September 2019

HYDRAULICS Keeping safe with accumulators Within the fluid power world, accumulators play a vital role in supplying a stored source of hydraulic fluid under pressure as and when required. However, the simple fact is failure or improper selection or improper use of accumulators and their related accessories can cause death, personal injury and property damage. Therefore, before selecting or using any accumulator or related accessories, it is important that users read, understand and follow the instructions provided by the supplier. Understandably, the provider is unlikely to accept any responsibility for any incidental, consequential or special damages that arise from the use of the accumulator, accessories or accompanying software. User responsibility Due to the wide variety of accumulator applications and operating conditions which exist, Parker does not warrant that any particular accumulator is suitable for any specific application. With this important safety theme in mind, Parker has produced a safety guide – Safety Guidelines For Accumulator Division Products – for general information only (it does not analyse all of the technical parameters that must be considered in selecting a product). In the case of Parker, the hydraulic and pneumatic accumulators and accompanying software have been developed in accordance with Parker’s design guidelines and comply with all appropriate EC Directives. These accumulators do not necessarily meet the requirements of other standards or agencies. The user, through his or her own analysis, is solely responsible for: Making the Final Selection of the accumulators and related accessories based on all of the conditions and requirements of the application. Assuring that the user’s requirements are met and that the use presents no health or safety hazards. Assuring that the accumulators meet specific design requirements of the agency(s) regulating the design of the user’s equipment. Determining that the final design complies with the appropriate EC directives. Testing the entire application system. Providing all appropriate health and safety warnings on the equipment on which the accumulators are used. Providing proper short term and long- term maintenance for the application based on its operating conditions. Seals Part of the process of selecting an accumulator is the selection of seal compounds. Be sure to read the Choose Seals and Seal Advisor information in the 22 HYDRAULICS & PNEUMATICS September 2019 www.hpmag.co.uk Choose Modifications section of this programme before completing your selection. The working environment of an accumulator may allow fluids such as cutting fluids, wash down fluids etc. to come into contact with the external surfaces of the accumulator. These fluids may attack the accumulator ‘O’ ring seals and must be taken into account when selecting and specifying seal compounds. Dynamic seals will wear. The rate of wear will depend on many operating factors. Wear can be rapid if the accumulator is not mounted vertically or if the accumulator has been improperly serviced. The user must take seal wear into account in the application of accumulators. The hydraulic fluid must be filtered to ISO 4406 class 19/15 or better, otherwise premature seal leakage and failure may occur. Leaking hydraulic fluid is a hazard and may be a fire risk and care must be taken to contain it safely and keep it well away from any heat or ignition sources. Safety first So, before sourcing and operating an accumulator, think safety first and follow the supplier’s guidance to the letter. This will then stand you in the best stead for deriving the very best rewards from your accumulator. www.parker.com Andreas Lengnowski: “Before sourcing and operating an accumulator, think safety first and follow the supplier’s guidance to the letter.” Andreas Lengnowski, market manager, Parker Hannifin Manufacturing Germany GmbH & Co. KG, Cylinder, Accumulator & Cooler Division Europe, provides safety guidance for selecting and using hydro-pneumatic accumulators and accessories.