Details Introduction about Water Tube Steam Boiler
Water-tube steam boilers differ from shell type boilers in that the water is circulated inside the tubes, with the heat source surrounding them. Referring back to the equation for hoop stress , it is easy to see that because the tube diameter is significantly smaller, much higher pressures can be tolerated for the same stress.
Working Principle of D type Water Tube Boiler
The working principle of water tube steam boiler is very interesting and simple. Let us draw a very basic diagram of water tube boiler. It consists of mainly two drums, one is upper drum called steam drum other is lower drum called mud drum. These upper drum and lower drum are connected with two tubes namely down-comer and riser tubes as shown in the picture. Water in the lower drum and in the riser connected to it, is heated and steam is produced in them which comes to the upper drums naturally. In the upper drum the steam is separated from water naturally and stored above the water surface. The colder water is fed from feed water inlet at upper drum and as this water is heavier than the hotter water of lower drum and that in the riser, the colder water push the hotter water upwards through the riser. So there is one convectional flow of water in the boiler system.
Many benefits of water tube steam boiler
1.Long-term reliability
ZBG maintains the same cornerstone company values as we did in 1945 when
the first ZG water-tube steam boiler was patented. These values include a commitment to excellence, outstanding customer service, quality and continuous improvement, integrity, technology leadership,accountability and a commitment to our people.
2.Fast load response
2.5 in. (6.35 cm) tubes are spaced 1 in. (2.54 cm) apart. This provides a larger volume of water in our furnace walls and contributes to a faster load response. In addition, our uniquely designed drum internals can handle varying loads without circulation disruptions or carryover. Connections for lower drum heating coils are also standard.
3.Low operating and maintenance costs
The ZBG water tube boiler drives maintenance to a minimum with:
1.No reliance on refractory seals
2.2.Positive circulation, 100% water-cooled rear wall
3.A fully drainable superheater located in the convection bank 4.Galvanized, primed and enamel-painted exterior lagging
4.5.Hinged drum manways for improved waterside access
4.Controlled emissions
ZBG’s combustion design engineers work with outside burner suppliers to meet your stringent requirements. The elimination of floor brick gives our furnace more watercooled surface, thereby helping to meet today’s tough emissions limits.