase capacity and given that it’s taken nearly 10 years for the world economy to finally recover from the ravages of the 2008 financial crisis one can understand why investors are reluctant to invest in additional capacity.
So, what should be your coping strategy? We have 3 ways you can cope with the delays that longer lead times can cause:
Repair – If you are a manufacturer looking to repair, maintain or refurbish existing machinery then a ballscrew or linear guide repair is always a good option. Turnaround times are quick, often as fast as 24-48 hours and the end result is normally a ballscrew that performs to an ‘as new’ standard.
Maintain – its now more important than ever to nurture your ballscrew and linear guides and value them for the scarce commodity they are. Oil or grease them well and service them regularly with a ballscrew refurbishment specialist. Its better to lose one or two days production than to have to wait 6 months for a replacement.
Stock up – If you have critical machinery then you need to buy a spare. Ordering a spare ballscrew or linear guide now means that you will not have to wait so long when you really need it.
Unfortunately, for machine and machine tool builders there is very little that can be done but you do need to source your ballscrew and linear guide requirements as soon as you can – a good 6 months before you need them and start to look further afield to ballscrew specialists rather than go through the usual distributors. Ultimately though you need to plan well ahead than you are used to doing to make sure you have your ballscrews and linear guides when you need them.
PGM Reball Ltd are ballscrew experts specialising in repair, sales and manufacture of ballscrews. With an international reputation in their field PGM Reball can source hard to find ballscrews and linear guides using their extensive network of contacts across the globe. This article was first published in the September 2018 Issue of the MTDCNC Magazine