Boiler inspection 101: Fireside
When your boiler is open for inspection, the fireside tells a story — if you know what you're looking at. Here's exactly what to check and why it matters.
Jude walks through a fire tube boiler open for a Boiler University 301 class, covering welded tube ends, beaded tube ends, flared tube ends, what inspectors look for when peering through tubes, and how to identify cracking and distortion in the Morrison tube and tube sheet.
Missing signs of thermal stress, oxygen pitting, tube movement, or furnace cracking during an inspection can turn a minor repair into a catastrophic failure — and a very expensive one.
This inspection is happening live at Boiler University, WARE's hands-on training program where technicians and engineers get real classroom time on real equipment.
Learn more about Boiler University training and WARE's boiler services at wareinc.com.
Timestamps:
0:00 - Intro: Fireside inspection overview
0:29 - Welded tube ends: purpose and what to inspect
1:37 - Beaded tube ends: how they work and failure signs
2:22 - Flared tube ends and what leakage looks like
3:19 - Why inspectors look through each tube with a flashlight
4:23 - Pinhole leaks and oxygen pitting inside tubes
5:30 - Inspecting the Morrison tube and main furnace
6:20 - Thermal stress cracking on the furnace and tube sheet
Related search terms:
fire tube boiler inspection, boiler tube end types, welded vs beaded tube ends, Morrison tube inspection, boiler tube sheet cracking, boiler fireside inspection checklist, what causes boiler tube failure, oxygen pitting boiler tubes, boiler inspection what to look for, thermal stress boiler
Related Search Q&A:
What is the difference between a welded, beaded, and flared tube end on a fire tube boiler?
Welded ends add fixture and act as a thermal bridge to prevent
overheating. Beaded ends are rolled then folded back against the tube sheet for heat transfer. Flared ends anchor the tube mechanically and are used in lower-temperature passes where overheating isn't a concern.
Why does a boiler inspector look through each tube with a flashlight?
They're checking that the tube is still straight and symmetrical — a bent or drooping tube indicates overheating or low-water conditions. They're also looking for pinhole leaks, mineral deposits, or formations that signal early-stage tube failure.
What causes cracking in a boiler tube sheet or Morrison tube?
Thermal stress from rapid startup or shutdown, low water conditions, and scale buildup that blocks heat transfer are the primary causes. Cracks concentrate where the furnace tube meets the tube sheet.
What does oxygen pitting look like in a fire tube boiler?
Oxygen pitting eventually creates pinholes in the tube wall that allow water to weep into the fire side, often visible as mineral deposits or formations running down the inside of the tube.
What is a Morrison tube on a fire tube boiler?
The Morrison tube is the main furnace tube — the large corrugated or plain tube that contains the burner flame. Inspectors check it for bulging, collapse toward the burner, and cracking at the rear tube sheet connection.
Need boiler parts, valves, gaskets, or maintenance supplies? Visit BoilerWAREhouse: https://www.boilerwarehouse.com
Learn more about WARE boiler service, rentals, training, and support: https://www.wareinc.com
Want boiler training? Learn more about Boiler University and boiler operator education through http://www.boileruniversity.com
🔔 Subscribe for weekly boiler tips and deep dive technical content.
👍Like & share to help us elevate the steam industry.
👍If you found this helpful, like, subscribe, and leave your boiler questions in the comments.
© 2026 @wareboilers. All rights reserved. Unauthorized reproduction or distribution of this content is prohibited. Ware Boilers’ videos are intended for promotional purposes only and does not constitute professional advice. Please contact our boiler professionals via https://www.wareinc.com/ with specific questions or repair needs. You should not attempt any boiler repair or modification without first consulting with a licensed contractor and the manufacturer. Ware Boilers does not warrant the accuracy, completeness, or usefulness of information available on this YouTube page. Nothing contained in or provided in any of Ware Boilers’ videos is intended to constitute advice or to serve as a substitute for a licensed contractor’s inspection or manufacturer specifications. Any reliance you place on such information is strictly at your own risk.
Jude walks through a fire tube boiler open for a Boiler University 301 class, covering welded tube ends, beaded tube ends, flared tube ends, what inspectors look for when peering through tubes, and how to identify cracking and distortion in the Morrison tube and tube sheet.
Missing signs of thermal stress, oxygen pitting, tube movement, or furnace cracking during an inspection can turn a minor repair into a catastrophic failure — and a very expensive one.
This inspection is happening live at Boiler University, WARE's hands-on training program where technicians and engineers get real classroom time on real equipment.
Learn more about Boiler University training and WARE's boiler services at wareinc.com.
Timestamps:
0:00 - Intro: Fireside inspection overview
0:29 - Welded tube ends: purpose and what to inspect
1:37 - Beaded tube ends: how they work and failure signs
2:22 - Flared tube ends and what leakage looks like
3:19 - Why inspectors look through each tube with a flashlight
4:23 - Pinhole leaks and oxygen pitting inside tubes
5:30 - Inspecting the Morrison tube and main furnace
6:20 - Thermal stress cracking on the furnace and tube sheet
Related search terms:
fire tube boiler inspection, boiler tube end types, welded vs beaded tube ends, Morrison tube inspection, boiler tube sheet cracking, boiler fireside inspection checklist, what causes boiler tube failure, oxygen pitting boiler tubes, boiler inspection what to look for, thermal stress boiler
Related Search Q&A:
What is the difference between a welded, beaded, and flared tube end on a fire tube boiler?
Welded ends add fixture and act as a thermal bridge to prevent
overheating. Beaded ends are rolled then folded back against the tube sheet for heat transfer. Flared ends anchor the tube mechanically and are used in lower-temperature passes where overheating isn't a concern.
Why does a boiler inspector look through each tube with a flashlight?
They're checking that the tube is still straight and symmetrical — a bent or drooping tube indicates overheating or low-water conditions. They're also looking for pinhole leaks, mineral deposits, or formations that signal early-stage tube failure.
What causes cracking in a boiler tube sheet or Morrison tube?
Thermal stress from rapid startup or shutdown, low water conditions, and scale buildup that blocks heat transfer are the primary causes. Cracks concentrate where the furnace tube meets the tube sheet.
What does oxygen pitting look like in a fire tube boiler?
Oxygen pitting eventually creates pinholes in the tube wall that allow water to weep into the fire side, often visible as mineral deposits or formations running down the inside of the tube.
What is a Morrison tube on a fire tube boiler?
The Morrison tube is the main furnace tube — the large corrugated or plain tube that contains the burner flame. Inspectors check it for bulging, collapse toward the burner, and cracking at the rear tube sheet connection.
Need boiler parts, valves, gaskets, or maintenance supplies? Visit BoilerWAREhouse: https://www.boilerwarehouse.com
Learn more about WARE boiler service, rentals, training, and support: https://www.wareinc.com
Want boiler training? Learn more about Boiler University and boiler operator education through http://www.boileruniversity.com
🔔 Subscribe for weekly boiler tips and deep dive technical content.
👍Like & share to help us elevate the steam industry.
👍If you found this helpful, like, subscribe, and leave your boiler questions in the comments.
© 2026 @wareboilers. All rights reserved. Unauthorized reproduction or distribution of this content is prohibited. Ware Boilers’ videos are intended for promotional purposes only and does not constitute professional advice. Please contact our boiler professionals via https://www.wareinc.com/ with specific questions or repair needs. You should not attempt any boiler repair or modification without first consulting with a licensed contractor and the manufacturer. Ware Boilers does not warrant the accuracy, completeness, or usefulness of information available on this YouTube page. Nothing contained in or provided in any of Ware Boilers’ videos is intended to constitute advice or to serve as a substitute for a licensed contractor’s inspection or manufacturer specifications. Any reliance you place on such information is strictly at your own risk.
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