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options for capturing wood dust.

by:Gewinn     2020-02-26
Here are some ideas for improving dust removal efficiency based on several manufacturing variables.
The design of a reasonable dust removal system can bring many benefits.
Reduce maintenance and heating costs, reduce fire risk, and cleaner ground and machines.
More importantly, employees will be healthier and happier, which will help improve productivity.
Typical dust removal systems include covers (s)
Dust Collector (s), fan(s)and ductwork.
The following article defines the basic components of the dust removal system and outlines the advantages and disadvantages of various dust collector options.
Good Hood is essential for most machines and operations, effective control of wood dust starts with proper collection at the source.
The hood is used to generate air flow and deliver wood dust from the source to the dust collecting system.
The hood must have the appropriate size and position to ensure that there is enough airflow to enter the Hood to control the dust.
The airflow must be high enough to capture wood dust and overcome the airflow caused by machine movement and indoor airflow.
To make the system economical, the Hood should be as close to the dust source as possible.
The airflow required to move wood dust from a particular machine or operation depends on the size of the machine, the amount of dust generated, and the method of generating dust.
Industrial sanitary engineers, equipment manufacturers or engineers proficient in dust control can help determine the airflow required for the machine.
The hood is attached to a pipe that transports wood dust to the collection point.
Typically, the design airflow speed of the pipe is 3,500 to 4,500 feet per minute.
The lower speed is not enough to deliver wood dust through the pipeline and may result in unsafe accumulation of dust within the pipeline.
Higher speeds can lead to excessive pressure drop in the pipeline, resulting in higher operating costs.
They also increase the wear and tear of the pipes.
The fan generates the required airflow to deliver the captured wood dust through the system pipe.
Select the fan according to the airflow, static pressure and noise requirements required by the system.
Several types of vacuum cleaners are suitable for capturing wood dust.
The oldest and simplest dust collector is the Cyclone dust collector.
The rotation of the air flow in the cyclone results in centrifugal separation of heavier dust particles.
Cyclone is less efficient in very thin, low places
Density particles.
These are the most dangerous particles because they are still in the air and are easily sucked into the lungs.
Due to its low efficiency for free wood particles, the cyclone is usually used for places where air does not circulate into buildings, or as a pre-cleaner for more efficient dust collectors.
Other dust collectors are usually described using the filter type and cleaning method used.
A small application that is still designed for 500 cubic feet per minute (cfm)to 8,000 cfm -has envelope-style bags.
Although other woven materials can be used, these bags are usually woven with cotton.
The envelope was dusty outside.
The envelope collector is the most inefficient in fabric filters because of the aperture generated by the weaving process.
The felt bag filter is commonly used as a filter for the bag filter.
Due to the small fiber size, tight fiber packaging and large media thickness, these filter bags are more efficient than fabric envelope filters.
The initial efficiency of the envelope or bag filter is usually too low, and air recycling is not allowed until the filter is seasoned.
When wood dust gathers on the surface of the filter, it forms a dust cake that increases the efficiency of the filter.
During the hours or days of operation, the combined efficiency of the filter cake and filter is sufficient to allow recycling.
The latest and most effective filtration technology in many wood dust collection applications uses a filter cartridge.
The cartridges are usually cylindrical, using pleated cellulose or synthetic materials as filter media and allowing immediate air recycling of new cartridges.
In addition, the pleat design provides the cartridge with much more filter media than the same medium
Envelope or bag size.
The increased surface area means that the size of the wood dust removal system using the filter cartridge can be smaller.
As the thickness and density of the dust cake increases, the limit on airflow from the cleaning collector with envelopes, bags or cartridges will also increase.
If the media is not cleaned, the airflow will be reduced to a point where the hood cannot effectively control the dust near the device.
Cleaning is usually done by shaking or pneumatic cleaning.
Because the airflow must be stopped in order to shake effectively, the shaking device is used on smaller devices that do not require continuous work.
The shaker unit can be manually cleaned or electrically cleaned by lever or crank.
Most of the larger wood dust collection systems use some form of pneumatic cleaning.
Cleaning is done by forcing the air to flow backwards through the cartridge bag, which blows wood dust out of the filter and into the collection hopper or dust drawer.
This type of cleaning is feasible because cleaning can be done when the dust collector is running. Medium-
Pressure pneumatic cleaning is commonly used in large bag dust collectors with heavy dust load.
The rotating arm of the air side of the air bag chamber is used as a blow pipe, explosive medium-pressure air -
10 pounds per square inchpsi)to 15 psi -
Enter a small part of the filter bag at a time.
When these bags are cleaned, the remaining bags remain in normal operation.
Use a pressure blower to generate clean air and therefore do not require expensive compressed air from a store or factory. High-
Pneumatic or pulse pressure-
Some bag dust collectors also use get cleaning.
Using this cleaning method, multiple diaphragm valves use compressed air from 90 to 100 psi to clean a portion of the filter bag at a time.
Like the media.
Pressure cleaning, only pulse part of the bag at a time, so cleaning will be carried out during continuous operation. High-
Pneumatic or pulse pressure-
Jet bags are usually used for light to medium dust loading.
High-use
Compared to bag rooms using media, pressure cleaning allows these bag rooms to operate under increased airflow
Pressure cleaning.
This means that smaller dust collectors can be used, thus saving valuable floor space and initial capital costs.
Whether it is baghouse style, the convenience of maintenance is a concern.
Filter bags need to be replaced regularly-
Normal operation every two to three years.
Prefer the design of bag ethics that allows clean air side, because in safe, clean area, replacement is faster.
Unloading bags from the dirty side of the bag filter is usually cumbersome and requires maintenance personnel to pay special attention to safety.
This is an important consideration for large bag houses that may have 500 or more filter bags. Cartridge-
In recent years, the style wood dust collector using fold media has been successfully applied to a variety of wood dust applications.
These cartridges have high efficiency in service life.
The proper cartridge design must take into account the special properties of wood dust, which is usually fiber compared to other manufacturing dust.
Special designs are provided to ensure maximum release of fiber wood particles during cleaning operations.
The cartridge collector using shaking as a cleaning mechanism can be used for relatively low airflow-
500 to 3,000 cfm.
These systems, such as the other vibration devices discussed, are cleaned when the fan is turned off. Pulse-
High usage of cleaning cartridge collector
Clean the pressure air jet of the cartridge.
Cleaning can be done when the system is running.
There is an air inlet at the top, and the filter cartridge dust collector with the airflow going down through the element is particularly effective when cleaning, because the downward airflow helps the gravity to remove dust during the cleaning pulse.
This design minimizes duplication
Pulse dust is carried back into the cartridge.
In terms of the initial capital cost, the filter cartridge dust collector can be comparable to the air bag dust collector.
However, the reduction in system size, the ability to circulate air at any time, and the simplified maintenance of the cartridge make the cartridge dust collector an option for several woodworking applications compared to the bag.
For some operations, such as hand polishing, the source capture of the wood is not easy to complete.
This may be due to the size of the workpiece or the need to manipulate the workpiece to reach all surfaces.
This dust is still a serious trouble because it is usually small in size and still in the air.
Such operations can easily produce dust that exceeds the statutory limits, forcing operators to wear uncomfortable masks.
This wood dust can also endanger the quality of other processing processes, such as finishing.
The environmental control booth is an answer for hand polishing.
These collectors create an airflow pattern that draws wood dust from the operator into a set of filters, usually high-
High efficiency pleated cartridges.
These booths are equipped with integral fans, pulse cleaning, lighting and sound insulation walls to provide the operator with comfortable and safe working conditions.
The size and airflow of the booth can accommodate a variety-
Workpiece size and operation.
Suitable dust collectors for specific applications depend on many factors.
Engineers with dust removal technical qualifications can design a system that can provide the benefits of cleaner, safer and more efficient operations.
Related articles: When choosing pipes, fittings and hoses for woodworking dust removal, there are several things to consider when choosing the right pipes and hoses.
Pipes and fittings shall be constructed of galvanized metal.
Static electricity is generated if plastic materials are used.
On the other hand, the price of stainless steel is extremely expensive, and the black iron pipe will rust soon. Air-
Tight seams must be used in order to avoid leakage.
Sealing of on-site joints is critical.
In order to avoid pipe collapse, proper gauges and structures must be used.
The outer ribs of the spiral pipe provide a huge support for the collapse under the vacuum.
The furnace tube is designed for positive pressure systems, not vacuum systems (
Negative pressure).
All hoses for dust removal should have wire reinforcement.
This provides the hose with the strength required to withstand the vacuum.
There are four kinds of materials recommended for use in flexhose for dust removal: rubber, polyester neoprene, metal and polyurethane.
The rubber is affordable and durable and can be used for most general purpose hoses.
Polyester neoprene coated hoses are the most unlikely to generate static electricity, thus benefiting Sanders.
Polyester neoprene is a flame retardant general purpose hose but not good for outdoor use.
Metal hoses are very durable and cost-effective
Effective, but creates greater resistance to flow.
Finally, polyurethane, while expensive, is one of the best materials for making hoses, as it has the best wear resistance, tear strength and puncture resistance.
Polyurethane is widely used in die press, reel machine, planing machine and CNC router.
PVC hose is not good for dust collection.
PVC is used to transport smoke and it is not recommended to collect dust due to the accumulation of static electricity.
Choosing incorrect pipes, fittings and hoses will be detrimental to the performance of the dust removal system.
Editor\'s note: The information in this article is provided by the air handling system of CT Woodbridge.
For more information, please contact Curt Corum, sales manager (800)367-3828.
Faith Salchert is the product manager of Donaldson\'s Torit products.
In Minneapolis, United States of America
Can be in (612)887-3930.
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