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Water Tube Boiler

Can an OAB Replace Your Water Tube Boiler?

Water Tube Boiler

Water Tube Boiler & OAB Comparison

  Water Tube Boiler One Atmosphere Boiler
Equipment Costs Moderate/High Low/Moderate
Installation Costs High Minimal
Output per $ operating costs + certifications costs High Efficiency.  No certifications.
Upkeep/Maintenance Costs Moderate/High Low
Start Up Time Varies by particular unit and capacity. Expect a cold start up time of at least 15 minutes, with times ranging to over 30 minutes in some cases. OAB typically reaches temperature within 3-5 minutes of initial power.
Device Footprint Varies with output and temperature. Expect to utilize a minimum of 180ft^3 and a weight of over 300kg for a small unit. OAB unit footprint starts at ~2.5ft^3 and a weight of approximately 30kg.
Maximum Operating Temperature Varies with pressure. The highest pressure water tube boilers can reach temperatures of ~600°C. Typical water tube boilers will generate steam at around 110-150°C. OAB units are available in temperatures up to 1300°C.
Plug and Play Operations No. If boiler is moved, it must be reinspected. Yes. The OAB can operate anywhere if given water and power.
Portability No. Installed into a fixed location. Yes. Small size and light weight allows for relatively high mobility.
Safety (Can it Explode?) Water tube boilers can operate at pressures of over 10 atmospheres. The integrity of welds and construction materials are of utmost importance to ensure that they do not give way under such extreme pressures. One Atmosphere Boilers operate at one atmosphere of pressure. No pressurized boiler components are required, making operations significantly safer. If the OAB breaks, it will simply burn out and stop working, not explode.
Energy Efficiency Standard water tube boilers typically approach an 80% conversion efficiency rate from input to output energy. With additional economizers and investments, this number can improve to 85-87%. OAB outlet to output energy efficiency is over 95-99%.
Non-Productive Idling Time The majority of water tube boilers do not produce on demand steam, meaning they need to be idled even when there isn't an immediate demand for steam. This can lead to a nearly 30% decrease in overall boiler efficiency.  Instantly powering down the OAB is feasible in many situations when there isn't a short term demand for steam. The OAB's rapid startup allows for easy on-lining of capacity.  On Demand Steam.
Mandatory Certifications Prescribed? Most likely the answer is yes because of pressure and/or fire codes. All 50 states seem to require require boiler inspections for initial installations. No mandatory codes. Because the OAB doesn't have a high pressure vessel, it requires no special certifications.
Annual Inspections Most likely the answer is yes because of pressure and/or fire codes The majority of states require annual, bi-annual or quarterly boiler inspections. Non-compliant boilers will be immediately disabled. No. Wear and tear such as scaling and corrosion may occur in the OAB, but do not pose an immediate danger to safety, just device operation.
Extensive Operator Training Yes. Issues such as running the boiler dry pose a high risk to safety. A number of other incorrect operating procedures can lead to boiler damage and/or loss of life.

No. Enclosed units require a water inlet, power source and directing the steam output.

Several interlocking safety features are nonetheless included for OAB's.

Safety Training High. Proper operating procedures are vital to ensure safety. When improperly operated, high pressure boilers can be extremely dangerous. Moderate. OAB safety training primarily involves the risks of being burned by superheated steam and how to safely direct the steam output.
Click Here to Find Out More About MHI's One Atmosphere Boiler

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