Boilers used in large heating systems, as a rule, are produced without a shielding coating. This is due to the fact that they are manufactured in accordance with the parameters of the boiler room. The lining of the boiler serves as a protective coating and is made from materials that provide the necessary characteristics.
Varieties
The main purpose of the protective layer is to reduce the level of heat loss and the risk of burns for workers, and energy costs are also reduced. Particular importance is given to the materials used to create the lining, and the technology of formation. There are several basic schemes, each of which is selected individually and has a high level of efficiency:
- The boiler lining is made of lightweight concrete, which has thermal insulation properties. With the help of chromite mass and special plates, the outer layer is made.
- The frame scheme incorporates three layers: mineral wool, diatomaceous concrete and fireclay concrete.
- Heavy haslimited scope and is only suitable for boiler rooms with a maximum temperature level of 800 degrees. The outer layer is red brick, the inner layer is a refractory brickwork.
Features
Bricking of hot water boilers is a labor-intensive process that requires adherence to technology and proper selection of material. Stuffed compositions are produced on a corundum, carbundum or chromite basis. Liquid glass often acts as a binding base. The amount of mass produced depends on the surface to be treated and the required thickness.
The composition applied to the surface is covered with a special grid made of refractory material. Sealing coating is carried out with magnesite, asbestos or fireclay powder. It should be noted that coating can be performed if the mass has not yet hardened.
What you need to know
Bas alt fiber, which is highly resistant to temperature, is used to form thermal insulation boards.
In some cases, it becomes more rational to partially lay the boiler. Reducing the loss of thermal energy and ensuring the safety of maintenance personnel is possible due to the processing of the doors of the structure. In this case, it is necessary to pay attention to the temperature distribution during cooling.
Repair of the lining of the boilers begins with the dismantling of the piping, while it is desirable to save the base of the structure for future use. In the presence ofuneven areas on screens and pipes can be applied with a layer of heat insulator. The service life of the structure can be increased by using aluminum coloring compounds used as a topcoat.
DKVR boilers
Systems of this series are designed to ensure the preparation of heated water and heat supply. They produce saturated steam and are often used in ventilation systems. The design has distinctive features in the form of vertically placed pipes and two drums. Boilers of this brand have many positive aspects:
- wide power range;
- use of any kind of energy source, including fuel oil and gas;
- automated system operation;
- assembly of the structure can be carried out in the boiler room, without the need to dismantle the walls;
- Bricking of DKVR boilers is made from any materials suitable for the intended mode of operation;
- reliability of the aerodynamic and hydraulic system ensures a high level of efficiency.
Boiler lining: technology
A mandatory step before bricking is a hydraulic test of the boilers. Next, the lining of the boiler surface and the outer lining are carried out. The lining materials used must be refractory and fireclay powder, sand and clay must be thoroughly sieved before use. Cement, refractory and red clay should not contain foreign inclusions, lumps and small debris.
Beforethe beginning of work, it is necessary to prepare a refractory mixture, tools and bricks of the same size. Each row of masonry must be checked with a building level to prevent the formation of depressions and bulges. You can verify the quality of laying the corners with a steel square. As it becomes clear, the laying of steam boilers is a rather complicated process that requires compliance with all norms and rules, so you can only take up work if you have knowledge and relevant experience. In most cases, it is better to turn to specialists, since even a minor flaw can lead to serious consequences in the future.
Features
The insulating layer must be free of cracks and chips. Before laying refractory fireclay bricks, it is sorted, the material must be of the same size without damage. The use of broken or cracked bricks is strictly prohibited, as this significantly reduces the strength of the structure. Rough edges also reduce the tightness of the seams.
Solution
Equally important is the mixture used for masonry. It should have a uniform structure without inclusions. For laying fireclay bricks, a solution based on clay and fireclay powder is suitable. The degree of fat content of clay determines the amount of powder. It is worth noting that s alt and river sand cannot be added to the composition, despite the fact that such ingredients are often found in mortars for laying furnaces.
Thicknessthe mixture during complex brickwork should be within 2 mm; with normal masonry, an increase of up to 3 mm is allowed. The result obtained directly depends on the observance of the proportions of the ingredients and thorough mixing. The consistency should be of medium thickness. The solution is mixed only with clean water, this guarantees the absence of lime and other impurities. It is recommended to prepare the composition in a separate, previously cleaned container.
Water boiler lining: description
Before starting work, all used elements must be cleaned of drops of solution, corrosion and contamination. The connection points of the reinforcement are connected with a wire with a diameter of about 2 mm or welded using electric welding. The use of aluminum and copper wire is undesirable.
Bitumen is applied in an even layer on the reinforcement and fixing elements necessary to strengthen the concrete.
For the manufacture of formwork, softwood is used, with the exception of larch. The sides adjacent to the concrete solution are carefully processed and planed. It is possible to use paper or clay with high plasticity to seal cracks in the formwork. Double formwork is suitable for laying a vertical surface or an angle of at least 40 degrees. It is recommended to cover the wooden surface with a lubricant in order to avoid its adhesion to concrete. A solution of water and mineral oil can be used as a lubricant.
Kilns and boilers in industry today remainirreplaceable objects, so often there is a need for repair and modernization of such structures. In addition, the brickwork of the boiler must be carried out and, if necessary, replacement of elements that have failed.
