We use a center symmetric three return structure design ideas, design capacity bigger three return steam boiler, the boiler’s biggest characteristics: center for all pressure parts and drum is symmetrical, boiler adopts full wet back structure, with great inner barrel and partial heart bad structure, it is beneficial to provide enough radiation heating surface. The convection heating surface is composed of a second return and a third return tube bundle. The front tubeplate of the backcombustion chamber of the low nitrogen gas boiler is connected with the furnace, and the back tubeplate of the backcombustion chamber is connected with the ellipsoidal head and tubeplate.
The second return and the third return turning smoke chamber of the series gas fired boiler constitute the front smoke box, the smoke temperature is lower than 500℃, therefore, the structure of the front smoke box adopts light structure of fire-resistant insulation material. The flue gas outlet of the rear smoke box is arranged along the longitudinal axis of the cylinder, which can not only shorten the length of the furnace body. The chimney can also avoid being placed in the direction perpendicular to the longitudinal axis of the cylinder. Condensate water corrodes the boiler body when the boiler starts and stops. The design of this boiler mainly considers the principle of boiler maintenance and stability.
The mixing device is set in the backwater inlet of the low nitrogen gas boiler. The backwater first scour the tube bundle of the smoke pipe and then contacts the furnace chamber, which improves the water temperature of the backwater contacting the furnace chamber. The phenomenon of local subcooling boiling is avoided. The boiler water flows in the lower part of the high temperature part of the combustion flue gas and the lower part flows in the upper part of the low temperature. In terms of thermal convection, the best structure design has been achieved. The steam boiler also achieves the maximum vaporization space, and the rear plate is added to cause the circulating water to flow through the high temperature surface of the backcombustion chamber, so that the reasonable and uniform heat transfer, to ensure the safe operation of the tube plate of the backcombustion chamber.
20 Tons gas fired boiler adopts waveform furnace, which not only strengthens the disturbance of flue gas, but also increases the radiation heat transfer area. At the same time, the stiffness of the furnace is increased, which effectively weakens the expansion stress of the furnace. The heat transfer effect is enhanced and the combustion of fuel in the furnace is promoted. The welding process of this series boiler tube and tube sheet adopts the advanced technology of pre-expansion, full welding, and then expansion. It not only prevents the corrosion of tube clearance, but also enhances the welding strength.
Low nitrogen gas boiler is easy to open, easy to repair and clean. This series of boilers have compact structure, convenient installation and transportation. After thermal debugging before delivery, it can run stably either on or in operation. This series boiler is equipped with imported water pump and burner, automatic program control, high degree of automation. Can make the boiler to achieve the best combustion effect. Zozen Boilers factory specializing in the production of various types of boiler products, over the years with many users to achieve friendly cooperation, welcome to come to consult and purchase!