HYDRAULICS When a hydraulic hose assembly is removed because of a problem at one end, there can be a strong temptation to salvage what appears to be perfectly serviceable hose. Cut away the affected section, fit a new coupling and the assembly can potentially be returned to service quickly and at considerably lower cost. It is an understandable proposition, particularly when downtime is involved, but it is not an acceptable approach under BFPA practice. That position is consistent with BS EN ISO 4413:2010, Hydraulic fluid power – General rules and safety requirements for systems and their components. Clause 5.4.6.5.1(a) requires hose assemblies to be constructed from hose that has not previously been used in operation as part of another hose assembly and which fulfils the relevant performance and marking requirements. The significance of the word ‘shall’ in the standard is important: compliance with that requirement is necessary to claim compliance with the standard. BFPA’s own position is equally clear. Its Position Paper PP1 states that hoses shall not be re-ended, while no re-ending of hose assemblies is a mandatory requirement of the BFPA Approved Hose Assemblies Scheme. D8 applies this requirement to participating fixed hose assembly facilities, with corresponding requirements applying to mobile workshops under D12. The reasoning is not simply procedural. Once a hose has been put into service, its previous condition and loading can no longer be treated as known. BFPA identifies the possibility that hose may have been stretched, crushed, degraded by sunlight or damaged by chemicals. Its D8 guidance also refers to the effects of heat, flexing, pressure pulsation, sunlight and ozone during service. These factors matter because a hydraulic hose is not simply a rubber tube onto which a fitting is attached. Its performance depends upon the relationship between its constituent materials and reinforcement, as well as the correctly specified coupling system and assembly process. BFPA notes that service-related degradation can cause the rubber to harden. If used hose is subsequently re-swaged, the reinforcement may lose its bond with the rubber and hardened rubber may not flow over the insert as required. D8’s conclusion is that a correct swage cannot therefore be assured. An apparently sound external surface does not resolve that uncertainty. Cutting a hose back beyond visible damage may remove the obvious defect, but it provides no reliable means of establishing what mechanical or environmental conditions the remaining hose has experienced. Re-ending should also be distinguished from mixing and matching components. They are separate issues within BFPA’s requirements. The Approved Hose Assemblies Scheme prohibits re-ending and also prohibits unapproved combinations of hose, fitting and ferrule. A new assembly should use compatible components assembled in accordance with the original hose and coupling supplier’s requirements. Selecting the Why re-ending a hydraulic hose is never worth the risk correct fitting does not make it acceptable to install that fitting on previously used hose. When an assembly has failed, replacement also provides an opportunity to consider why. Hose routing, bend radius, movement, abrasion, temperature, pressure and external loading may all warrant examination depending on the circumstances. Where the cause is not obvious, simply concentrating on the visibly damaged end risks overlooking the conditions responsible for the failure. For the hose assembler, the practical answer is therefore uncomplicated. Do not attempt to recover a used hose by fitting a new end. Where necessary, investigate the reason for the original failure, then manufacture the replacement from new hose using the correct compatible components and the relevant manufacturer’s assembly instructions. That may require more material than cutting back the old hose, but it restores something that re-ending cannot: a hose of known, unused condition at the beginning of the assembly process. 18 HYDRAULICS & PNEUMATICS September 2026 www.hpmag.co.uk BFPA guidance is clear that used a hydraulic hose should not be re-ended. The reasoning reflects the requirements of BS EN ISO 4413:2010 and the uncertainty surrounding the condition and service history of a used hose. H&P reports. Used hydraulic hoses should not be re-ended
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