SA210A1 Carbon Steel Boiler Membrane Wall Electrical Water Boiler Spare Parts

                      Membrane Type Boiler Water Wall Panel for Coal-fired Boilers

General Description: Boiler membrane water wall panel

Water wall panels are the main heating surface of boilers, composed of numbers of rows of steel tubes, arranged around the boiler corner. Inside is the flowing water or steam, and the outside accepts the heat of the flame in the furnace of the boiler, mainly absorbing the radiation heat of the high temperature combustion products in the furnace. The working fluid rises in it and evaporates by heat.

The full name is water wall tube, old name is water-cooled wall,also called riser. Usually laid vertically on the inner wall of the furnace, they are used to absorb the radiant heat by the flame and high temperature flue gas.They are the main form of heating surfaces for the various modern boilers, also the basic parts of water circulation circuit. For they have the functions of cooling and protecting the furnace wall, so called water wall panels.

When the water wall was initially designed, it was not intended to be heated, but to cool the furnace so that it would not be damaged by high temperature.Afterwards, because of its good heat exchange function, gradually replacing the steam drum to be the main heating parts for boilers. They are the evaporative heating surface consisting of many parallel tubes laid on the inner wall of boiler hearth. Their functions are to absorb the radiant heat by high temperature fire or gas flue in the furnace, and produce steam or hot water inside the tubes, and also reduce the furnace wall temperature so as to protect it. In large capacity boilers, the flame temperature in the furnace is very high and the intensity of heat radiation is very high. 40-50% even more of heat is absorbed by the water wall.Except small capacity boilers, the main evaporative heating surface for the present water tube boilers are the water wall.

Parameters

Advantages of Membrane Water Wall

(1) Ensure the sealing of furnace wall and reduce air leakage in combustion chamber.

(2)The realization of full water cooling in combustion chamber is beneficial to prevent coking under the condition of intensified combustion.

(3)The cooling time of start-up and shutdown of boilers can be shortened because of its small heat storage capacity, fast temperature rise and fast cooling in combustion chamber.

(4)Pipe-laying furnace wall is suitable, which greatly reduces the load of boiler frame and it is convenient for suspension and lifting.

(5)Compared with the bare tube type, the heat absorption capacity of the tube is improved.

(6)It improves the per-assembly degree of boiler components, facilitates and reduces the installation workload.

Classification

If according to the structure type, there are three main types: bare tube type, membrane type, and prick tube type.Bare tube type are composed of the whole row of seamless steel tubes with the simplest structure. Membrane water wall is a kind of joint welding of many rolled finned tubes of water wall to form a sealed combined heating surface. It can not only improve the air tightness of the furnace, reduce air leakage, but also protect the furnace wall, reduce the weight of the furnace wall and simplify the structure.The water wall of bayonet pipe is a kind of pin which is 20-25mm long and 6-12mm in diameter welded on the water wall pipe, and then coated with chrome ore sand refractory plastic to reduce the heat absorption at the water wall part and increase the temperature of combustion zone. It is suitable for the occasion where the fuel ignition is particularly difficult or some liquid slag discharge furnaces. According to the layout, there are two types of water-cooling wall; wall-attached type and partition type(i.e. double sided heating).The former is mostly embedded in the inner wall of the furnace wall, which absorbs heat on one side;the later is mostly installed in the middle of the large-scale boiler hearth, which divides the whole furnace into two separate parts and is heated on both sides.

Company Introduction

Established in 1985,Zhangjiagang Hua Dong Boiler Co.,Ltd.(trading as HD Boiler),produces power plant; industrial; waste heat; waste incineration; biomass; organic heat carrier and electric steam boilers. Coupled with a comprehensive range of heating surfaces, HD Boiler brings to the market a unique service including boiler design , fabrication, installation, maintenance and replacement of boiler pressure parts.