important component in the boiler system is chimney flue pipe for boiler are an essential part of the design. The main task is to bring the combustion products into the atmosphere. As a result of combustion of fuel toxic gases are formed. The chimney should ensure their good dispersion, and have a natural draft.
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- sequence of calculations chimney
- Competent calculation chimney height: the success of the boiler
- Types of pipe for the chimney boiler
- Necessary precautions: lightning boiler
- chimneys Development for boiler( video)
sequence of calculations chimney
efficiency of the boiler depends on the traction and for which installation is done chimney. Therefore, the calculation is suitable with particular attention.
The design of the pipe passes according to the established requirements of SNiP.Calculate qualified specialists who have a special education.
only correctly calculating draft chimney installation can be sure of the efficiency of the boiler
miscount can cause accumulation of the gas mass inside the tube and cause an explosion.
Obligatory requirements are calculation of a chimney for observance of ecological cleanliness and safety. To calculate the project you need to determine the type of construction and the volume of fuel burnt.
Preliminary calculations:
- Calculate the aerodynamics of the chimney from the wind load;
- Take into account the height and diameter of the pipe in accordance with the combustible fuel;
- For the strength of the structure, calculate the thickness of the chimney walls;
- Determine the fixing method;
- Draw a drawing, an estimate and technical documentation.
Having defined the type of construction, it is necessary to make an aerodynamic calculation based on the indicator and the type of thrust, as well as the average annual wind load.
competent chimney height calculation: the success of the boiler
stack height is calculated based on the sanitary norms imposed on commercial and factory enterprises. The more hourly fuel consumption, its ash content and sulfur content, the higher the chimney should be.
In calculating the height of the pipe is very important to consider the power boiler and the material of construction
On chimney dimensions affects manufacturing material:
- to brick structures height ranges from 30 to 70 meters, with a diameter of 60 cm;
- Reinforced concrete chimney is limited to 300 meters;
- Other constructions can not be higher than 30 m.
The height of the house pipes is determined taking into account the aerodynamic calculation. For attached boiler houses, the height of the chimney's mouth should be above the wind back for at least half a meter. If within a radius of 10 meters there are taller buildings, then the end point must rise 2 meters above the roof of the building.
The optimum height of the pipe depends directly on the capacity of the boiler house, for example: with a boiler output of 500 kW, the length should be at least 11 meters, at 5000 kW - 20 meters, at 10,000 kW - 27 meters.
Incorrectly calculated height can affect the combustion process and cause a lot of problems: wind gusts can extinguish the furnace, poor draft can interfere with the normal operation of the boiler room.
In addition to the height of the pulling process, the diameter of the pipe is affected. Too wide a cross section will not allow the gases to rise up without hindrance. When calculating the diameter, take constant parameters of the velocity of the gases. For natural draft, they correspond to 20 m / s, with artificial traction, the indicators reach 30-40 m / sec, depending on the height of the chimney.
Types of pipes for the chimney of the boiler house
House chimneys consist of a foundation, a basement and a chimney. The process of construction takes place in stages. First install the foundation, lay the basement part and mount the pipe. It is not recommended to change the stacking system.
The variety of house pipes allows them to be arranged on different constructions.
The dimensions of the chimney are influenced by the materials from which it is made. Pipes are made of bricks, concrete, metal, fiberglass.
Depending on the location, the chimneys are divided into the following types:
- Self-supporting, detached structures, mainly used for large boiler rooms, installed using an anchor basket on the foundation.
- Facade, designed for fixing on the walls of the building with special tools and clamps. Most often installed in private sectors for fireplace or furnace traction.
- Fermats, based on special frames. The construction of the truss consists of metal beams, which is attached to the anchor basket, which is embedded in the foundation. Installation of the structure is carried out on the ground with subsequent lifting of the sections.
- Mast, metal trunks fixed with iron ropes. Such pipes are placed in the city. They are characterized by a high altitude.
All chimneys are equipped with staircases with handrails and platforms for repair and maintenance of the pipe. After installation of the design work is taken commission.
Safety precautions required: lightning protection of the boiler room
Lightning protection must be present for all non-metallic structures. Metal lightning receivers are inserted into the pipes and grounded by a current lead - a steel rod with a diameter of 1.2 mm, which is attached to the wall of the pipe by means of brackets. The grounding is terminated by a metal pin, driven into the ground.
Pipe earthing is a necessary security measure against lightning
According to the installation instructions for lightning arresters for boilers, their number depends on the length of the chimney. For a 15-50 meter construction, only one rod will suffice. Higher pipes up to 150 meters require the installation of 2 lightning conductors of meter height. Over 150 meters - at least 3 current leads.
In reinforced concrete structures, protruding fittings that are correctly connected at the highest point of the pipe can act as lightning arresters. After this, there is no need to additionally install an external current collector.
The metal structure acts as a natural pantograph and does not need protection.
Development of chimneys for boiler houses( video)
All calculations of pipes are carried out by specialists in accordance with the norms of SNiPa, after the design design is approved, the installation is carried out in accordance with the project, and the works are accepted by the commission, which includes a representative of the company who developed the project.
