Work associated with the formation of dust, the emission of toxic gases, fumes, require the arrangement of a workplace and premises with an exhaust system. In most cases, do-it-yourself ventilation in the workshop is the most affordable way to solve the problem.
There are various options for constructing air exchange systems. We will help you navigate in their diversity, consider the features of building ventilation for each type of workshop. We will analyze the most effective and affordable options for self-installation.
Types of ventilation systems in the workshop
According to the method of air circulation in the room, two main types of ventilation are distinguished:
- natural;
- forced.
In the first case, the movement of air occurs due to the temperature difference indoors and outdoors.
And in the second circulation is provided by fans, creating in the workshop overpressure or vacuum. Such ventilation is also called mechanical ventilation.
Quick removal of contaminated air from the workshop is not possible without mechanical ventilation. But this does not mean that in such rooms a natural range hood is not used, they often complement each other
In turn, forced is of the following types:
- exhaust;
- supply;
- combined.
Exhaust ventilation ensures the removal of harmful gases, vapors, while clean air enters the workshop naturally. Supply, on the contrary, creates excessive pressure inside the room due to the intake of street air, and the exhaust is squeezed out of the workshop out through natural openings, cracks. If necessary, the input stream can be heated, cleaned, or moistened.
Combined workshop ventilation system called supply and exhaust. Depending on the relative position of the air supply and exhaust channels, circulation can occur by displacement or mixing.
If the supply fans are at the bottom, then the rising cold air displaces the warmer. With the upper location of the inlet channel, the cold stream is distributed throughout the room, sinking down, mixed with warmer. Then the exhaust air is removed by an exhaust duct.
Depending on the organization method, ventilation in the workshop is divided into two types:
- local
- centralized.
The first is used to remove harmful substances directly from the workplace. It is advantageous to use it to localize pollution when units of equipment are removed from each other throughout the entire area of the room.
Proper organization of the suction system eliminates explosive wood dust, preserves the health of workers. The centralized system is used for high intensity and continuous work in the workshop.
For small workshops with a more compact arrangement of machines, it is advisable to install a centralized hood.
Also apply hybrid ventilation optionswhen part of the machines is connected to a common system, and part has local filtering. In some cases, they mainly prefer local systems only, to prevent the dispersal of fine dust and other toxic substances throughout the workshop.
Features of the arrangement of ventilation in the workshop
Work in the workshop is associated with the presence of toxic and unhealthy substances in the air.The design and construction of ventilation in such rooms depends on the type of work and the nature of the harmful factors.
Consider the main features that affect the configuration and parameters of ventilation systems for different types of workshops.
#1. Dust removal in a carpentry workshop
Fine dust is the main problem of woodworking workshops. Such a suspension of particles can be in the air for 24 hours, although it is not noticeable to the eyes, but is inhaled by the lungs. In addition, it settles on all surfaces. With any draft or engine start of machines, tools, it again appears in the air.
The organization of a dust removal system (aspiration) is complicated by the presence of a large number of dust sources and various fractions of chips. For this reason, suction hoses with individual filtration must be connected to each machine.
Dust extraction systems operate on the principle of cyclone. The polluted air is drawn in by the rotational movement of the fan and, under the action of centrifugal force, heavier dust particles sink to the bottom of the tank. Purified air rises. Additionally, wetting of the flow may occur for better cleaning.
But, in addition to harmful effects on breathing, wood dust still has fire and explosive properties. Which makes increased demands on ventilation systems in terms of eliminating electrostatics and grounding structures.
# 2 Car air cleaning
Car service workshop refers to rooms with high air pollution. The constant presence of exhaust gases, carbon monoxide and nitrogen, aerosols, gasoline vapors, paints and other technical fluids places special demands on the performance of the ventilation system. The power of the supply and exhaust unit is selected with a margin to ensure the pumping of the entire volume of the room with a recommended multiplicity of 20 - 30.
In addition, contaminated air must be filtered and discharged separately from the general ventilation pipe.
# 3 Ventilation of repair and blacksmith workshops
The products of electrode burning, smoke, cinder and dust released during welding and locksmithing work during cutting and metal processing require removal using local hoods. What is regulated by STO 221 NOSTROY 2.10.64-2013
For manual electric welding, their approximate productivity is selected based on the provision of air exchange from 1500 to 4500 thousand m3* h / kg divided by the weight of electrodes burned in 1 hour.
In semi-automatic welding, the volume is increased to 1700 - 2000 thousand m3* h / kg.
Equipment ventilation of the welder's workplace is of paramount importance. Vapors of metals and slag contain harmful oxides of manganese, compounds of silicon, titanium and other chemical elements that lead to diseases of the nervous system, lungs, are able to accumulate in the body
The general air circulation is distributed in the ratio of inflow to exhaust hood 1: 3 for the upper tier, and 2: 3 for the lower tier.
A ventilation feature of the forge workshop is the need to remove excess heat and toxic gases. To do this, use local suction above the furnaces and natural ventilation.
When calculating the performance of ventilation systems for all types of workshops at the recommended multiplicity, it is necessary to take into account heat loss in the cold season. The choice of maximum parameters will guarantee the rapid removal of harmful substances, but at the same time, it will require the cost of heating the supply air. If heat recovery is not provided, it is better to stop the choice at the lower permissible multiplicity limits.
Workshop ventilation options
In the search for the best ways to build ventilation for your own workshop, you have to review many possible options before you find the most suitable.
To facilitate this search, we will consider, as an example, the most successful, in our opinion, solutions for independent arrangement of ventilation in the workshop.
Option # 1 - exhaust ventilation from plastic pipes
For the implementation of this project the following were used: the used “snail” centrifugal fan with an electric motor of 2, 2 kW, a barrel of 40–50 liters with a mouth corresponding to the “snail” inlet, and sewer plastic pipes of 110 mm.
A centrifugal fan, in contrast to an axial fan, creates more pressure. This allows you to build on its basis more extended and extensive ventilation systems in the workshop
A few words about the material of the ducts. The use of plastic sewer pipes for ventilation is a fairly popular option, primarily due to the price. They are several times cheaper than plastic and steel ducts for ventilation.
But sewer pipes have their drawbacks:
- they can not be used in places where the temperature can exceed +60 degrees;
- they do not have an antistatic coating, so it is not advisable to use them for chip and dust removal systems;
- their diameters do not meet the standards of ventilation systems, which makes it difficult to pair with other equipment.
Despite these shortcomings, in most cases, sewer pipes are successfully used as ducts. The considered option of the device ventilation system from improvised materials was no exception.
In this project, all the main components of the hood for a locksmith workshop were made by hand. Let us briefly describe the stages of the work done.
So, at first, overhaul and refinement of the centrifugal fan was carried out. The refinement concerned the inlet pipe. More precisely, because of its absence, it was necessary to produce a new one from a small sealed barrel, the volume of which would allow the fan to pick up the necessary speed of the vortex flow.
A side hole was made in the barrel and a piece of plastic pipe was glued, taking into account aerodynamics, so that the input stream went along the inner circumference of the barrel. Then, an air duct made of plastic pipes was mounted under the ceiling in the center along the entire workshop.
The barrel in this project acts as a receiver, which was created with the prospect of expanding the ventilation system by incorporating several inlet pipes
The centrifugal fan creates a powerful vortex flow in the barrel, which ensures fast air circulation throughout the system. Its strength is so great that it keeps the saw blade of the grinder on the most distant air inlet.
The exhaust system parameters are as follows:
- engine power 2, 2 kW;
- fan speed 2800 rpm;
- productivity 1000 m3/ h - 1500 m3/ h;
- the time for extracting the entire volume of air from the workshop is 5 to 10 minutes.
The whole system has 6 air inlets closed with homemade adjustable plugs. They are made of regular plastic with cut-out slots in the lid, and the same slots in a movable metal plate fixed on one axis. With their mutual rotation, the air flow is regulated.
Option # 2 - a dust collector from the KAMAZ filter
Since factory dust extraction systems are quite expensive, homemade dust collectors based on air filters from large KamAZ trucks, tractors or combines are widely used.
Having supplemented such a filter with a fan, they get a good air purifier, which takes up a minimum of space and is easily transferred to any part of the workshop.
The performance of such a system is regulated by the selection of fan power. Such filters can clean the air volume from 500 to 1000 m3 per hour, depending on type. You can connect fans to them with a productivity up to 300 - 400 m3/ h
The dust collector can be suspended from the ceiling. The mount should allow periodic removal of equipment and clean it. This is best done with compressed air on the street.
Assembling an air purifier is quite simple. To do this, cut the flange, fix the pin on the axis to the length of the filter. Next, glue the fan to the flange and screw the entire structure to the filter.
Due to the simplicity of manufacture and low cost, such filters can be made several and significantly improve the air throughout the workshop.
Option # 3 - aspiration system in a carpentry workshop
The main role in the proposed dust removal system is played by the JET factory chip cleaner. The cost of such equipment, depending on the parameters, is 15 - 40 thousand rubles. Most models have a dust bag and a chip bag.
For this option, the best model JET DC-1200CK was selected with a paper filter element in the form of a removable drum. It is equipped with a manual device for internal cleaning, which allows you to remove the main dust without removing the filter.
Ventilation pipes were selected to provide maximum protection against electrostatics and the lowest resistance to air flow. In the best way, twisted galvanized steel pipes meet these requirements.
During their installation with a multimeter, the reliability of electrical contact at the connection nodes was checked. If necessary, the contact was strengthened by two screws on opposite sides. The entire pipeline was grounded. In addition, the joints were wrapped with aluminum tape for tightness.
Work in the workshop is organized in such a way that all workbenches and machines can be moved on wheels to the center of the room and connected to the exhaust corrugation as they are used. Thanks to this, the workshop maintains almost perfect cleanliness and lack of dust.
To reduce noise and dust, the exhaust system is moved outside the workshop to the adjacent room of the boiler room. The supply pipe is laid through a hole in the wall under the ceiling. The inlet pipe is fixed to the ceiling in the middle of the workshop. He is wearing a corrugated two-meter pipe made of transparent plastic.
In addition to aspiration, air exchange in the carpentry workshop is provided by supply and exhaust ventilation.
One of the options for hoods in the workshop:
Where is the best place for a chip pump? More on this in the next video:
Option to equip a mobile hood for the workshop:
The options discussed above do not cover the entire set of methods for independently constructing ventilation in the workshop. But, at least, they will help you choose the right direction of your own project and avoid a long trial and error path. Practice shows that a ventilation system of sufficient performance for the workshop can be completely designed and installed with your own hands.
Do you have questions about the ventilation device in the workshop? Or want to tell other users about how you organized an effective air exchange and dust removal system on your own, using improvised materials? Share your experience, ask questions to our experts - the comment block is located below this publication.