At times it may be difficult to determine if steel pipe will be right for your particular application. There are many different types, grades and standards for stainless steel pipes and choosing the best one for its intended use can present several challenges. Other processes, such as welding, will present their own sets of variables, as will the physical environment of the application. For instance, will the pipe be indoors or outdoors, exposed to chemicals or harsh weather conditions? Knowing the answers to these questions will make the choice of appropriate pipe much easier.
Stainless steel is typically and widely used in many industries where its strength and corrosion resistance are invaluable. It is also used where heat and chemical resistance, cleanliness and lower maintenance costs are important. Whether you are a first-time designer or a highly-experienced construction engineer looking for a better type of material, the industry in which you work will most likely require a certain grade of stainless to be used.
There are several advantages and disadvantages involved when trying to determine if stainless steel pipes will be right for your chosen application. Most of these will pertain to your industry requirements (if any) for pipe in addition to the specific requirements that your application will have to meet. For example, the medical industry will necessarily have requirements that differ from the petrochemical industry due to sterilization, implant and device needs. Choices for piping materials can be numerous, especially with dozens of grades available in each type of material. Narrowing all of that down can be very stressful, so the pros and cons of these materials will be really helpful.
There are many advantages to each material irrespective of the intended application, including strength, weight, versatility and of course, cost. Some of the advantages of using steel pipe instead of other materials are strength, versatility and lack of reactivity to some chemicals. Stainless pipe also typically needs less preparation time before any assembly; carbon steel is normally coated before shipment as a protection and this protective coating has to be removed before any assembly or welding. Stainless pipe also is available as welded tubing, which is generally less expensive and more quickly available than seamless tubing, but the application requirements may prohibit the use of welded pipe as the seam was considered to be a weak area in the pipe. With improved manufacturing techniques in the last several years, a weld seam is much less of an issue than what it used to be. It is always a good idea to check for any pressure-related requirements or other pertinent issues before you choose between welded and seamless stainless pipe.
For some applications, aluminum pipe may seem to be a viable option. Compared to stainless, aluminum is much lighter and also corrosion-resistant. Stainless is, however, much stronger and easier to weld than aluminum. If heat conductivity is important, then aluminum will be the better choice. If food contact or reactivity is important, stainless pipe will be the better choice. For outdoor projects, stainless steel may be passivated to impart a thin layer of chromium oxide on its surface to impart a greater corrosion resistance, whereas aluminum will need to undergo a treatment such as powder coating or anodizing to help it withstand the elements.
Copper pipe has traditionally been used for plumbing because of its longevity and its ability to withstand a wide range of temperatures. On the other hand, copper is expensive and is usually cost-prohibitive when plumbing an entire house. It also requires a great deal of skill when assembling copper pipe since it has to be soldered to prevent leaks, and many DIYers simply do not have the necessary skill level for soldering the copper pipe that may be in their homes. Galvanized steel used to be used for plumbing, but its cost and tendency to leak around the threaded fittings have led to its discontinued use. In this type of scenario, stainless pipe is not the best option.
Today, various plastics are being used in many applications. Plastic pipe is valued for its ease of use and lower cost compared to many metals, but they also come with their own set of limitations. The lower strength of plastics eliminates their viability for use when the application or project necessitates a higher degree of strength and durability. Stainless steel pipe is therefore the better choice in these instances. While some plastic pipe can be used outdoors and even buried, it is also vulnerable to internal and external pressures which can cause it to crack and possibly break. Stainless pipe is considerably stronger and can accommodate higher pressures and temperatures with ease. When strength and durability are important, stainless pipe will be the better option for you. If your project requires that the hose be able to flex freely, then plastic pipe will work better, depending on the type of plastic.
Now that the basics have been covered, let us recap the pros and cons of using stainless steel pipe for your specific application. The advantages of using stainless pipe are strength, durability, relative cost, weldability and corrosion resistance. It is also a good choice in high-temperature environments and is resistant to UV radiation. These qualities make stainless steel pipe an obvious choice for many industries. Finishing operations can be performed to make the stainless pipe resistant to microbial growth, making it a very attractive (and usually required) choice for the food and beverage industry as well as wastewater treatment equipment since it has no reactivity with food and it is easily cleaned and sterilized. Stainless steel equipment also holds it resale value well in case your operational needs change.
The primary disadvantages to using stainless steel pipe include weight and sometimes cost, depending upon the amount of steel pipe required. If thermal conductivity is a necessary part of your project, then stainless steel pipe is not the answer. Several types of stainless steel are also vulnerable to corrosion caused by chlorides (such as in swimming pool areas) if the steel is not subject to immersion in the pool or if chlorine levels are not properly monitored. Careful choices will have to be made when selecting stainless steels for environments that are high in chlorides.
Despite the relatively few disadvantages of stainless steel as compared to other materials, stainless steel pipe is almost always an excellent choice for most applications in a very wide variety of industries. The high number of types and grades of stainless steel mean that almost any project will benefit from its use.