Flap gate for chimney

The quality of the chimney draft is one of the factors affecting the efficiency of the heating system. It favors the inflow of sufficient air for complete combustion of the fuel and contributes to the timely discharge of gases. Lack of traction provokes the deterioration of all processes and the emergence of reverse thrust when combustion products enter the room. This creates a threat of poisoning and fire. To regulate the processes of exhaust gas through the channel is installed gate valve for the chimney.

Retractable Gate Design

The gate is a metal valve installed to completely or partially overlap the smoke channel. Its installation allows you to change the draft and the intensity of burning fuel. For the manufacture of parts used heat-resistant stainless steel. The thickness of its walls is 0.5–1 mm. In brick chimneys the option of using a cast iron gate valve is possible. It has many advantages: strength, long service life, resistance to chemical attack.

Note! The main disadvantage of the cast iron gate is considerable weight, so the part is not designed for metal pipes.

The gate valve is designed to operate at temperatures up to 900? C. It is installed near the combustion chamber on the first meter of the chimney. This place can not be warmed, so as not to jam the valve. After the termination of the burning process, it is completely closed so that the heat does not go outside.

Specifications

1. The design feature of the part is a low coefficient of expansion and resistance to mechanical stress.
2. The metal surface of the flap is polished to a mirror finish and smoothness. This is necessary to ensure the smooth passage of the products of combustion.
3. In the standard version, the valve covers up to 85% of the chimney channel area. This is the best indicator for the removal of combustion products.
4. The high thermal conductivity of the metal gate does not interfere with the heat exchange system.
5. Stainless steel is characterized by excellent resistance to moisture and acidic compounds.
6. The low expansion coefficient of the damper valve has a positive effect on performance. The part does not require consideration of dimensional changes with temperature fluctuations.

Shiber models

Two chimney flap designs are used:

1. Retractable шибер – распространенная конструкция, представляющая собой горизонтальную пластину, перемещающуюся в специальных пазах. Часть заслонки удалена, чтобы даже при полном закрытии обеспечивалось движение газа и не нарушалась пожарная безопасность. От ее положения зависит размер дымоходного канала. Такую конструкцию несложно изготовить самостоятельно.
2. Turning шибер – заслонка закрепляется на металлическом стержне и вращается вокруг своей оси. Эта конструкция называется дроссельной, она менее надежна и устанавливается, если технически невозможно использовать выдвижную модель. Регулировка пластины выполняется специальной ручкой. Такой тип шибера подходит для газовых котлов, дымоход которых нельзя герметично перекрывать. Для банных печей, протапливающихся только периодически, такая конструкция не подходит, в них устанавливают выдвижную заслонку. С его помощью нельзя частично регулировать изменение сечения дымохода, а можно закрыть или открыть его.

Installing the gate in the brick chimney

1. Laid out the first row of bricks for the chimney.
2. In the side bricks of the second row, grooves are cut through the thickness of the slide gate valve.
3. A through hole is cut in the front brick to accommodate the flap handle.
4. To fix the gate does not require retainers, it is held in place, thanks to a snug fit.

For installation, a finished piece of cast iron or stainless steel is taken. The grooves in the bricks are made by the grinder with a circle for the stone. After installing the damper, you need to inspect the chimney to eliminate the occurrence of cracks. If gaps are detected, they should be covered with a solution of chamotte clay.

Another installation method is suitable for the throttle, it is called a pipe in a pipe. A structure representing a pipe fragment is inserted into a chimney of the appropriate diameter.

Note! The installation has no means of attachment, and the part itself is held due to a snug fit to the channel surface.

We make the rotary gate independently

During operation of the chimney, it may be necessary to replace the gate, and the standard flap is not suitable for this design. In this case, the valve is made independently by the size of the pipe.

The work will require metal shears, a drill, a Bulgarian and a welding machine.

• From steel corners with a shelf size of 35–45 mm, the frame for the flap is welded. The size of the parts corresponds to the diameter of the pipe.
• Holes are drilled in the frame to secure the axle. For a gate with a straight turn, they are located in a horizontal plane, and for a corner gate - diagonally.
• From two pieces of a half-inch pipe, sleeves are welded to ensure the rotation of the axis.
• The valve is cut to the size of the frame, the material is a steel sheet with a thickness of 2-3 mm.
• An axis is inserted into the frame holes on which the damper will be mounted. The second part of the metal part will become a knob for adjustment.
• The plate is inserted into the frame and is fixed on the axis by welding.
• For safe use there should be a gap of 1 mm between the flap and the frame.
• To ensure the fixation of the plate in the open state, set the limiter.

Note! The choice of model of the gate depends on the design of the chimney and the type of heating system, but its installation is required. The device allows you to adjust the level of traction and keep the heating system in working condition.

Video

This video is about how to make a gate valve of rectangular section: