water tube steam boiler in singapore has a large demand. most of singapore industry buy oil gas water tube steam boiler, some buy biomass fired steam boiler. the opposite steam boilers structure are firetube steam boilers.today, we mainly talking about water tube steam boiler design in singapore market.
Description of water tube steam boilers including operation, types and benefits; also, a brief synopsis on how they are applied to combined heat and power generation.
Water-tube steam boiler design
Water-tube steam boilers differ from shell type steam boilers in that the water is circulated inside the tubes, with the heat source surrounding them. Referring back to the equation for hoop stress (Equation 3.2.1), it is easy to see that because the tube diameter is significantly smaller, much higher pressures can be tolerated for the same stress.
Water-tube steam boilers are used in power station applications that require:
A high steam output (up to 500 kg/s).
High pressure steam (up to 160 bar).
Superheated steam (up to 550°C).
福彩快3下载 However, water-tube steam boilers are also manufactured in sizes to compete with shell steam boilers.
Small water-tube steam boilers may be manufactured and assembled into a single unit, just like packaged shell steam boilers, whereas large units are usually manufactured in sections for assembly on site.Many water-tube steam boilers operate on the principle of natural water circulation (also known as ‘thermosiphoning’). This is a subject that is worth covering before looking at the different types of water-tube steam boilers that are available. Below Figure helps to explain this principle:
Cooler feedwater is introduced into the steam drum behind a baffle where, because the density of the cold water is greater, it descends in the ‘downcomer’ towards the lower or ‘mud’ drum, displacing the warmer water up into the front tubes.
Continued heating creates steam bubbles in the front tubes, which are naturally separated from the hot water in the steam drum, and are taken off.
However, when the pressure in the water-tube steam boiler is increased, the difference between the densities of the water and saturated steam falls, consequently less circulation occurs. To keep the same level of steam output at higher design pressures, the distance between the lower drum and the steam drum must be increased, or some means of forced circulation must be introduced.
Today, we introduced our water tube steam boiler, next time we will talk about water tube steam boiler sections. More information about water tube steam boiler in Singapore, contact us with: firstname.lastname@example.org. Or leave message below: