July/August 2019

KNOWLEDGE BASE 22 HYDRAULICS & PNEUMATICS July/August 2019 www.hpmag.co.uk The white paper, entitled ‘Predictive maintenance – cheaper in the long run’, in the first instance highlights that the objective of any maintenance programme is ensuring that the point of catastrophic failure is never reached, while at the same time providing a cost-effective solution. To achieve these goals, the maintenance approach must indicate that action is taken as close to the end of useful component life as possible – before the point of rapid deterioration or breakdown. All of the commonly deployed maintenance strategies are assessed in the white paper for their strengths and weaknesses. Breakdown maintenance, for example, is extremely cost effective Predictive maintenance in hydraulic systems proves cheaper in the long run The operation of hydraulic systems is clearly critical, regardless of whether they function for 10 minutes every few weeks, or 24/7. Achieving an uptime utopia, however, depends largely on the successful implementation of an optimised maintenance strategy. In the hydraulics arena, many different maintenance strategies can be found, including those based on breakdown, preventative, predictive and proactive approaches. Today, there is a growing trend in support of a predictive maintenance approach, the explanation for which is outlined in a new white paper written by independent industry expert Steve Skinner in association with Webtec. provided no parts fail during the machine’s lifetime, or where the consequences of component failure are trivial. In terms of disadvantages, however, this type of approach essentially ‘gambles’ that a part will last for the working life of the machine. Moreover, in many industries, unexpected component failure will likely prove expensive, as well as dangerous. With regard to preventive maintenance, which involves estimating when machine parts are likely to wear out, then scheduling their replacement before this occurs, such a strategy is useful when component lifetimes can be predicted reasonably accurately and where operating life is relatively insensitive to operating conditions. Whenever useful lifetime is difficult to predict or significantly affected by operating conditions, then other maintenance procedures may be more appropriate. Foreseeing all possible eventualities Moving to proactive maintenance, this approach attempts to foresee all possible eventualities that could lead to a breakdown, then evaluate their likelihood of occurring and their effect on machine operation. Based on a combination of these parameters, potential failure causes or consequences can then either be eliminated or reduced to an acceptable Predictive maintenance aims to identify the ideal time for component replacement or overhaul.