High vacuum fume and dust extraction.
- Erol Köksoy
- Aug 5
- 5 min read
Updated: Sep 12
In engineering and applied physics, vacuum refers to any space in which the pressure is significantly less than atmospheric pressure.
The quality of a partial vacuum refers to how close it is to a perfect vacuum. All else being equal, lower gas pressure means a higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by about 20%.
Vacuum quality is divided into ranges according to the technology required to achieve or measure it.
These ranges are defined in ISO 3529-1:2019 as shown in the table below:
Pressure range | Definition | The rationale for defining ranges is as follows (typical cases): |
100 Pa from the prevailing atmospheric pressure (31 kPa to 110 kPa) | Low vacuum | Pressure can be achieved with simple materials and positive displacement vacuum pumps; viscous flow regime for gases |
<100 Pa to 0.1 Pa | Medium vacuum | Pressure can be achieved with complex materials and positive displacement vacuum pumps; transitional flow regime for gases |
<0.1 Pa to 1 × 10−6 Pa | High vacuum (HV) | Pressure can be achieved with complex materials, elastomer seals, and high vacuum pumps; the molecular flow regime for gases |
<1 × 10 −6 Pa to 1 × 10 −9 Pa | Ultra-high vacuum (UHV) | Pressure can be achieved with elaborate materials, metal seals, special surface preparation and cleaning, baking, and high vacuum pumps; the molecular flow regime for gases |
Below 1 × 10−9 Pa | Ultra-high vacuum (XHV) | Pressure can be achieved with complex materials, metal seals, special surface preparation and cleaning, baking, and additional degassing pumps; molecular flow regime for gases |
Suction is the everyday term for the forces experienced by objects subjected to the motion of gases or liquids moving along a pressure gradient. However, contrary to popular belief, the forces acting in this case are not caused by the low pressure side (vacuum), but by the high pressure side.
When the pressure in one part of a physical system is reduced relative to another, the liquid or gas in the higher-pressure region will exert a force, called a pressure gradient force, relative to the lower-pressure region. If all the gas or liquid were removed, the result would be a perfect vacuum where the pressure is zero. Therefore, negative pressure forces cannot be generated. Therefore, from a physics perspective, objects are repelled, not sucked.
The pressure reduction can be static, as in the piston and cylinder arrangement, or dynamic, as in the case of a vacuum cleaner, where the air flow reduces the pressure zone.
When living beings breathe, the diaphragm and muscles surrounding the rib cage cause volume changes in the lungs. The increased volume of the thoracic cavity reduces the pressure inside, creating an imbalance with ambient air pressure, which causes suction. Similarly, when a liquid is drawn into the mouth using a straw, atmospheric pressure pushes the liquid through the straw along the pressure gradient.
In spacecraft or aircraft accidents, when objects are ejected during an uncontrolled decompression, a common mistake is to incorrectly refer to them as being sucked out. This is not sucking in, but pushing out.
The performance of a high vacuum suction unit can be measured by several parameters:
Air flow, in liters per second [l/s] or cubic feet per minute (CFM or ft3/min)
Air speed in meters per second [m/s] or miles per hour [mph]
Suction, vacuum, or water lift, in pascals [Pa] or inches of water
Air Intake (Pa):
Suction is the maximum pressure difference a pump can create. For example, a typical household vacuum cleaner has a suction rating of approximately negative 20 kPa. This means it can reduce the pressure inside the hose by 20 kPa from normal atmospheric pressure (approximately 100 kPa). The higher the suction rating, the more powerful the cleaner. One inch of water equals approximately 249 Pa; therefore, the typical suction is 80 inches (2,000 mm) of water.
Input power (W):
A unit's power consumption in watts is usually the only figure quoted. Some manufacturers only quote current in amperes (e.g., "6 amps"), and the consumer must multiply this by the mains voltage to obtain an approximate power rating in watts. (Watts = Voltage x Amps)
Rated input power only indicates how much electricity the unit consumes, not its efficiency.
After August 2014, due to EU rules, the production of vacuum cleaners with a power consumption of more than 1600 watts was banned within the EU, and from 2017 onwards the production of vacuum cleaners with a wattage of more than 900 watts was not allowed.
Output power (AW):
The amount of input power converted into airflow at the end of the suction hose is sometimes stated and measured in airwatts . The unit of measurement is simply watts. The word "air" is used to clarify that this refers to the output power, not the input electrical power.
The airwatt is derived from English units. ASTM International defines the airwatt as 0.117354 × F × S, where F is the airflow rate in ft3/min and S is the water pressure in inches.
Maximum horsepower:
A unit's peak horsepower is usually measured by removing the cooling fans and calculating the power based on the motor power plus the rotational inertia energy stored in the motor armature and centrifugal blower. The peak horsepower rating is often an impractical figure and is only valid for very short periods of time. Continuous power is usually much lower.
Air flow rate:
Typical units for expressing air flow rate are:
By volume
m 3 /min (cubic meters per minute )
m 3 /h (cubic meters per hour)
ft 3 /h (cubic feet per hour)
ft 3 /min (cubic feet per minute, also known as CFM)
l/s (liters per second)
Massively
kg/s (kilograms per second)
Airflow can also be described in terms of air changes per hour (ACH), which indicates the exact volume of air replacing that fills the space in question.
The simplest formula for volumetric air flow is Q=VA. Q=flow rate, V=air velocity, A=cross-sectional area through which the air passes.
For mass air flow rate, the formula m=pva is used. m= mass flow rate (kg/s), p= density (kg/m³), v= velocity (m/s), a= cross-sectional area (m²)
High vacuum suction units are used in many areas of industry.
The main parts that attract our particular attention are:
High vacuum fume extraction from manual welding torch
High vacuum fume extraction from automation welding torch
High vacuum fume extraction from robotic welding torch
High vacuum dust extraction from grinding machines
High vacuum dust and chip extraction from machining centers
High vacuum suction from the source of cutting dust
High vacuum suction from the source of stone/marble dust
High vacuum suction from the source of machining burrs
Industrial cleaning operations
We manufacture and import custom high vacuum units for the needs listed above and more.
We also supply the necessary auxiliary equipment for dust and smoke extraction.
These can be extraction equipment mounted on torches, dust extraction caps for angle grinders and more.
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