What Are the Different Types of Boiler Tubes?

Many steel pipes are used in boiler systems, but each pipe has a different position and function. We need to select suitable boiler tubes based on actual operating conditions. This involves many factors, such as pipe type, material, and manufacturing process, making the selection of appropriate boiler tubes a crucial issue.

Boiler Tube Comparison Chart

Boiler tubing is not a single product but rather composed of multiple components, and different components utilize different types of boiler tubing. If "the same grade of boiler tubing were used everywhere," the tubing would be excessively expensive for use in cold regions, but would be of insufficient quality and provide inadequate protection in high-temperature/corrosive areas.

Which tube material grade should I use—carbon, alloy, or stainless?

This is a frequently asked question.  To put it simply, we can understand it as: in which applications do we use which types of boiler tubes?

• Carbon steel boiler Tube is often used in cooler sections where metal temperature and corrosion risk are manageable.
• Low-alloy Cr-Mo steel Tube are often used as temperatures climb (common in hotter pressure parts).
• Austenitic stainless / high-alloy are often selected for the hottest superheater/reheater conditions.

These steel pipes also have their corresponding standards.

Seamless vs welded (ERW)—which should I specify for boiler tubes?

• Seamless boiler tubes are typically used in high-pressure, high-temperature environments and require heat circulation; they are sometimes highlighted in design drawings.
• In less demanding environments, we recommend ERW steel pipes because of their relatively lower cost. Of course, we will provide a complete quality assurance plan (including reports on non-destructive testing, water pressure/voltage testing, etc.).

How do we prevent boiler tube failures (and stop repeat leaks)

1. Control waterside chemistry to prevent scaling/corrosion

Waterside failures are frequently linked to scaling, corrosion, and chemical imbalance, which can drive localized overheating.
Actions that work:

Tighten feedwater/boiler-water control (TDS, oxygen control where applicable, consistent treatment program).

Track deposit indicators and clean proactively.

2. Manage fireside deposits/erosion/corrosion

Fuel ash, soot, and temperature gradients can damage external tube surfaces over time.
Actions that work:

Tune combustion, improve sootblowing strategy, monitor slagging/fouling patterns.

Consider tube material upgrades/coatings in known high-risk zones (guided by failure history, not guesswork).

3. Institutionalize inspection + root cause learning

EPRI and other industry guidance emphasizes formal programs that combine inspection, failure mechanism identification, and corrective actions to reduce repeat events.
Actions that work:

Baseline thickness measurements, targeted NDT in hot spots.

Keep a tube-failure “map” by location/type; treat repeats as a system problem, not a one-off repair.

Any more questions?

If you need information about your boiler type, tube location (economizer/superheater/water wall, etc.), and design temperature/pressure + fuel + water chemistry, TORICH can help you match appropriate tube standards and materials, prepare clear procurement specifications, and reduce the risk of recurring tube failures—allowing you to buy once, install once, and operate for a longer period.

Contact us now!