Watertube Boilers
Water Tube Boilers A water tube boiler is the opposite of a fire tube boiler. Water flows through the tubes and that are incased in a furnace in which the burner fires into. The tubes are connected to a steam drum and a mud drum. The water is heated and the steam is produced in the upper drum.
Water Tube Boilers Large steam users are better suited for the water tube boiler. The industrial water tube boilers are typically used for producing steam or hot water for large industrial process applications. Water tube boilers are usually not used for heating applications.
Water Tube Boilers Reasons for changing from Fire Tube Boilers to Water Tube Boilers Larger Capacities up to several million lbs/hr. Higher Pressure and Temperature Steam up to 5,000 PSIG. More Compact Faster Responding to Load Changes
Water Tube Advantages Less weight and space for the amount of steam generated Flexibility when raising steam and answering sudden changes in steam demand More adaptable for higher pressures and temperatures than the fire tube boiler Better heat transfer characteristics resulting in higher boiler efficiency Less danger of injury to personnel from an explosion
Water Tube Boiler Disadvantages The requirements for the use of pure water The need for constant skilled supervision during operation Higher initial cost Higher maintenance and repair costs on bent tube designs
Types of Water Tube Classifications Number of Steam and Water drums Drum arrangement Arrangement of tubes Types of headers Water Circulation Number of gas passes Superheater location Superheater heat transfer method
Number of Steam and Water Drums Single Drum (Header Boiler) or Auxiliary Boilers Two Drum “D” Type Boiler Three Drum “A” Type or “M” Type Boilers
Header Type Boiler Safety Valve Steam Drum Exhaust Furnace Rear Header Forward Header Source: www.steamesteam.com
A-Type Water Tube Boiler Source: www.steamesteam.com
A-Type Water Tube Boiler Header Source: www.steamesteam.com
M-Type Water Tube Boiler Source: www.steamesteam.com
D Type Water Tube Boiler Source: www.steamesteam.com
D-Type Water Tube Boiler Source: www.steamesteam.com
D-Type Water Tube Boiler Source: www.steamesteam.com
D-Type Water Tube Boiler Source: www.steamesteam.com
D-Type Water Tube Boiler Source: www.steamesteam.com
Drum Arrangement Cross Drum if the drum is at right angles to the tube bank Longitudinal Drum if the drum runs in the same line as the tubes that make up the tube bank
Types of Headers Box type headers Sinuous type headers Circular type headers
Water Tube Boiler Headers
Water Tube Boiler Headers
Arrangement of Tubes Straight tube boilers Bent tube boilers with tubes inclined or vertical
Water Tube Boilers Source: www.steamesteam.com
Water Circulation Natural Circulation Accelerated Circulation Forced Circulation
Number of Gas Passes Single Double Triple Depending on the number of times the combustion gases pass through the generating tube banks
Superheater Location Pertaining to the positioning of the superheater Overdeck Interdeck Underdeck
Superheater Heat Transfer Method Convection Type Radiation Type Radiation-Convection Type
Auxiliary Boilers Source: www.steamesteam.com
Auxiliary Boilers Source: www.steamesteam.com
Auxiliary Boilers Source: www.steamesteam.com
Auxiliary Boilers Source: www.steamesteam.com
Auxiliary Boilers Source: www.steamesteam.com