The movement of air flows in the smoke exhaust channels is subject to the laws of physics, however, with the help of some devices you can adjust the traction. One of these devices is a slide gate - an indispensable attribute of a home or bath stove.
We will find out what types of valves there are and whether it is possible to build a gate for the chimney with your own hands, if there is no factory analogue at hand. The chimney element has a very simple design, but its manufacture requires at least minimal metal processing skills.
What is a slide gate
The German word Schieber in Russian did not change either pronunciation or meaning. Speaking specifically about stove heating, a shutter type, which closes the chimney channel, is called a gate, as well as a gate valve.
When arranging a chimney, the valve is installed in the upper part of the base, which is located in the room, so that, if necessary, it was possible to manually control the movement of gases, and at the same time the quality of the draft.
This is how the gate looks in the extended form. In the retracted state (when the furnace is already melted), the valve is almost invisible, only its "ear" protrudes outward
A chimney damper is required with a traditional brick oven. By pushing it partially or completely, it is possible to reduce draft or block the movement of heated gases.
The damper is completely closed when the furnace is flooded and harmful gases cease to flow into the channel. Cases of death of people who have burned out of an early “closed” furnace are known.
If you are late in closing the damper, the heat from the heated bricks will go into the pipe, and the room temperature will quickly drop. A timely shutter is a guarantee that the house will be warm for at least a day. As you know, in village houses in the cold season you have to flood the stove every morning.
Steel gate valve factory production with a diameter of 200 mm. To simplify installation, it is sold with a steel pipe
There is an opinion that the dampers, mandatory for brick furnaces, are absolutely not necessary for the installation of steel furnaces (although they are offered by manufacturers), as well as for models with a deflector installed.
An argument against their use is the fact that the chimney with a closed valve is quickly clogged with soot. Its upper part is cooled from the cold air entering the pipe, which when in contact with a hot steel pipe forms a large amount of condensate. This situation requires more frequent cleaning of the chimney.
Differences between retractable and rotary gate
So far we have been talking about the sliding form of the slide gate on the stove chimney, although there is another type - rotary. Consider how they differ.
The purpose of both varieties is the same - to partially or completely block the flow of flue / heated gases. Differences relate to design.
A retractable model is a metal plate that is fixed in a frame and moves along the rails in a horizontal position. There are no strict requirements for the dimensions of the device, since they must correspond to the cross section of the chimney and are completely dependent on its parameters.
Thus, the valve consists of two main parts:
- frames, which is fixed in the chimney and is stationary;
- platesmoving inside the frame.
As a rule, both parts are made of the same material in order to maintain performance when heated or cooled.
A properly designed and installed damper should never completely block the stove chimney. Small clearance required for fire safety
The design of the rotary (throttle) gate does not extend, but rotates along the axis, as the name implies.
A round or rectangular plate (depending on the cross section of the chimney) is fixed on a metal rod, the free end of which extends beyond the channel and is an adjustment tool.
The simplest model of a rotary gate with a diameter of 120 mm. Production material - stainless steel. The chimney canal is overlapped by turning the handle with a bent end
Gate valves are considered more reliable and wear-resistant devices. The weak point of the rotary devices is the connection of the rod and plate, which over time loosens and renders the damper unusable.
What material is stronger
In addition to structural differences, the types of gates can differ in the material of manufacture. The only possible option is metal, since only it does not burn and does not deform at high temperatures, and does not change its characteristics over time even in an aggressive environment.
For production use either cast iron or stainless steel. It is not possible to independently construct a shutter of cast iron, since this requires at least a forge. However, on sale you can find both plain and beautifully designed cast-iron dampers.
Cast iron rotary gate with a convenient handle. This design is suitable for a brick chimney with a rectangular cross-section, capable of withstanding the rather heavy weight of the device
Steel products look simpler, but their characteristics are similar to cast iron counterparts. The advantage of steel fixtures in light weight.
If the cast-iron gate valve for the furnace chimney is installed only on a solid, solid structure, the steel valve is suitable for any chimney ducts - brick and steel, rectangular and round, solid and light.
Samples of a galvanized steel gate valve, the diameter of the cross section of the chimney is 150 mm. Galvanization, unlike ordinary steel, does not respond to moisture (condensate) and is not susceptible to corrosion
When choosing a material, it is necessary to focus on the characteristics of the chimney pipe and the features of the interior.
A modest steel gate valve is enough for a heating cottage stove, while a custom-made cast-iron gate is better for ennobles the Russian stove in a cottage.
How to make a gate valve yourself
Consider how to make both versions of the valves for chimneys - retractable and rotary. Each of them has its own nuances of manufacturing and installation. Let's start with a retractable view.
Preparation of materials and tools
To create the simplest model of retractable gate, galvanized steel is suitable. It is lightweight, due to its smooth surface it is easily cleaned of soot, and if necessary, the moving part can be easily replaced.
Millimeter steel will not work, since it easily bends, and during deformation there will be difficulties with the plate being pushed into the chimney. The minimum sheet thickness is 1.5 mm, and preferably 2-2.5 mm
The main tools are a welding machine, electrodes, a grinder, scissors for metal (choose depending on the thickness of the sheet), a drill with a grinding disc, drill bits for metal, a file.
Work is best done on a work bench with a vise. Among other things, you will need a sheet of paper for the template, tape measure, marker.
Drawing up the scheme (drawing)
Dimensioning needs to be taken seriously, since even a few millimeters can cause the chimney to malfunction. To find out the dimensions of the frame, measure the cross section of the chimney duct with a tape measure - it will coincide with the dimensions of the inside of the frame.
To this value should be added 20-30 mm from three sides and calculate the outer side of the frame.
Drawing of a shutter with a wire frame. A wire frame is more difficult to fix on brickwork than a profile with flat wide sides
For the valve to extend easily, without effort, it should be slightly narrower than the width of the frame (if you take into account the external sides). To simplify the calculations, it is necessary to draw a design diagram and designate all possible sizes so that in the future, while working with metal, you can navigate along them.
For metal pipes, the design of a flat damper is usually combined with a chimney fragment located perpendicularly.
Dimensions of the construction for a rectangular pipe. The valve must completely block the chimney, but at the same time have small holes for air penetration, drilled by a drill, or a gap
For brick chimneys, a sufficiently flat frame of wire or profile with a moving valve on the guides on two parallel sides is sufficient.
Marking and cutting parts
Having determined the exact dimensions, we cut out the frame for the gate. If the chimney is small, for example, in a bathhouse or in a summer kitchen, you can use a thick wire by bending it in the form of the letter P.
A more detailed frame is a robust corner profile. To make it, we cut a strip from sheet steel and bend it lengthwise at an angle of 90º. To give the profile the desired shape, in places where the angles are outlined, we cut one of the planes. When bent, we get a frame. We weld the bending places.
Next, cut out the damper itself. It should be about 5-10 mm narrower than the width of the frame. We adjust the length so that in a closed state only a small fragment of the valve looks out. It can be decorated in different ways: in the form of an eye with a hole or just a bent edge.
The edges of the cut-out gate are cleaned with a disk so that the closing / opening process takes place easily and silently. It is impossible to paint details.
Valve installation steps
The photo shows the steps of installing a factory-made gate. By the same principle, a home-made device is mounted.
Image Gallery
Photo from
Step 1 - determining the installation location
Step 2 - cutting bricks around the perimeter of the hole
Step 3 - landing the gate on the solution
Step 4 - masonry over the gate
The installation height of the damper largely depends on the design of the furnace, it is lower in bath furnaces, and higher in heating for homes. The minimum height is 0.9-1 m from the floor, the maximum is about 2 m.
Rotary Gate Instructions
Consider the option of manufacturing a slide gate valve for a metal pipe. Such a modification can be mounted both in a new chimney and in a ready-made and functioning stove.
It is a circular plane with a welded metal rod - a kind of rotary mechanism and holder in one person.
Production material - a sheet of stainless steel 2-2.5 mm thick; metal rod 6-7 mm (hollow tube); a pair of 8 mm bolts, a piece of metal fittings or a nail.
To cut and weld parts, you will need:
- a grinder with a set of discs - abrasive and detachable;
- marking tool - marker, construction tape, compasses;
- welding tool - welding machine, electrodes for steel, core;
- vise, pliers, wire cutters, hammer.
Also, during welding, protective clothing is required - gloves, glasses, overalls made of thick dense fabric.
Working process:
Image Gallery
Photo from
Before marking, it is necessary to measure the diameter of the pipe, and then use the compass to transfer the dimensions to a stainless steel sheet
Cut the shutter with a drill with a cutting wheel. We try to cut exactly so that the edge is neat
We take the cut out steel circle and insert it into the pipe. If the sizes do not match, we finish the edges by grinding
To cut the tube to the desired size, apply it to the finished damper. The tube should be shorter than the diameter of the circle, 0.3 cm from each end. Then cut by marks
To make the internal thread on the tube, the edges must be drilled to a size of 6.8 mm. In the process, lubricate the surface of the tube with machine oil
For threading, we use a special tool - a tap, which also needs to be lubricated with machine oil. We remove the chips by reverse rotational half turns of the tap
In a straight line through the center of the circle we put marks with a marker, then we drill three holes - one in the center and two at the edges. Through the holes we weld the tube
In two pre-prepared holes, we insert bolts on both sides, which are screwed into the slide tube inside the pipe
Stage 1 - marking on a steel sheet
Stage 2 - cutting a steel circle
Stage 4 - trimming a metal tube
Step 5 - Drilling a Thread Tube
Stage 6 - threading
Stage 7 - cutting holes for welding
Stage 8 - installation of the gate in the pipe
It remains to make a latch for the handle of steel sheet. The finished gate must be cleaned of soot from time to time, and it is also necessary to control the strength of the weld points.
With the help of videos you will expand your horizons, learn more about stove valves and how to install them in the chimney.
How to make a shutter in 5 hours:
Scheme of mounting the gate on a brick furnace:
Option for installing a choke for the fireplace:
It is advisable to engage in self-production of a gate if you have metal working skills, are able to use welding, a grinder and a drill - then the production process will benefit and positive emotions.
If knowledge and skills are not enough, it is better to purchase a ready-made valve, having previously taken the dimensions from the chimney.
There is something to supplement or have questions about the topic - you can leave comments on the publication. The contact form is located in the lower block. If you yourself made a gate for the chimney and want to share ideas with readers - please add a photo of the product.