Cheap motors costing U.K. manufacturers millions
London, U.K. - British industry is wasting millions of pounds annually through the use of poor reliability motors from the Far East, says Steve Ruddell, senior VP of electrical machines at ABB.
By Control Engineering Staff
Steve Ruddell, senior VP of electrical machines at ABB.
London, U.K. - British industry is wasting millions of pounds annually through the use of poor reliability motors from the Far East, says Steve Ruddell, senior VP of electrical machines at ABB . The costs are measured in plant downtime, wasted energy, and replacement of the inferior motors.
Speaking at a press briefing in London, he said his concern was that the continued price erosion in motors that has benefited end-users and OEMs in recent years is about to backfire as a series of premature motor failures.
'In the last 12 months, ABB and its distributors have received many calls to replace motors from other manufacturers that have clearly failed through the use of inferior materials and low-cost production methods,' he said.
'We have seen motors running excessively hot; we have seen cracked castings, burnt-out windings, sub-standard insulation systems, and much more,' he added.
Showing thermal images of electric motors with sections running as hot as 140 degrees, he said it was 'more akin to an oven than a motor.' He provided samples of windings where intense heat had melted the protective varnish.
For applications that only need a motor to run a pump for two hours once a month in a non-critical application, it makes sense to sacrifice durability for price. But for continuous processes, where downtime is costly, users need to be more careful. The problem is, buyers can't see if there are second-rate materials inside.
As an example, he showed photographs of a Chinese-built motor 'Germana' made to German specifications which sells for
Motor manufacturing is a rather standardised operation, he said. No matter where it's done, about 55% of the cost is for materials, 15% for labour, and 30% for overhead. The only way to significantly reduce the cost is to make significant reductions in the materials, he said.
He said the purchase price of a motor is almost becoming insignificant when contrasted with operational costs.
'For every0 to 15 years of trouble free service.
'In many cases, engineers know a good motor when they see it, but are unable to put their finger on what it is that makes it good. As they are unable to quantify their requirements, their purchasing department simply buys them the cheapest motor that fits the specification.
'U.K. manufacturers are exposed to this because of fierce cost cutting,' he said. 'It is less of a problem in Germany, because buyers there are more life cycle conscious.'
Mr. Ruddell said ABB was establishing a web site www.abbmsp.co.uk where users can share their experiences with motors, both good and bad.
Control Engineering Daily News Desk
Michael Babb, editor, Control Engineering-Europe