Is a Stainless-Steel Hose Worth it?

Stainless steel is extremely durable and more resistant to corrosive materials than other steel alloys. Stainless steel features more chromium than other forms of steel, which provides the alloy with its extra resistance and durability to weathering effects caused by elements such as water. The extra resistance and durability make our stainless hose products great tools for high-temperature and moisture present ducting applications.  As an added benefit, stainless steel duct is a timeless aesthetic choice which fits in well with a variety of different applications and environments. Some of these stainless hose applications include (but are certainly not limited to) use in brick kilns, chemical plants, diesel and engine exhaust, HVAC systems, and as general-purpose steel ductwork in construction sites, shipyards, and factories of all types. Some use this type of ductwork for its aesthetic qualities in faculties that have functional and artistic requirements.

Why use stainless-steel ductwork? Here are some of our favorite reasons:

• Corrosion resistance
• High tensile strength
• Highly puncture resistance
• Good Flexibility
•  Semi-rigid and will maintain shape when flexed
• Temperature resistance to up to 1650℉
•  Low-maintenance
•  Attractive aesthetics

What is a Stainless-Steel Flexible Hose Used for?

From automotive ducting to welding exhaust applications, our stainless-steel ductwork is ideal for working in extreme temperature environments.  One of the outstanding characteristics of stainless steel is its ability to maintain its durability and function in a wide range of temperature situations.  Our inventory of stainless hose products features various operating ranges with products that are capable of operating in temperatures as low as -400°F degrees Fahrenheit and withstanding temperatures as high as 1650℉ which is far higher than the melting point of aluminum. The excellent range of temperatures available make our flexible stainless-steel hose line an ideal option for moving high temperature exhaust fumes and chemicals. The titanium alloy of stainless hose infers that they are highly resistant to the damaging effects of corroding materials (namely, fumes and chemicals). This feature is what makes stainless ducting useful in exhaust ventilation of sulfur dioxide, hydrocarbons, and other types of automobile exhaust since they have little effect on the integrity of stainless steel.

“SSti-Flex 1650”

“Screw Clamps”

Is Metal Ductwork Better Than Flex?

This question assumes that metal ductwork cannot be flexed and that is incorrect. Our stainless ducting is flexible. The flexibility of stainless ducts is a function of their material makeup. They do not behave like vinyl flex ducts that cannot maintain their shape when flexed.  A standout feature of our stainless-steel ductwork products is their semi-rigid design.The semi-rigid design makes these flexible hoses self-supporting ducting, which is essential for ducting applications that require extra durability and stability. With a flexible SS hose you can bend the stainless hose in any direction that the application demands and the hose will remain in place without the need of an additional support system. This feature makes flexible SS hoses an economically efficient choice for heavy-duty applications that will require a hose to weave its way to an endpoint. In fact, that self-supporting ducting can be manipulated and put into position by hand means that you do not need potentially costly added elbows and connectors to create turns, bends, or shapes in your ductwork.  

“SS-Flex 800”

What is the Most Durable Material in Ductwork?

Stainless ducting has to be the most durable duct for most applications. When it comes to abrasion resistance stainless ducting is far more durable than vinyl, urethane, rubber or any other flexible ducting. Stainless steel is also known for its ability to resist the corrosive properties of many harsh chemicals. Our stainless-steel flexible hoses are extremely resistant to the types of chemicals frequently used in exhaust expulsion applications. Unlike other fabric and rubber flexible hose products, a ss flexible hose is extra durable when faced with high-temperatures and corrosive chemicals without sacrificing the flexibility demanded by many heavy-duty exhaust fume applications. Because of its longevity and innate damage resistance, stainless hose can be incorporated in a variety of sensitive applications or in places where access for regular maintenance or replacement would be difficult (such as in ceilings or underground conduits).

“SS-Flex 800”

Why does a Stainless-Steel Flexible Hose Last longer?

At both room temperature and elevated temperature, the material characteristics of stainless steel differ from those of carbon steel due to the high alloy content. At room temperature, stainless steel displays a more smoothed stress–strain response than carbon steel and no yield point. At elevated temperatures stainless steel generally exhibits better retention of strength and stiffness in comparison to carbon steel Stainless steels are most used for their corrosion resistance. The second most common reason stainless steels are used is for their high temperature properties; stainless steels can be found in applications where high temperature oxidation resistance is necessary, and in other applications where high temperature strength is required. The high chromium content which is so beneficial to the wet corrosion resistance of stainless steels is also highly beneficial to their high temperature strength and resistance to scaling at elevated temperatures. Chromium is an essential component of all stainless steels, making up a minimum of 10.5% of the alloy’s content. Chromium metal is valued for its high corrosion resistance and hardness. A major development in steel production was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. Stainless steel and chrome plating (electroplating with chromium) together comprise 85% of the commercial use.

“Stainless Steel Connectors”

What is 316Ti Grade Stainless Steel Ducting?

At its most basic level, stainless steel is an alloy composed mostly of iron. Iron on its own will rust, so stainless steel adds in chromium – at least 11% by volume – in order to stop oxidation and prevent rusting. Beyond that basic configuration, there is a large assortment of stainless-steel alloys with added parts carbon, nickel, molybdenum.

The most common grade of stainless steel used for your home’s cooking pans is 304, also known as 18/10. This refers to the 18% chromium and 10% nickel added into the steel.

316Ti is a higher grade which adds titanium and molybdenum to the alloy to increase its corrosion resistance properties. 316Ti is a variant of stainless steel that is alloyed with titanium. The addition of titanium to the steel gives it improved resistance to corrosion, particularly in environments with high temperatures and high concentrations of chlorides. The titanium content of 316Ti is typically around 0.5%.  316Ti is often used in the construction of heat exchangers, furnace parts, and chemical and petrochemical equipment. It is also used in the food and pharmaceutical industries, as well as in marine environments. The high resistance to corrosion makes it suitable for use in applications where the steel will be exposed to saltwater or other corrosive substances.

The mechanical properties of 316Ti are like those of standard 316 stainless steel, with a slightly higher yield strength and a lower elongation at break. The material is also non-magnetic and has a good weldability and formability.

So, how do you prevent metal leaching?  Increase chromium content: at 18% chromium, 316Ti is well above the minimum of 11%. The added titanium in the 316Ti alloy strengthens and stabilizes its chemical bonds, making it the best solution for resisting metal leaching.

Commonly Asked Questions About Stainless-Steel Hose Products

1. Do stainless-steel hoses rust?
   Some types of stainless-steel hose are more prone to corrosion than others, depending on the chromium content. The higher the chromium content in the flexible hose, the less likely the flex duct will rust.  Although stainless steel is a superior metal for your outdoor use because of its corrosion resistance, it is not maintenance-free. It is “stain less” or “stain resistant”, but this does not mean that it will never get stained, develop rust and corrosion if not maintained.
2. Does metal ductwork go bad?
   Yes, metal ductwork does corrode over time. There are different types of corrosion; uniform corrosion, pitting corrosion, etc… General corrosion occurs when most or all the atoms on the same metal surface are oxidized, damaging the entire surface.
3. Does metal ductwork rust?
   Flexible hoses made from metal do rust. Rust is a type of corrosion that occurs on metal surfaces when iron reacts with oxygen and water. The chemical reaction that causes rust is called oxidation.
4. Does stainless-steel hose last longer than aluminum?
   Aluminum is lighter, non-magnetic, malleable, has a  low density and is non-ferrous (does not contain iron.) Aluminum can handle up to +400℉ while variations of a SS hose can go up to 1650℉.
   Stainless steel ducts have high tensile strength, are low maintenance, heavier and stronger than aluminum. Aluminum is more affordable than stainless but has a shorter life cycle.
5. Can mold grow on metal ducts?
   Mold will grow in places with a lot of moisture. Metal ducts do not harbor mold or act as a source of diet. But if moisture is present inside a flex duct, and other conditions are ripe then mold will grow. Obvious sources are floods, roof leaks, problems with drainage or plumbing and include occupant-generated sources. Maintaining flex ducts and cleaning them if there is flooding is imperative.
6. How long do metal air ducts last?
   If metal ducts, aluminum or stainless, are well maintained they should have very long lives.
   Rusting and corrosion are undesirable effects that can ruin a metal’s ability to perform optimally. Flexible hoses that are in environments exposed to moisture, chemicals, and other corrosive substances and are not maintained will see damage.
7. Is a stainless-steel hose worth it?
   Stainless hoses are expensive, but they are used when fumes and elevated temperatures demand it.  Stainless ducting are worth it when the requirements demand a more sophisticated hose. For example, if an end-user is moving hot air that exceeds +750℉, then there are very few flexible hose options and stainless is a great choice.
8. Is stainless steel duct fire rated?
   Stainless steel, as a material, cannot be ignited and will not melt until it reaches a temperature of at least +2500°F.  Generally, fire rating is not needed for an SS flex hose. But fire will corrode stainless steel.
9. Should I replace metal duct with flexible?
   We don’t think you should replace your ductwork unless it is needed.  If your current ductwork is in good working condition, especially metal ducts, they should offer an excellent life cycle and do not need to be replaced by flexible PVC or other options.
10. What are the grades of stainless-steel ductwork?
    We offer two styles of SS flexible hoses:
    SS-Flex 800 which is a single-ply, helically corrugated stainless steel alloy wall hose construction with a four-ply finished seam that is folded flat and crimped for tightness and strength. Available in 5- and 10-foot lengths and with a temperature range of -400°F to +800°F
    SSti-Flex 1650 which is manufactured using 316Ti stainless steel in a patented roll lock. construction. Titanium stabilized 316 stainless alloy for superior high temperature corrosion resistance and this hose can handle temperatures of up to +2500°F
11. What is a stainless-steel flexible hose used for?
    Stainless-steel hoses are used to move high temps, ambient air, and chemical fumes.

“J-Lock Connectors”