Advantages and disadvantages of watertube boilers

• Advatages over tank
  • Savings in weight of about 3:1 for a comparable heating surface area
  • Possibility of using higher temperatures and pressures without unduly increaseing wall thicknesses increases plant efficiency.
  • More efficient combustion space allowed
  • Greater flexibility of the structure and rapid circulation prevents the problems of thermal stressing in the tank boilers which leads to grooving. In water tube boilers roof and floor tubes are sloped at 15' to ensure circulation
  • thinner tube materials allow rapid steam raising and faster heat transfer rates
  • Saving in space for sam steaming rate
  • Wider safety margings- limited tube diameters and protected drum surfaces mean failure in tubes releases a flow of steam dependent on tube diameter
  • Thin tubes are easier to bend, expand and bell mouth
• Disadvatages
  • Lower reserve of water means a more efficient water level control is required
  • High quality feed required
  • little allowance to corrosion