• Montage
  • Montage
  • Montage
  • Montage
  • Montage
  • Montage
  • Montage
  • Montage
  • Montage
  • Montage B
  • Montage
  • Montage
  • Montage
Dec10

Why You Should Never Re-End a Hose Assembly

As proud members of the BFPDA, we place safety first. That is why Pegasus Hydraulics Ltd never condones the re-ending of hose assemblies – this is a dangerous practice with potentially fatal consequences.

BFPA POSITION PAPER (PP1) – HOSE RE-ENDING

Manufacturing companies do not condone the re-ending of their flexible hose products.

There is a high probability that re-ending will result in a situation when an injury occurs and the Company’s insurance will not accept liability due to global standards that clearly advise NOT to do so.

It is impossible to know whether an original hose has been stretched, crushed, degraded by sunlight or damaged by chemicals, the hose assembly safety, therefore, cannot be guaranteed if a new end is fitted on a used hose.

The British Fluid Power Association (BFPA) position is that hose(s) shall not be re-ended.

Fluid Power

The following standards that most fluid power ‘machinery’ manufacturers use, in order to achieve a ‘presumption of conformity’ with the Machinery Directive 2006/42/EC, are nothing if not clear on the subject:

BS EN ISO 4413: • Clause 5.4.6.5.1 a) states: “hose assemblies shall be constructed from hoses that have NOT been previously used in operation as part of another hose assembly and that fulfil all performance and marking requirements given in appropriate standards”

BS EN ISO 4414: • Clause 5.4.5.9.1 a) states: “hose assemblies shall be constructed from hoses that have NOT been previously used in operation as part of another hose assembly

In CEN and ISO parlance, the word shall is interpreted to mean ‘must comply’, and is non- negotiable. If the ‘shall’ requirements of such a standard are not met compliance with the standard concerned is not possible.

Both BS EN ISO 4413:2010 and BS EN ISO 4414:2010 are ‘transposed, harmonised standards’ which means that the members of the European Union (EU) have adopted the standards and have withdrawn any conflicting national standards. If you are supplying fluid power ‘machinery’ in the EU, it is very likely indeed that you will have to comply with the requirements of these standards.

If the product is for export outside of the EU, the customer may require compliance with BS EN ISO 4413 and/or BS EN ISO 4414.

As well as effectively banned in Europe, the practice of re-ending hose also destroys all the hard work that goes into an effective quality assurance programme.

Water Jetting

The Water Jetting Association’s Code of Practice was amended to comply with

BS EN 1829-2:2008 – a European standard that applies to hoses, hose lines and connectors intended to be used with high-pressure water jet machines operating at 350 bar and above

It therefore covers most water jetting applications and some drain cleaning applications:

• Clause 5.1 states: “Hoses, hose lines and connectors have to feature a certain structure in order to guarantee safe operation when used properly. They must not bear any risks for the operator or for the workplace and its environment. The design of any connector safety devices has to provide safe operational performance to eliminate any risk or hazard for the operator or their environment. However, improper use of a hose line or the connectors may result in hazardous situations and shall be avoided.

NOTE: Correct assembly of hose lines requires specific knowledge and skills, also specific equipment.

Health and Safety Executive (HSE)

The HSE Guidance Note GS 4 (fourth edition) entitled ‘Safety requirements for pressure testing’ is aimed at employers, supervisors and managers responsible for pressure testing and addresses safe systems of work, safeguarding and maintenance.

Feb06

Stainless steel life cycle costing

When specifying the material grade of any installation, whole life-cycle costing reveals the cost-effective winner.

Life cycle costing (LCC) Stainless steel is sometimes considered to be an expensive material. However, experience has shown that using a corrosion resistant material in order to avoid future maintenance, downtime and replacement costs can produce economic benefits which far outweigh higher initial material costs. Life cycle costing (LCC) quantifies all the costs - initial and ongoing - associated with a project or installation. It uses the standard accountancy principle of discounted cash flow to reduce all those costs to present day values. This allows a realistic comparison to be made of the options available and the potential long term benefits of using stainless steel to be assessed against other material selections. The present day value represent the amount of money which would have to be invested today in order to meet all the future operating costs - including running costs, maintenance, replacement and production lost through downtime. These are added to the initial costs to give the total LCC:
where AC = initial materials acquisition costs IC = initial fabrication and installation costs N = desired service life of project in years i = discount rate (calculated from interest and inflation rates) OC = operating and maintenance costs in year n LP = lost production and downtime costs in year n RC = replacement costs in year n Once the cost data have been gathered, the calculation of the life cycle cost is straightforward. Software packages are available which prompt the user to collect the relevant data, carry out the calculation and allow different options to be compared easily. Example (see reference "Applications for stainless steel in the water industry") Galvanised carbon steel and Type 316 stainless steel were both candidate materials for ductwork to remove odorous fumes in a sewage inlet works. The galvanised steel required a multi-stage site-applied painted coating whereas the stainless steel could be installed in a single operation. The galvanised steel was expected to need maintenance every 5 years, and replacement after 15 years. The stainless steel equipment was designed for a 30 year service life, with maintenance every 10 years. A 10% interest rate and 5% inflation rate were assumed, giving a discount rate of 4.76%.
Not only was the stainless steel option only slightly more expensive initially (because of the lower installation cost) but it showed a distinct life cycle cost advantage following the anticipated replacement of the galvanised steel plant after 15 years (see graph). The stainless steel option was chosen (see picture).
Further information on Life Cycle Costing can be found on the ISSF Website.
[12 3 4 5  >>  

Lloyds Register Logo

Lloyds Register Logo

Germanischer Lloyd Logo

RINA logo