A hydraulic hose bursts on a press, and the maintenance team needs a replacement by the next shift. The old hose has a part number printed along its length, a crimped fitting at each end, and a thread nobody has measured. The local supplier has a hose of the same size. It fits, it holds for a month, and then the fitting blows off — because the hose and the fitting came from different makers and were crimped to neither maker’s instructions.
Hoses and couplings look like the simplest items on a spare-parts list. They are not, because a hose assembly is a system: hose, fitting, crimp and connection must all match each other and the fluid. This article sets out how to specify each type — hydraulic, pneumatic, transfer and food — by the standards and data that a supplier anywhere in Asia can quote against, and what to check before an assembly goes on a machine.
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A hose order has six lines, not one
Specify the hose by its standard and type, its size, its working pressure, the fluid and temperature, the end fittings, and the length measured the way the supplier measures it.
| Line | What it fixes | Example |
|---|---|---|
| Hose standard and type | Construction and performance class | ISO 18752 class and type; EN 853 type; maker’s part number |
| Nominal size | Inside diameter | Nominal size as the standard defines it |
| Working pressure | Maximum pressure in service | From the standard’s class, or the maker’s datasheet |
| Fluid and temperature | Compatibility of the tube and cover | Mineral hydraulic oil; water-glycol; compressed air; food liquid |
| End fittings | Thread or connection form at each end and orientation | Thread standard and size; flange type; quick coupling series |
| Length | How the assembly fits | Overall length including fittings, and how it is measured |
Write the fluid every time. A hose rated for mineral oil may not be suitable for a water-based or synthetic fluid, and the standard leaves that decision to the user and the hose maker.
Hydraulic hoses: ISO 18752, ISO 1436, EN 853 and JIS K 6349
Hydraulic hoses are specified either by a performance standard such as ISO 18752 or by a construction standard for wire-braid or spiral-wire hose, and the end fittings are specified separately.
ISO 18752:2025 (Rubber hoses and hose assemblies — Wire- or textile-reinforced single-pressure types for hydraulic applications — Specification) is the current edition, published in June 2025. ISO describes it as covering hoses and hose assemblies in ten classes, four grades and seven types, nominal sizes 5 to 102, with each class having a single maximum working pressure across all sizes. It applies to oil-based hydraulic fluids classified in ISO 6743-4. It sets no requirements for connection ends, and ISO notes that compatibility of the hose with the fluid is the responsibility of the user together with the hose maker.
The construction-based standards are still in daily use on spare-parts lists:
| Standard | Covers | Note |
|---|---|---|
| ISO 1436 | Wire-braid-reinforced hydraulic hoses for oil-based or water-based fluids | ISO’s browsing platform shows a 2026 edition; confirm the edition with the supplier |
| ISO 3862 | Rubber-covered spiral-wire-reinforced hydraulic hoses | 2020 edition is current; ISO lists it for revision |
| EN 853 / EN 856 / EN 857 | Wire-braid, spiral-wire and compact wire-braid hydraulic hoses (CEN) | National catalogues show different editions; confirm the one ordered |
| JIS K 6349 | Steel-wire or textile-reinforced rubber hoses for hydraulic use | The JIS designation you may meet on Japanese drawings and spare-parts lists |
Replacement orders are often placed by maker’s part number — for example hoses from Parker or Gates printed with the maker’s code. That is a valid specification if the part number is read in full, but it is a brand specification. If you accept an alternative, ask the supplier to show which standard and class both hoses meet, and replace the fittings too.
Do not mix hose and fittings across makers without approval. Crimp fittings are designed for a particular hose construction, and the crimp diameter comes from the maker’s instructions. Ask the assembler which hose maker’s fittings and crimp data it uses, and require it to state both on the assembly record.
Hydraulic end connections and quick couplings
Identify every end connection by its standard and size before ordering; threads and flange connections that look alike are often not interchangeable.
End fittings on hydraulic assemblies follow thread and flange standards that differ by region and by machine maker — metric, BSP, NPT, JIS and SAE forms all appear on equipment in Asia. Measure the thread, check the sealing method (cone, O-ring, flat face, thread sealant) and record it. For taper pipe threads, ISO 7-1 and JIS B 0203 describe threads where the pressure-tight joint is made on the thread, and ASME B1.20.1 describes NPT; they are not the same thread. See JIS, ASME and EN piping standards compared.
For hydraulic quick-action couplings, ISO 7241:2023 (Hydraulic fluid power — Dimensions and requirements of quick-action couplings) specifies interface dimensions and basic performance for two series. ISO describes Series A as used predominantly in Europe and preferred worldwide for agricultural and forestry machinery, and Series B as used predominantly in North America and in the chemical industry. The two series do not connect to each other. ISO 16028:2023 covers flush-face hydraulic couplings. Write the standard and series on the order, not only “quick coupling”.
💬 We source hoses, fittings and couplings from manufacturers and stockists across Asia, by standard or by maker’s part number. See pipe fittings, valves and couplings.
Pneumatic hoses and couplings
Compressed-air couplings must match the profile already installed in the plant; a coupling of the same nominal size from another profile will not connect.
ISO 6150:2018 (Pneumatic fluid power — Cylindrical quick-action couplings for maximum working pressures of 1 MPa, 1,6 MPa and 2,5 MPa) covers plug connecting dimensions, specifications, application guidelines and testing. Plants also use profiles that are not ISO 6150, and couplings are often specified by maker and series — Nitto Kohki’s Cupla range is one example. Before ordering, take the plug already installed on the machine, record its maker and series, and order the socket or plug to match.
For the hose itself, state the material (rubber, PVC, polyurethane, polyamide), the inside and outside diameter (push-in fittings depend on the outside diameter), working pressure and temperature, and whether the hose must be antistatic or suitable for welding spatter or oil mist.
Transfer hoses and camlock couplings
For liquid and bulk transfer, specify the hose by fluid, pressure and vacuum, and the camlock couplings by EN 14420-7 type, size and material.
EN 14420-7:2022 (Hose fittings with clamp units — Part 7: Cam locking couplings) covers the design, materials, dimensions and marking of cam-locking couplings for transferring liquids, solids and gases, but not liquefied gas or steam. Its scope gives a working range of 0,8 bar to 16 bar for most couplings and −0,8 bar to 10 bar for aluminium-cast couplings and all DN 100 couplings, in a working temperature range from −20 °C to +65 °C. A corrigendum was published in 2023. Camlocks made to other dimensional systems also circulate; confirm that new couplings mate with the ones on your tanks and trucks before buying a full set.
| Hose type | Key specification lines | What to check on delivery |
|---|---|---|
| Hydraulic | Standard and class/type, size, working pressure, fluid, end fittings, crimp data | Hose layline, fitting marking, assembly record |
| Pneumatic | Material, ID and OD, pressure, coupling maker and series | Plug fits the existing socket |
| Chemical transfer | Fluid and concentration, temperature, pressure and vacuum, electrical continuity | Compatibility statement from the hose maker |
| Camlock couplings | EN 14420-7 type and size, material, gasket material | Mates with existing couplings |
| Food | Food-contact compliance basis, cleaning method, temperature | Declaration of compliance for the destination |
| Steam | Steam-rated hose and fittings, safety clamps | Do not substitute general-purpose hose |
Food and beverage hoses
A food hose must comply with the food-contact rules of the country where it is used; ask the supplier for a declaration that names those rules, not just for “food grade”.
In the EU, Regulation (EC) No 1935/2004 sets the general principles of safety and inertness for all food contact materials, and Regulation (EC) No 2023/2006 sets good manufacturing practice. For plastics, Regulation (EU) No 10/2011 sets composition rules, a Union list of authorised substances and migration limits, and requires a declaration of compliance. The European Commission’s page does not list rubber among the materials with specific EU measures; where none exist, Member States may apply national rules. A rubber food hose for the EU therefore needs a declaration that names the national rules relied on.
For other markets, confirm the current rule in the country of use, and ask the hose maker for its declaration against that rule. “Food grade” printed on a hose is not a compliance statement.
Before an assembly goes on a machine
Check the layline, the fitting marking and the assembly record, and keep them together so the next replacement can be ordered exactly.
- The hose layline (the printing along the hose) shows the maker, type or standard, size and pressure. Photograph it.
- The fitting marking shows the maker and part number. Photograph both ends.
- The assembly record states hose and fitting part numbers, crimp data used, length, and any pressure test made on the assembly.
- Route and protect the hose as the machine maker requires; a correct hose installed with a tight bend or against an edge fails early.
Keep these records in your maintenance file. The next order then becomes a part-number order instead of a search. For plant spares consolidated across several suppliers, see consolidating Asian suppliers into one shipment, and for the Japanese-machinery side, genuine Japanese industrial parts.
💬 Building a spare-hose list for a whole line? Send us the machine list and photos and we will turn them into part-numbered specifications.
Frequently asked questions
1. Can I replace a branded hydraulic hose with another brand of the same size?
Only if the replacement meets the same standard and class for your pressure and fluid, and the fittings and crimp data come from the replacement hose’s maker. Replace the fittings with the hose.
2. Is ISO 18752 the same as EN 853 or ISO 1436?
No. ISO 18752 classifies hoses by performance and pressure class; ISO 1436 and EN 853 describe wire-braid constructions. A hose can be marked to more than one; check the layline.
3. Do quick couplings from different makers connect?
Only if they share the same profile. For hydraulics, ISO 7241 Series A and Series B do not interconnect; for air, match the profile already installed.
4. What makes a hose “food grade”?
Compliance with the food-contact rules of the country where it is used, shown by a declaration from the maker that names those rules.
5. What should a hose assembly record contain?
Hose and fitting part numbers, the crimp data used, overall length, end orientation, any pressure test made, and the assembler’s name and date.
Sources: ISO catalogue pages for ISO 18752:2025, ISO 1436, ISO 3862:2020, ISO 7241:2023, ISO 16028:2023, ISO 6150:2018 and ISO 7-1:1994; CEN standards EN 853, EN 856, EN 857 and EN 14420-7:2022 as listed by CEN national members; JISC database titles for JIS K 6349 and JIS B 0203; ASME B1.20.1 catalogue page; European Commission food contact materials legislation page (Regulation (EC) No 1935/2004, Regulation (EC) No 2023/2006, Regulation (EU) No 10/2011). Checked on 27 October 2026.