Thermal insulation solutions for power plants

– To provide customers with the most professional thermal insulation solutions –

– Plant introduction –

Thermal power plant, referred to as thermal power plant, is the use of coal, oil, natural gas or other fuel chemical energy to produce electric power plants. The generator set of thermal power plant is composed of boiler, steam turbine and generator and many auxiliary equipment pipelines.

– Thermal insulation materials are commonly used in power plants –

External insulation materials: aluminum silicate fiber blanket, rock wool, glass fiber wool, silicate board, felt, tube shell, board, cloth, calcium silicate board, tube shell, aerogel composite insulation blanket.
Other refractory materials: acid resistant castable, wear resistant castable various weight castable, firebrick, thermal insulation brick.

– Power plant insulation system area insulation solution –

The key of thermal insulation of power plant is to divide it into three main parts according to the application area, and then design the thermal insulation scheme respectively.

• Thermal insulation solution for boiler body of power plant

Power plant boiler, including boiler body and some auxiliary equipment. After the fuel is burned in the boiler chamber, it gives off heat energy. Through the heat transfer on the metal wall, the water in the boiler is transformed into superheated steam with certain pressure and temperature. Then the steam is sent to the steam turbine, which drives the generator to generate electricity.
The superheated steam in the boiler is at 540℃.

1> insulation scheme for boiler body of > power plant

The insulation layer is mainly composed of high-temperature anti-corrosion coating (anti-corrosion layer) +100mm rock wool felt or fiber blanket (insulation layer) + galvanized flexible wire mesh (binding layer) + coated fabric (surface layer) + ceramic fiber blanket cloth (protective layer B) + glass fiber cloth (protective layer A) + aluminum powder heat-resistant paint (surface layer).

2>Other parts of the power plant boiler system insulation structure selected materials

Boiler water wall: alumina brick + rock wool board
Furnace top cover insulation: ceramic fiber + rock wool board
Top insulation of furnace top cover: refractory castable
Furnace box: ceramic fiber board, ceramic fiber blanket
Drum: ceramic fiber blanket + rock wool board
Drop tube: ceramic fiber board, ceramic fiber blanket + rock wool board
Furnace wall at smoke corner: ceramic fiber module, ceramic fiber blanket + rock wool board
Air preprocessor: ceramic fiber board, ceramic fiber module, ceramic fiber blanket + rock wool
Boiler hot air duct: ceramic fiber blanket + rock wool
Boiler body flue: ceramic fiber module, ceramic fiber blanket + rock wool
Electric dust removal: rock wool board

• Steam turbine thermal insulation solution

Steam turbine is a kind of rotating power machinery, its main task is to convert steam heat into mechanical energy.

It is very important for the thermal economy and long-term operation safety of the steam turbine thermal insulation equipment whether the structure design is correct and reasonable and whether the thermal insulation materials are chosen appropriately.

In the past, some power plants and shipyards, due to unreasonable structure design of thermal insulation devices and improper selection of thermal insulation materials, have large temperature difference between upper and lower cylinders, large temperature difference between inner and outer cylinders and flange walls during operation of the units, resulting in serious deformation of the units and affecting the safe operation of the units.

Some power plants, shipyards and industrial steam turbines in China have been gradually replaced by new detachable thermal insulation structures. The lower cylinder adopts fixed insulation structure.

Thermal insulation scheme of steam turbine of the power plant:

1>Upper cylinder: detachable insulation sleeve + outer protective layer (stainless steel plate or glass fiber reinforced plastics), made by partition and block.

Heat preservation jacket inner layer — high-temperature ceramic fiber cloth (resistant to 1260℃, can be used at 1000℃ for a long time) or high-silicon oxygen cloth (resistant to 1000℃, can be used at 950℃ for a long time);

Insulation sleeve Insulation inner core layer: ceramic fiber blanket 240mm;

Outer layer of insulation sleeve – silicone cloth.

2> Lower cylinder: Fixed insulation structure (similar to boiler body insulation), insulation thickness is 1.1 times of the upper cylinder.

3> Cylinder middle parting flange: detachable insulation sleeve + outer protective layer (stainless steel plate or glass fiber reinforced plastic), partition, block production.

Different insulation materials can be changed according to the actual application conditions, so as to change the thickness and size to meet the insulation installation of the tight space between the equipment.

• Thermal insulation scheme of steam pipe of power plant

It adopts detachable thermal insulation structure and the insulation layer thickness is 180mm (90mm ×2 layers ceramic fiber blanket).

Inner layer of insulation jacket — medium alkali glass fiber cloth (resistant to 600℃, can be used for a long time at 450℃);

Insulation sleeve Insulation inner core layer: ceramic fiber blanket 180mm;

Outer layer of insulation sleeve — silica gel cloth/reflective cloth.

Three different temperature pipes correspond to different inner thickness of insulation.

Removable insulation cover (package) is a new generation of thermal insulation flexible insulation products, its biggest feature is detachable, reusable, to meet the need for regular maintenance or maintenance of high temperature work body insulation.

– Steam turbine adopts detachable insulation sleeve after advantage –

• Low thermal conductivity, good thermal insulation effect;
• Save the construction time during installation and maintenance, greatly shorten the construction period, and indirectly create profits;
• It can be dismantled for many times, reused, energy saving and environmental protection.
• Flexible insulation, not afraid of stepping, not afraid of touching;
• The outer surface is oil-proof and water-proof, acid-proof and alkali resistant.
• A variety of ways to choose, easy installation without bare;
• The appearance of the product is beautiful and clean, the surface can be swabbed.
• The service life is up to 20 years.