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aerospace climate control electromechanical filtration fluid & gas handling hydraulics pneumatics process control sealing & shielding Hydraulic Hose, Fittings and Equipment Technical Handbook Technology Today’s hose and fitting technology must meet the constantly increasing challenges and requirements of modern machines and equipment in demanding applications and arduous environments. To satisfy these needs, Parker is continuously developing new state-of-the-art products and technologies. Parkrimp No-Skive Technology – the safe connection Hose fittings have an impact on the overall efficiency and safety of a hydraulic system. The No-Skive concept was launched by Parker Hannifin some 30 years ago but continual development and the use of modern materials and production techniques have resulted in a state-of-the-art hose to fitting connector. No-Skive versus Traditional Skive Fittings Skive • Assembly of No-Skive hose and Cr(VI)-free fittings does not require removal of the outer cover of the hose: • Premature hose failure caused by under or over skiving is avoided. • The steel wire reinforcement is protected against corrosion. • The steel wire reinforcement is mechanically protected during hose fitting assembly by the outer rubber cover. • No-Skive No-Skive Cr(VI)-free fittings are designed so that the teeth of the shell bite down to the wire to give a metal-to-metal grip. Parker Hose Products Division defines the power-grip connection between the crimp fitting and the hydraulic hose as the critical zone in all flexible hose connections. Correct combination of Parker No-Skive hose and fittings guarantees a total form lock connection between shell and reinforcement and assures a safe and leak free long service life. Environmentally Friendly Plating Process Since 1st July 2007 the EU End-of-life Vehicle Directive (ELV) came into force. European Community Directive 2000/53/EG of 1st July 2002 • Directive manages vehicle recycling • Prohibition on the use of chromium-6, mercury and lead with specified exceptions and the prohibition of cadmium • Metallic chromium and chromium-3 compounds may still be used Chromium-6 has been classified in the EU Directive 67/548/ EWG as Category 2, which means that this material can under certain circumstances act as a carcinogenic. Skin contact can bring about allergix reactions. Since 2006, all Parker steel fittings have been manufactured using trivalent chromate (Chromium-6-Free) plating . This new process enhances the corrosion resistance of the fittings, and is more environmentally friendly than the previous hexavalent chromate plating. While the fitting function will not change, the fitting color will. Fittings plated with trivalent chromate will be silver in color, not gold. The new plating process is implemented worldwide at all Parker facilities. Custom Fittings for Short-Run or Special Applications Non-standard and customised hose fittings are available from the Rapid Service Unit The Rapid Service Unit (RSU) can provide: • Jump sizes • Specific end-configurations • Specific drop lengths • Fitting/tube combinations • Customised prototypes • Any batch size upwards from a single piece Material options include steel, stainless steel, brass and special materials on request. Going Green: The implications for hoses Protecting the environment and controlling pollution are gaining momentum in response to priorities being set by governments and local authorities; it is becoming an important factor in the production of many products. Whether in municipal vehicles, construction equipment, agricultural machinery or forestry vehicles, the trend towards using biodegradable oil in hydraulic systems is increasing. Hose Products Division Europe offers a full range of hoses with pure nitrile inner tubes, from 1 and 2 wire braided through to 6-layer multi-spiral hoses. These hoses offer exceptional hydraulic oil and biodegradable oil compatibility up to 100 °C together with the advantage of no loss in pressure capability. Hybrid Push-Lok Technology – the excellent combination of two basic materials Through interactive development of both materials and manufacturing processes, the combination of polyurethane and synthetic elastomer has successfully resulted in the creation of a hybrid Push-Lok hose, with exceptional technical properties. • Hose cover made of high-quality polyurethane, featuring high resistance to welding spatter and abrasion. • The high tensile textile braid reinforcement ensures a firm grip of the hose onto the fitting and prevents it from pulling off. • Synthetic elastomer core tube resistant to hydraulic fluids, dry air, water, water emulsions, etc. Technical Handbook Index Index Hose and Fittings Terminology – The basics. . . . . . . . . . . Aa-1– Aa-4 Safety Pre-Caution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-5 Safe Hose Assemblies in 8 Steps. . . . . . . . . . . . . . . . . . . . . . . . Aa-6 1 Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-6 2 Size. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-6 3 Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-7 4 Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-7 5 Fluid Compatibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-8 6 Hose Fittings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aa-8 7 Hose Assembly Manufacture. . . . . . . . . . . . . . . . . . Aa-9 – Aa-10 8 Routing / Installation / Environmental influences. . Aa-11– Aa-13 How to Order (Part number description). . . . . . . . . . . . Aa-14– Aa-15 Technical Data Hose Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ab-2 Hose Fittings Pressure Ratings. . . . . . . . . . . . . . . . . . . Ab-3 Hose Fittings Overview . . . . . . . . . . . . . . . . . . . . Ab-4– Ab-5 Hose Fitting Nomenclature. . . . . . . . . . . . . . . . . . Ab-6– Ab-9 Classification Body Type Approvals. . . . . . . . . Ab-10 – Ab-11 Conversion Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ab-12 Temperature / Pressure Chart. . . . . . . . . . . . . . . . . . . Ab-13 Flow Capacity Nomogram . . . . . . . . . . . . . . . . . . . . . . Ab-14 The Correct Method to Fit Female Swivel Ends. . . . . . Ab-15 Chemical Resistance Table . . . . . . . . . . . . . . . Ab-16– Ab-21 Safety Guide . . . . . . . . . . . . . . . . . . . . . . . . . . Ab-22– Ab-25 Identifying Fitting Types. . . . . . . . . . . . . . . . . . Ab-26– Ab-35 A-I Catalogue 4400/UK Notes Catalogue 4400/UK Technical Handbook Hose and Fittings Terminology – The basics Hose and Fittings Terminology – The basics ! Selecting the right hose and fittings combination usually belongs to the last steps in the design of a hydraulic system and its importance is often overlooked and underestimated. The right hose and fitting combination is however, vital for the overall functionality and long term service life of the complete system. This technical handbook and catalogue will provide a guide to correct hose and fitting selection, as well as highlighting the important safety aspects to their usage as hose assemblies in the field. Cover Insulation/ Separation layer Steel wire braided reinforcement Inside tube Hose Typically a rubber hose is constructed of an extruded inside synthetic rubber tube that has the sole purpose to keep the conveyed fluid in the hose. The elastomeric nature of rubber requires that a reinforcement layer be wound or braided around the tube in order to hold the internal pressure. The reinforcement layer(s) are either textile or steel (or both). To protect these inner layers of the hose from the ambient conditions, an outer synthetic rubber cover is extruded around the reinforcement. Hose Assemblies Hose Assemblies Installation The combination of a hose and hose fitting(s) to make a hose assembly, is a critical process that needs to be carried out by professionally trained personnel who follow strict assembly instructions. Improperly assembled hose fittings can separate from the hose and may cause serious injury or property damage from whipping hose, or from fire or explosion of vapor expelled from the hose. (See „Safe Hose Assemblies in 8 Steps“, Page Aa-8) The hose assembly must be operated within specific limits to maximise a safe and long term service life. These limits are defined in this catalogue and also by both governmental standards and institutional organisation’s and specifications such as the ISO 17165-2, SAE J1273 or EN982. Aa-1 Catalogue 4400/UK Technical Handbook Hose and Fittings Terminology – The basics Working Pressure Hose and fitting selection must be made so that the published maximum recommended working pressure of the Hose and fitting are equal to, or greater than the maximum system pressure. Surge pressures or peak transient pressures in the system must be below the maximum working pressure of the hose assembly. Surge pressures and peak pressures can usually only be determined by sensitive electrical instrumentation that measures and indicates pressures at mili-second intervals. Mechanical pressure gauges indicate only average pressures and cannot be used to determine surge pressures or peak transient pressures. Proof Pressure Test This test is typically carried out on customer request according to a method defined by the ISO 1402 standard. The test should be made at normal ambient temperature with a proof test bench using water or another suitable liquid. The hose assembly should be pressurised for between 30 to 60 seconds at twice the working pressure of the hose assembly. There should be no leakage or pressure drop. A complete test report should be provided together with the hose assembly to the customer. Burst Pressure All hoses in this catalogue have a pressure design factor of 4:1, implying therefore that the burst pressure (hose destruction) is minimum 4 times the published working pressure. Published burst pressure ratings for hose are for manufacturing test purposes only – burst pressure should never play a role in the selection of a hose. x x x Fluid Compatibility The hose assembly (hose inner tube, hose outer cover and hose fittings) must be chemically compatible to both the fluid being conveyed by the hose as well as the medium surrounding it. (the chemical resistance table contained in the catalogue, indicates only the resistance of the hose innertube to the respective fluid) Temperature Range Temperature range In order not to negatively effect the properties of the rubber hoses it should be made certain that fluid and ambient temperatures, both steady and transient, do not exceed the limitations of the hose as published in the catalogue. Temperatures below and above the recommended limit will degrade the hose and failure may occur and release fluid. The mechanical properties of the hose are also influenced by low or high temperatures and should be considered when designing the system. Aa-2   -50   +100 Catalogue 4400/UK Technical Handbook Hose and Fittings Terminology – The basics Hose Size The power transmitted by means of a pressurised fluid varies with pressure and rate of flow. The size of the components must be adequate to keep pressure drops to a minimum and avoid aging due to heat generation or excessive fluid velocity. Parker uses the internationally recognised hose dash size as a measurement of the size of their hoses. This size is a measurement of the inside tube of the hose – not the wall outer diameter. Size -6 ⇒ ⇓ I.D. -6 Inch 6/16 mm ⇒ 6/16 * 25,4 = 9,525 ⇓ 3/8 DN ⇒ 10 9,5 10 ⇓ ⇓ Hose Bending Radius The minimum bend radius of a hose refers to the minimum radius that the hose may be bent through whilst operating at the maximum allowable published working pressure. Bending radius is not a measurement or indicator of hose flexibility. The catalogue specified values of bending radii are based on international or Parker specifications and have been proven through rigorous impulse testing of the hose assemblies. Bending the hose below the minimum bending radius leads to loss of mechanical strength and hence possible hose failure. A minimum straight length of 1,5 times the hose’s outside diameter (D) shall be allowed between the hose fitting and the point at which the bend starts. INCORRECT Hose r Bending Radius D CORRECT Hose Assembly Routing The routing of a hose assembly in such a manner so as to avoid any damage to the hose by stretching, compression, kinking or abrasion over sharp edges is essential, to assure maximum service life and safety. Aa-3 Catalogue 4400/UK Technical Handbook Hose and Fittings Terminology – The basics Hose and Fittings Storage A system of age control should be maintained to ensure that hose is used before its shelf life has expired. Shelf life is the period of time when it is reasonable to expect the hose to retain full capabilities for rendering the intended service. Hose shall be stored in a manner that facilitates age control and first-in, first-out (FIFO) usage based on the manufacturing date on the hose or hose assembly. The shelf life period of rubber hose in bulk form or hose made from two or more materials (hose assembly) is difficult to define as so many factors can detrimentally influence the hoses suitability for use. In the German speaking countries the “rules” that must be followed are stated in the DIN 20066:2002-10 and referred to by the general organisation of trade associations (Berufsgenossenschaft) in their actual publication ZH1/74 from April 2005 – safety regulations for hydraulic hose assembies. Excerpt DIN 20066:2002-10: For the production of hose assemblies the hose (bulk hose) must be younger than 4 years according to the hoses date of manufacture. The service life of a hose assembly, including any period of storage should not exceed 6 years; the period of storage should not exceed 2 of these 6 years. Additionally, the International Standard Organisation (ISO) has prepared a draft version of a guideline for hose/hose assembly usage that differs slightly from the German guideline. The ISO/TR 17165-2 states that the shelf life of hose as bulk hose or as hose made of 2 or more materials should not exceed 40 quarters (10 years) from the date of manufacture of the hose if stored in accordance with ISO 2230. After all cases of hose storage, if visual inspection gives rise to any doubts as to the functionality of the hose (cracks in the cover, rust etc), pressure testing should be carried out before use or the hose should be disposed of. Hose assemblies should always be considered as safety relevant components, so no risks should be taken. Hose storage – Best practices: – Store in a clean, cool and dry area (≈ room temperature) – Avoid direct sun light or moisture – Do not store near high power electrical equipment – Avoid contact with corrosive chemicals – Avoid Ultraviolet light – Insects/Rodents – Radioactive materials Fittings storage – Best practices: – Additionally to the factors above the following points should be observed for storage of hose fittings – Store fittings in clearly marked closed containers such as the original Parker packaging. – A stock rotation system (FIFO) should be in place so that a shelf life of 2 years is not exceeded for fittings with O-rings as they may degrade as a result of normal environmental conditions, leading to possible system leakages or contamination. Aa-4 10 Years Catalogue 4400/UK