Replacing Radiant Tubes for Furnaces

Radiant tubes can last anywhere from one to five years depending on the furnace and how it’s used. As you look ahead to your next radiant tube replacement, you might be wondering exactly how to improve efficiency or extend their life. You might also be looking to avoid a premature failure that can cause a host of production delays.

We’ve compiled a short list of points that every maintenance manager should keep in mind as you’re planning to replace radiant tubes for your heat-treating furnace.

Tip #1 – Fabricated designs are successful alternatives to cast designs

It’s a common misconception that cast radiant tubes outperform fabricated radiant tubes. Although every furnace and manufacturing process is different, the fabricated option can potentially outperform a cast design.

Remember that castings are heavier, more brittle and prone to breakages. The heavier walls result in less heat transfer during your manufacturing process. And breakages leave you susceptible to experience products of combustion entering your furnace which then contaminates your product. You also need to be more aware of the support methods you use within the furnace due to the weight of cast tubes.

Fabricated versions have several advantages because they are lighter and have thinner walls. As a result, they provide better heat transfer, they are more ductile, and are less likely to fracture. Because they are lighter, fabricated radiant tubes are much easier to install and place less strain on the supports.

In addition, fabricated tube return bends, flanges, bungs, and straight components can be repaired or replaced on site. This can be a great time saver. Don’t assume that replacing your radiant tubes with the same castings you’ve been using for years is your best option. It’s smart to explore how a fabricated design can improve your operations.

Tip #2 – The investment in fabricated radiant tubes is comparable (or better) to cast tubes

If you’ve considered fabricated tubes, you might have been hesitant because of the initial investment. However, the up-front cost for each option is comparable. Cast tubes might have a slight advantage, but the higher weight coupled with longer lead times makes cast tubes less appropriate in most applications.

If you look beyond the initial investment and consider how fabricated tubes can help you achieve more consistent heat transfer, maximum efficiency and longevity, then you might find that investing in fabricated radiant tubes is your best option.

Tip #3 – Smart maintenance managers start on re-designs early

When your company starts planning for radiant tube replacement, it’s best to have maintenance and purchasing  work together to identify what’s most important to your operation so you can make a smart purchase. These conversations take time and shouldn’t be rushed. You’ll want to consider factors such as the typical lifespan of your radiant tubes and which failure points apply to you.

If you pursue a re-design, you’ll be exploring several key elements. The biggest one is cast versus fabricated radiant tubes. We have a full article comparing cast versus fabricated that goes into more detail that’s worth reading.

Tip #4 – Consider technology that can further improve efficiency

Here at Alloy Engineering, we’ve conducted third party testing of our Helios™ SurfaceMax™ and found a 4% increase in efficiency. The tubes fit into existing bungs with no furnace modifications required. With the ability to increase furnace throughput, manufacturers can see significant profitability increases in the short and long-term.

When it comes time to replace your radiant tubes, don’t be afraid to explore new options that could improve your operations. Find a vendor you can trust and start planning as early as possible.

Alloy Engineering fabricates tubes in any configuration and wall thickness and supports all furnace OEM tube designs. To learn more, contact us here or call us at 440.243.6800.