How to Choose the Best Steam Hose & Fittings for Your Needs

Selecting the right steam hose and fittings is crucial to maintaining any high-temperature, high-pressure steam system. Whether you’re transferring steam for sterilisation, process heating or power generation, the hose and its terminations must match your system’s temperature, pressure, and chemical demands.

In this article, we’ll look at the different types of steam, before exploring the various hose materials and ISO classifications, so you can ensure your steam distribution system operates reliably, safely and with minimal downtime. Keep reading to learn more…

Understanding steam

Steam is classified according to its temperature, pressure, and moisture content. These factors dictate the energy content of the steam and its suitability for specific industrial applications. 

Broadly speaking, steam falls into three categories:

Dry steam 

Dry steam (saturated steam) exists at the highest temperature possible for a given pressure, with all water converted into vapour and no liquid droplets present. This form of steam carries maximum latent heat, making it extremely efficient for heat-transfer applications.

Common applications of dry steam include:

• Power generation in steam turbines, where consistent heat is crucial.

• Sterilisation of pharmaceutical and medical equipment, killing microbial bacteria without moisture damage.

• Heat exchange in process plants, where uniform temperature profiles are required.

• Food processing, particularly in blanching, cooking and pasteurisation, where condensation control is vital.

Wet steam

Wet steam contains bound liquid water droplets and exists at a lower temperature and pressure than its dry counterpart. The presence of moisture reduces its total heat content and can lead to inefficiencies or water hammer (a type of knocking noise in water pipes) if not managed correctly.

Typical uses for wet steam are:

• General heating systems, such as space and process heating, where precise temperature control is required but not critical.

• Humidification in textile and paper mills, where added moisture benefits the production process.

• Non-critical cleaning tasks that do not demand high steam quality.

Superheated steam

Superheated steam is generated by further heating dry steam beyond its saturation temperature at a given pressure. Lacking any moisture content, it will not condense until its temperature falls below the saturation point, making it exceptionally useful where condensation must be avoided.

Key applications of superheated steam include:

• High-efficiency steam turbines in power plants, where dry, high-energy steam maximises mechanical output.

• Industrial processes requiring sustained high temperatures without moisture, such as petrochemical cracking and certain metallurgical treatments.

• Situations involving rapid heat transfer without the risk of water droplet impingement, such as in specialised drying ovens.

Comparing the three steam types

* Moisture levels in wet steam vary depending on boiler design and operating conditions.

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How are steam pipes constructed?

In order to withstand the high temperatures, pressure fluctuations, and environmental hazards, steam hoses need to be resilient. They typically feature a three-part construction comprising a tube, one or more reinforcement layers, and an outer protective cover.

Tube

The tube is the innermost layer, and forms the core fluid-conveying path. This layer must resist steam, condensate and any additives. Most steam hoses use an EPDM rubber tube or a PTFE liner for chemical-resistant applications. 

Key properties of this layer include:

• Gas-tight, seamless construction that prevents vapour permeation and eliminates popcorning (the incident where the inner lining deteriorates due to the absorption and subsequent expansion of water vapour in the hose’s material).

• Homogeneous material free of joints or reinforcements, reducing internal stress points and burst risk.

• High resistance to heat ageing, abrasion from condensate flow and degradation from steam additives.

• Smooth bore for minimal pressure drop, easy cleaning and reduced scale or deposit build-up.

Reinforcement layer

One or two layers of braided or spiral steel wire provide the hose’s pressure-containing strength and structural integrity. This reinforcement also mitigates the risk of hose expansion under pressure and helps dissipate static electricity. 

Typical reinforcement features are:

• Braided stainless-steel wire, allowing smaller bend radii while maintaining pressure rating.

• Spiral-wound carbon or stainless steel for higher burst pressures and improved resistance to kink or collapse.

• Antistatic wire or textile elements that connect end fittings to create a continuous path for static dissipation.

• Corrosion-resistant coatings on metal wires to protect against steam-induced rust and hidden inlay corrosion.

Cover

The cover shields the internal layers from external threats such as abrasion, UV radiation, chemicals, and mechanical damage. Common cover materials include EPDM for general steam use and chlorobutyl for greater chemical and ozone resistance. 

Characteristics include:

• Resistance to weathering, ozone and sunlight, preventing cracking or embrittlement during outdoor service.

• Oil-resistant compounds that withstand incidental hydrocarbon spills without softening or tearing.

• Flame-retardant formulations that reduce fire spread and self-extinguish when exposed to open flame.

• Smooth or ribbed profiles to improve grip, reduce abrasion and facilitate visual inspection for wear.

When combined, the tube, reinforcement layer, and cover create a hose that meets precise steam-handling requirements.

Types of steam hoses

Steam hoses are engineered to withstand extreme heat, pressure and, in many cases, chemical exposure. The choice of hose material directly influences its operational lifespan, flexibility, safety, and suitability for specific applications. 

Before we get into the different types of steam hose, it is important to understand the classification that dictates the capabilities of a steam hose.

Steam systems must comply with all applicable safety regulations and industry specifications. In the UK and Europe, Pressure Equipment Directive (PED) 2014/68/EU governs steam components, while BS EN ISO 6134 provides a standardised framework for steam hose performance. It defines two primary classes:

These classifications help to make sure that the selected hose can handle both the pressure and temperature demands of saturated steam or hot water condensate.

For hygienic applications, FDA and European Hygienic Engineering & Design Group (EHEDG) standards apply. Always request certification documentation, such as CE marking, hydrostatic test reports and material traceability to verify regulatory compliance.

The most common constructions use synthetic rubber, PTFE (polytetrafluoroethylene) or stainless steel, each with advantages and limitations:

Rubber steam hoses

Rubber steam hoses typically use EPDM or a specialised synthetic compound. EPDM hoses stand out for the following reasons:

• High-temperature capability, often up to 150–160 °C for saturated steam.

• Excellent flexibility, even in cold environments, making installation and routing straightforward.

• Good resistance to heat, water, acids, alkalis, and ultraviolet light, making it suitable for environments with mechanical contact or movement.

• Cost-effective solution for standard steam applications, including food processing (when food-grade) and general heating.

However, EPDM hoses are not petrol-resistant. If exposure to oils or fuels is possible, a different cover material or hose type is recommended.

PTFE steam hoses

PTFE steam hoses are designed for extreme environments. Key characteristics include:

• Thermal resilience, tolerating temperatures from –60 °C up to 260 °C or higher for short bursts.

• Chemical resistance, impervious to most acids, solvents, and corrosive steam condensates.

• Low friction inner bore, promoting smooth flow and minimising pressure drop.

• Non-stick surface, reducing the risk of process fluid build-up and simplifying cleaning.

These hoses are ideal for steam applications in chemical processing, pharmaceutical manufacturing and any setting where both temperature and chemical compatibility are critical.

Metal steam hoses

Metal steam hoses are commonly constructed from stainless steel or specialised alloys. Their main advantages are:

• High-pressure tolerance, with some designs rated well above 20 bar.

• Exceptional durability in abrasive or mechanically demanding environments.

• Resistance to UV, ozone, oils, and a wide temperature range (often –50 °C to 600 °C).

• Long service life, even under continuous flexing or vibration.

These hoses excel in power generation, at petrochemical plants, and in any application requiring the ultimate combination of flexibility and robustness.

Cover types

The hose cover protects the internal layers from external hazards. Covers fall into two categories:

• Oil-resistant cover: these covers are designed to resist degradation when in contact with oils, greases, or fuel. They have a typical temperature range of up to 207 °C for saturated steam, 232 °C for superheated steam. These covers are common in chemical plants, refineries and any facility where incidental oil contact is likely.

• Non-oil-resistant cover: these are not designed for oil exposure, as they can swell, soften or crack if in contact with hydrocarbons. They generally offer a longer service life in clean, non-oily environments. They are suitable for general steam heating, humidification and food processing (with food-grade certification).

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What to consider when selecting a steam hose

Selecting the right steam hose is highly important, going beyond the realms of personal preference to find a conduit capable of meeting your strict requirements. When selecting hoses, the STAMPED mnemonic provides a good framework for evaluation:

Size

There are three components here to consider: length, diameter, and bend radius.

• Length: you need to make sure the hose length accommodates routing, thermal expansion and movement. Excessive length introduces pressure drop and kinking risk, while insufficient length can overstress fittings and cause premature failure.

• Diameter: you must match the inner diameter (ID) to the required flow rate. An undersized ID increases frictional losses and pressure drop, whereas an oversized ID reduces fluid velocity. Also, don’t forget to measure the outer diameter (OD) for fitting compatibility.

• Bend radius: check the manufacturer data for the minimum bend radius. Rigid or cold hoses typically require larger radii to prevent collapse, cracking, or fatigue.

Temperature

Again, there are three elements relating to temperature that you should consider: fluid temperature, the ambient temperature, and the temperature gradient.

• Fluid temperature: start by checking both the continuous operating temperature and any short-term spikes. Some hoses can withstand brief surges better than sustained exposure. Always compare these against the hose’s maximum service temperature.

• Ambient temperature: next, think about external conditions which can affect flexibility and cover resilience. If your hose will exist in sub-zero temperatures during the winter or have to withstand solar heating outdoors, make sure it is up to the task before purchase.

• Temperature gradient: lastly, don’t forget about temperature fluctuations. Long runs and uneven temperatures can induce differential expansion. Integrate expansion loops or flexible sections to mitigate stress.

Application

What is the intended purpose of your steam hose? This will determine what regulatory standards, mechanical hazards, and installation constraints befall it.

• Regulatory standards: check your hose is compliant with relevant certifications, such as FSA for food, FDA for hygienic steam, ATEX for explosive atmospheres, or PED for European pressure equipment.

• Mechanical hazards: consider and assess the risks your hose will be subjected to, such as abrasion, crushing or impact. In harsh environments, reinforced or armoured covers prevent accelerated wear.

• Installation constraints: don’t forget to factor in space limitations, routing around machinery and the desirability of quick-connect assemblies for rapid change-out.

Medium

Next, think about what medium will your steam hose transport, particularly the quality of steam, any exposure to chemicals, and additional particulate matter.

• Steam quality: EPDM rubber hoses are typically suitable for saturated steam. For superheated or supercritical steam, choose PTFE or metal hoses to resist vulcanisation.

• Chemical exposure: if steam carries corrosive condensates or additives, go with hoses with PTFE liners or stainless-steel cores.

• Particulates: in the presence of limescale or debris, smooth-bore PTFE hoses reduce build-up and simplify cleaning.

Pressure

How much pressure does your steam hose have to contend with? This includes the working, and burst pressure, as well as how flexibility will impact the pressure.

• Working pressure: you need to select a hose rated at least 25% above your system’s maximum operating pressure to accommodate for pressure surges.

• Burst pressure: make sure the burst rating is at least four times the maximum working pressure, to align with safety regulations.

• Flexibility vs pressure: higher pressure ratings often require more reinforcement, which reduces flexibility. Balance pressure containment needs with manoeuvrability requirements.

To make things easier for you, we’ve added material–media compatibility table below for quick reference points.

Steam hose fittings and connections

Selecting the right fittings and connections is as important as choosing the hose itself. Incorrect or mismatched fittings can lead to steam leaks, pressure loss or even dangerous blow-offs. We’ve listed the key aspects you should look out for when buying hose fittings and connections:

Hose ends

Hose ends must match both the hose’s outer diameter and the mating equipment’s inner diameter. Common hose-end styles include:

• Crimped ferrule ends: the fitting is mechanically swaged onto the hose, offering a permanent, high-pressure seal.

• Swaged ends: hydraulic pressure deforms the fitting around the hose, which is ideal for continuous, vibration-prone services.

• Threaded screw-on ends: useful for moderate pressures and applications requiring periodic hose changes.

• Flanged ends: provide robust sealing surfaces for high-pressure systems and simplified disassembly.

• Push-on quick couplings: allow rapid hose changes in cleaning or batch-processing environments.

Connectors

Beyond the hose end itself, the mating connector must have a secure, leak-tight interface. Popular connection methods include:

• Camlock couplings: fast, tool-free assembly widely used in steam-cleaning and transfer operations.

• Victaulic (grooved) couplings: clamp around grooved pipe ends, combining alignment ease with high-pressure performance.

• Threaded unions and nipples: these offer simplicity, but require careful torque control to prevent over-tightening.

• Flange unions with gaskets: these enable precision alignment and easy access for inspection or replacement.

• Clamp-style fittings: high-temperature gaskets (e.g., PTFE or graphite) are favoured in hygienic and chemical-processing plants.

When specifying fittings, confirm that all metallic components are rated for your system’s maximum working pressure and thermal cycling requirements. 

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Safety and maintenance advice

As with any hose type or connector, safety is paramount. 

A single hose failure under pressure can cause severe injuries, equipment damage and costly downtime. 

Therefore, regular inspection is vital to detect wear before it escalates into failure. You should take time to implement a visual and functional inspection regime, including:

• Daily visual checks: look for cracks, cuts, or abrasions on the cover. Inspect fittings for corrosion or deformation.

• Pressure test intervals: carry out hydrostatic or pneumatic tests at intervals defined by manufacturer guidelines or internal safety policy.

• Fitting examination: check crimped or swaged connections for signs of slippage, corrosion, or sealant degradation. Tighten threaded fittings to the specified torque.

Steam hoses encounter several deterioration mechanisms. Understanding these allows targeted preventive measures.

Find the best steam hoses and fittings at The Hosemaster

At The Hosemaster, we stock a huge range of steam hoses and fittings that have been thoroughly tested for use, to provide additional assurance that the hose will perform reliably under extreme conditions.

We have decades of experience within the hose industry, which means you not only have access to superb supplies, but also expert advice when you require it. If you have any further questions, you can get in touch with our team online, or give us a call on 01282 604 002.

Shop the best steam hoses at The Hosemaster today

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