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Pneumatic Conveying SystemsGeneral

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From a technical point of view, pneumatic conveying is based on the transport of solid particles missed with a gas, usually air. By mean o pneumatic conveying solid particles of varying sizes can be transported between points, for example from a store to a process machine. Pneumatic Conveying depends on a access to compressed air or a source of vacuum, a feed device where air is mixed with the solid particles, a conveying pipeline and a receiving device which separates the carrier air from the particles.

Pneumatic conveying systems are divided into three categories:A. Positive-pressure systems, where the material is blown through the conveying pipeline by compressed air. B. Negative-pressure systems where the material is sucked through the conveying pipeline.

C. Fluidized beds. The force of gravity is utilized in combination with fluidization. The fluidizing layer of air lowers the friction and makes the material run like a liquid.

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Positive-pressure conveying systemsThe advantage of positive-pressure system is that bulk material can be distributed from one source to several locations through a system of valves.


Usually positive-pressure systems are divided into lowpressure and high-pressure systems. A high-pressure system has much greater capacity as regards the quantity of material which can be conveyed and also allows significantly longer conveying distances than are possible with low-pressure systems.

Positive low-pressure system, Pressure about 1bar

In low-pressure systems (pressure 1bar) bulk material is usually fed in with the help of a rotary valve or screw. The low-pressure system provides a continuous flow. In the receiving container, the carrier air is filtered out through a filter cartridge.

Positive high-pressure systems(7~8bar) can provide much higher material flows (>150ton/h) over much longer conveying distances (>2km). In order to avoid leakage through the feed device, the material is put into a blower thank. The valve between the storage silo and the blower thank is closed and compressed air blows out the material. The thank is refilled and the procedure repeated. The carrier air is filtered in the receiving silo.

Positive high-pressure system, pressure 7-8bar

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Vacuum Conveying SystemsWith vacuum systems, material can be sucked from several pick-up points and collected at one receiving point. This is the opposite of what happens in positivepressure systems. Vacuum systems have lower material flows than positive-pressure systems. Maximum conveying distances may, for favorable materials, be 100-150m. The limitation of the conveying capacity is due to the fact that vacuum systems only utilize atmospheric pressure, while in positive-pressure systems considerably higher pressure can be achieved.


Fluidized bedsIn fluidized beds the air passes through a porous filter material. The passage of air lowers the friction and gravity causes the material to run like a liquid. Very high material flows can be achieved bout the material must have specific properties which allow fluidization. A angel slope of one or two degrees is required to set the material in motion.

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Advantages-Disadvantages with different pneumatic conveying systemsConveying System Positive high pressure system Long distance conveying High capacities Advantages Disadvantage Risks of leakage Heavy installations Expensive components Wear on material and system


Positive low pressure system Less wear on material and system Continuous flow Vacuum Conveying system No leakage of material Simple to install Dustless Easy to control Fluidized beds Angle of transport from only 2-3 slope No moving parts Dusty conveying Open system Limited conveying length Limited capacity Usually intermittent operation Limited conveying length Risks of leakage Feeder often needed

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The Principles of Vacuum conveyingIn the field vacuum conveying technology we speak of vacuum conveyors being used for sucking material. What actually happens is that the air is evacuated from the suction pipe and the pressure from the atmosphere pushes the material into the suction pipeline. It is the atmospheric pressure that performs the work indirectly. The stream of air which is formed on pressure equalization pulls the solid particles into the pipeline. Transport direction


PATM

P-

All Vacuum conveyors works on the same main principle, as illustrated below. The material is conveyed from a suction point through a pipeline to a container, where the air and the material are separated. The filter cleans the air before it passes through the vacuum source. A control unit regulates the operating sequence.

Block sketch Vacuum conveying

Control equipment

Direction of product flow

Container

Filter

Vacuum Pump

Pipeline

Suction Point

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Material flowThe material flow is determined by the diameter of the conveying pipeline, the vacuum flow the conveying distance and not least by the characteristic of the material. The relationship between material flow and vacuum flow is usually state as phase densities and is a dimensionless quantity. If the phase density is the same as the bulk density this means there is no air in the conveying pipeline and that the pipeline is blocked. The converse also applies. If the phase density is equal to zero, there is no material in the conveying pipeline. Between these two limits a range of phase densities may occur.


Dense phase means that the material is transported in separate plugs along the conveying pipeline. For most materials, phase density is a factor above ten for dense phase. Some material can be transported in dense phase. Another conveying phase is dilute phase Phase density is usually below ten. Conveying speed in dilute phase is usually > 10m/s The figure below shows conveying phases with different phase density. From very dilute phase (no.1), over dense (no. 6- 8) to blocked pipeline.

Flow direction

Flow direction

* Phase density =

Kg material /h Kg transport air/ h

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Material Flow

It is generally the case that in dense phase, because the material moves in the from of plugs, the vacuum level is usually 30-65%, while in dilute phase it is 10-30%. When sizing a conveying installation, it is important to find the optimum conveying phase for a specific material. A common misapprehension is that the greater the vacuum flow, the higher the material flow. The relation between material flow and vacuum flow may for example be as shown in the figure opposite. The diagram show that the maximum material flow Qmax is equivalent to a vacuum flow Qv. When vacuum flow increases, material flow will decrease. When sizing a conveying installation, it is important to find the optimum point on the curve. The only way of ascertaining the position of maximum material flow for a specific product is to experiment with varying degrees of aeration and vacuum flow. For this purpose many manufactures have special test plants. Qv Q Qmax


Q Material Flow

Vacuum Flow

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Material classificationWhen sizing a conveyor, it is important to determine the fluidity of the material which shall be transported. To sum up the following points should be included in material classification.


Fluidity/angle of repose Bulk density Abrasion factor

Particle - size - distribution - form - density - hardness

Moisture sensitivity (hygroscopic) Explosion hazard Harmfulness/ Poisonous

FluidityThe fluidity is one of the most important qualities when the transport possibilities of a material shall be decided. One way of making a rough assessment of fluidity is to determine the materials angle of repose by pouring out the material from a height and measuring the angle (a) A small angle of repose means good fluidity and a large angle of repose, poor fluidity. The factors which determine the fluidity of the material are particle size, geometric shape, tendency to pick up static electricity and degree of moisture sensitivity. Plastic granules generally have good fluidity while corn flour has poor fluidity and is also sensitive to moisture.

a

Material with poor fluidity can often be fluidized. For fluidization to work, the material must be reasonable fine so that it is lifted by the fluidizing air. If the material consists of coarse particles, fluidization will not be so effective.

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Bulk DensityThe term bulk density refers to the weight/volume of a material, in other words how much one liter of the material weights. As one liter of powder contains both material and air, the bulk density will vary considerably depending on how closely a particular material is packed. In other words, the same material will have different bulk density values if you weight a liter of material that has been poured into a beaker and a liter of material that ahs been shaken and packed together. It is therefore important to measure bulk density under conditions that are as similar as possible given the conveying conditions.


ParticlesIndividual particle weight, size, distribution, form and hardness are all parameters that determine a materials flow ability and thus its conveying characteristics. The weight (density and size) of the individual particles determines what vacuum flow is required to lift the material into the conveyor tube and move it forward in the pipeline. The Term particle distribution refers to how much of various size particles, from the smallest to the largest, make up to materials composition.

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Moisture sensitivityDifferent materials are more or less hygroscopic. If test-running is carried out on a particular material it is important that the conditions are kept as similar as possible to those that will apply on installation. A moisture-sensitive material may form lumps that catch in the material intake, stick in the pipeline or block up the filter.


Tendency to ExplodeIn connection with the handling of finely ground material, there may be a risk of dust expositions. Dust explosions can occur when certain types of particles are mixed with air at the correct ratio and pressure increase are the characteristics of dust explosions. Dust explosions that occur when materials are conveyed are commonly caused by sparks from static electric discharge. In a vacuum conveyor, the ratio of the air-to-material mixture (phase density) varies and the risk of achieving a dangerous mix cannot be eliminated entirely. The risk of ignition can, on the other hand, be minimized by preventing electrostatic discharge and thus the generation of sparks. This can be achieved by connection the various parts of the conveyor system to the same earth point (equipotent connection). Aluminum Aspirin Cotton Iron Cocoa Coffee Cork Carbon Flour Nylon Sugar Grain Tea Wood

Many common material have a tendency to cause dust explosions. Examples of such material are give as above. A complete list may be found in the above-mentioned statute book published by the board for occupational safety and health

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Harmfulness and toxicityA vacuum conveying system is appropriate for conveying harmful materials, as any leakage in the system

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does not allow material to leak out into the surroundings because of the lower pressure within the system. The air extracted from the system may need to be filtered particularly carefully by means of a special filter or piped away to a central filter system.

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The components of the vacuum Conveying SystemA vacuum conveying system always consists of a number of components. The components are suction point, conveying pipeline, collecting, filter, vacuum pump and control equipment. Support components may be fluidization, pipeline valves, various sack dischargers, weighing equipment, etc.


The suction point

The suction point can be a manual operation and would consist then of a straights suction tube.

The suction point can also consist of a feed nozzle, which entrains extra air to the transport.

For automatic or semi-automatic systems a feed station or different type of feeding adapters can be used. A feed station is a special feeding adapter which can mix air to the material and con, if necessary, be provided with fluidization.

For more coarse material a simple feeding adapter can be used.

For bridging materials and where fluidization is unsuitable a rotary valve can be used.

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The conveyor pipelineOne of the many advantages of pneumatic conveying systems is that they are simple to install. Friction in tubes and hoses can reduce the material flow considerably. For permanent installation, rigid tubes should always be used. Tubes have lower friction than hoses. A good tube installation may mean an increase in the material flow so that pump capacity can be reduced and thus lower running costs achieved.


Collection containerThe collection container is the vessel or volume that is place under vacuum in connection with the suction cycle and in which the material is collected. At the bottom of the container there is a discharge device that opens when the suction cycle is complete and the material flows out and then closes again in preparation for the next suction cycle.

FilterWhen the material, together with the conveying air, enters the container, most particles are separated out when the speed of the material drops. The remaining particles follow the air up to a filter where they are filtered out and the clean air continues out though the vacuum pump. Most filters are fitted with some kind of cleaning device.

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Vacuum PumpThe heart of the system is the vacuum pump which creates the reduction in low pressure or suction that moves the material. By using a compressed air-driven vacuum pump, a complete unit is achieved that is explosion-proof and this is important for avoiding dust explosions. Vacuum pumps driven by compressed air also have the advantage of being virtually maintenance-free, silent and not emitting and heat. They are also easier to control as they react very quickly. The pump can be controlled by means of the compressed-air supply, which means that the pump only runs during the suction period and it at rest, saving energy, at other times.


Control equipmentAs a vacuum conveyor works intermittently, some from of control equipment is required that regulates running time, standstill time, discharge, fluidization and etc.

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System StructureAs mentioned previously there are many parameters that affect a vacuum conveying system. Naturally the system structure itself is also extremely important. However, as most vacuum conveying system are unique it is hard to give direct instructions. Certain general basic principles do of course apply and the most important of these are described below.


GeneralSome general rules to bear in mind when planning a vacuum conveying system are: Short conveying distance reduces system and running costs. Keep pipe bends to a minimum to reduce system and running costs. Avoid running the conveying pipeline on an inclined plane. Use rigid tubes where possible.

Suction point designIn order to be able to suck material into a conveying pipeline and then convey it, the conveying air must have a certain minimum speed. Most materials need additional air in order to set them in motion. If a system is to function satisfactorily, the feed, i.e. the suction point, must be designed correctly. It is important that the material is placed close to the intake on the conveying pipeline as the suction capacity decreases by the square of the distance. (Please see side figure.)

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Suction point designWhen the suction points is designed as a feed station, there are normally two valves, one for air and one for the material which can be controlled to give the right proportions of material and air in the pipeline. Another way of supplying air, particularly with material that is hard to convey, is to fit the feed funnel with fluidization.


If

a suction nozzle is used, the simplest way of supplying

additional air is by using a double-mantled Feed nozzle, where the input air is regulated by means of a damper on the handle. The inner tube can also be regulated upwards and downwards in relation to the outer one, and this setting also has an effect on conveying. (Please see side figure.)

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Automatic aspirating valve unitWith the help of a T-piece, vacuum switch and valve, additional air can be introduced into the conveying pipeline automatically. In the first part of the conveying pipeline, a Tpiece is fitted (exactly where depends on the material). On the open part of the T-piece, a valve is fitted which is controlled by vacuum switch. The vacuum switch senses the vacuum level in the conveying pipeline and when the set value is reached, the switch gives a signal that opens the valve and lets air into the system. To protect the conveyed material from contamination, the inlet is fitted with a filter.


Pipe bendsA large bending radius is one way of avoiding unnecessary wear and pipeline resistance. Hoses are often used in bends so that they can be replaced simply and cheaply when they wear out.

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Pipe dimensionsTube diameter is of vital importance for the capacity of a conveying system. In principle the greater the diameter of the tube, the greater the capacity of the system, provided the speed is kept constant. In practice this means that if you want to increase the capacity you usually have to overhaul the entire system, including vacuum pump and containers as well as tube dimensions. In certain cases, however, a capacity increase may be obtained with smaller tubes and the same pump. This is due to the fact that it may be possible to move the material in another phase (dense phase).


The ratio of the various tube diameters is shown by the adjacent figure. For example, a tube with a 75mm diameter is equivalent to two tubes with a diameter of 50mm.

Te speed of the material is directly related to the speed of the air in the pipeline. As the pressure in the pipeline falls the closer you get to the conveyor, the speed of the air and the material increases correspondingly. That is why in certain cases stepped pipelines have to be used (tubes of increasing diameter) to keep down the speed of the material to stop it being broken to pieces.

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Pipe jointsPipe joints must be constructed correctly so that material does not build up around the joint. Rounded edges and a good seal are important points to remember.


Emptying the pipelineVacuum conveying systems can lift materials through relatively large vertical distances, 10-20m, and in some cases even higher. As the conveyor works intermittently there is a risk that when the pump stops and the material falls down, a plug will form at the bottom of a vertical part of the system.

To avoid this tube has to be empted from time to time from the beginning of the vertical right up to the conveyor. This may be achieved by inserting a valve before the rise that can be opened to let in air. This means no material is conveyed before the rise and all material is discharged from the tube up to the conveyor.

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FluidizationIn cases where the material to be conveyed has poor flow ability, fluidization may be an option. Fluidization my take place both at the feed station, to ensure supply of material to the conveyor, and in the conveyor container to improve discharge. Fluidization means that compressed air passes through a porous filter material where it is finely distributed. The finely distributed air creates a cushion or film that reduces the friction between material and base quite considerably. What is more, the air is mixed with the material in such a way that the friction is also reduced between the particles in the material, which means that the material flows like water. Not all materials can be fluidized.


WeighingChecking or weighing how much material has been conveyed may take place according to three main principles. The feed station can measure how much has been taken away, the conveyor container can be weighted to measure how much has reached its destination and the receiving container may be weighed to ascertain how much ahs been discharged. Usually the last weighing option provides greatest accuracy. The degree of accuracy that can be achieved with the various systems is entirely dependent on the properties of the material conveyed and the construction of the system. In cases where the aim is to meter out a certain quantity of material it is best to place special metering equipment on the market and the properties of the material determine type and make.

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Regulation and ControlAll vacuum conveying systems require some form of control, that my be designed in many different ways depending on industry and application. Control may be fully pneumatic (suitable where there is a risk of


explosion, for example), fully electrical or a combination of both. The system may be a separate unit with independent control or part of a larger system where slave units receive signals from the main system. Normally, vacuum conveying takes place intermittently (in batches) and more or less automatically and a cycle may have the following appearance: The vacuum pump starts The bottom valve closes The material is conveyed (any pipeline-discharge valve is opened) The vacuum pump stops (the material is weighed, if the conveyor is weighed) The filter is cleaned (fluidization, if any, starts) The bottom valve opens Product is discharged (fluidization, if any, stops)

The time between the various events are different for different materials. The conveying period per batch is determined mainly by two parameters, the volume of the container and the pressure drop over the filter. Opening of the pipeline-discharge valve is determined by conveying speed and the distance to the conveyor. How long the bottom valve is open depends on how easily the material runs out.

Pneumatic Controller

Electronic Controller

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Various special devicesA conveyor may be fitted with a rotary valve so that it can be run continuously. Another method of obtaining continuous material flow is for two conveyors to be run alternately in what is known as a twin set. In a twin set the conveyors are controlled in such a way that while one is sucking the other one is discharging. On changeover there is an overlap period when both conveyors run together for a short time. Sometimes continuous conveying may be obtained by eliminating the separate container and conveying directly down into a vacuum-proof vessel.


Several different materialsIt is simple to connect a vacuum conveyor to different feed stations and thus it can convey different materials to one and the same container, but only one material at a time. If you want to mix different material to a recipe, the system can be fitted with load cells fro weighing.

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TablesExpressions and UnitsIn everyday speech many different expressions and units are used for both pressure and flow. It is important to agree on what is meant by them.


Negative / Positive PressurePressure P = F/A (Force/Area) Important unit: psi SI unit (system international unites) : Pascal (pa). 1 Pa = 1 N/m2 Common multiple units: Gpa, Mpa, kPa, mPa, Pa

Pa(N/) 1 100000 98066.5 9806650 133.322 101325 6894.76

bar 0.00001 1 0.980665 98.0665 1.33322x10-3 1.01325 68.9476x10-3

Kg/ 10.1972x10-6 1.01972 1 100 1.35951x10-3 1.03323 70.307x10-3

Torr 7.50062x10-3 750.062 735.559 73.5559 1 760 51.7149

Psi(1bf/in2) 0.145038x10-3 14.5038 14.2233 1422.33 19.3368x10-3 14.6959 1

1torr=1mmHG at 0 1mm column of water = 9.81pa

Different terms for pressure in relation to absolute vacuum P+ PI=pressure air pressure Po=0-pressure absolute vacuum P+= pressure above atmospheric Pa=absolute pressure P-= pressure below atmospheric Pa P1

PP0

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Pressure below atmospherickPa Sea level 100 101.3 1000 mbar 1013 700 600 500 50 400 300 200 10 Absolute vacuum 0 100 0 100 0 101.3 Torr 760 -10 -20 -30 -40 -50 -60 -70 -80 -90 600 700 760 30 400 500 -15 -20 -25 -kPa 0 -mmHg 0 100 200 300 -5 -10 -inHg 0 10 20 30 40 50 60 70 80 90 100 % vacuum 0


500

Pressure above atmospheric

kPa1000 10

bar145

psi

Kp/10.2

100 500 5 50 5.0

100

1

10

1.0

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Change in atmospheric pressure with altitude (height above sea level)A vacuum gauge is normally calibrated with normal atmospheric pressure at sea level as a reference, 1013.25 mbar, and is influenced by the surrounding atmospheric pressure in accordance with the table below.


Barometric pressuremmHg593 671 690 700 710 720 730 740 750 760

The reading on the vacuum gauge at 1013.25m (760 mmHg)-60kPa39.0 49.4 52.0 53.3 54.6 55.9 57.3 58.6 59.9 60.0

mbar790.6 894.6 919.9 933.3 946.6 959.9 973.3 986.6 999.9 1013.25

Equiv m above sea level*2000 1000 778 655 545 467 275 200 111 0

-75kPa54.1 64.5 67.0 68.3 69.7 71.0 72.3 73.7 74.9 75.0

-85kPa64.1 74.5 77.0 78.3 79.7 81.0 82.3 83.6 84.9 85.0

-90kPa69.1 79.5 82.0 83.3 84.7 86.0 87.3 88.7 89.9 90.0

-99kPa78.1 88.5 91.0 92.3 93.7 94.9 96.3 97.7 98.9 99.0

* At normal barometric pressure The vacuum gauge shows the differential pressure between atmospheric pressure and absolute pressure. This means that the gauge shows what vacuum level is available at different heights.

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Diagram showing atmospheric pressure at varying heights above sea level

100000

Meters above sea level


10000

1000

100

0

200

400

600

800

1000

1200

mbar

Energy requirement on increased vacuumThe diagram illustrates the energy requirement on increased vacuum. As can be seen, the energy requirement increases drastically above -90kPa, which is why a vacuum level below this is always advisable.

100 Pressure below atmospheric -kPa 90 80 70 60 50 40 30 20 10 0 1 10 100 1000 10000 100000 1000000

Energy factor

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Vacuum ConveyorL/s 1 2 /min 0.06 0.12 0.18 0.24 0.30 0.36 0.42 0.48 0.54 0.60 0.66 0.72 0.78 0.84 0.90 0.96 1.02 1.08 1.14 1.20 1.50 1.80 2.10 2.40 2.70 3.00 /h 3.60 7.20 10.80 14.40 18.00 21.60 25.20 28.80 32.40 36.00 39.60 43.20 46.80 50.40 54.00 57.60 61.20 64.80 68.40 72.00 90.00 108.00 126.00 144.00 162.00 180.00 cfm 2.12 4.24 6.36 8.47 10.59 12.71 14.83 16.95 19.07 21.19 23.30 25.42 27.54 29.66 31.78 33.90 36.02 38.13 40.25 42.37 52.97 63.56 74.15 84.74 95.34 105.93

FlowsFlows, volume per unit of time. Quantity designations: Q, q, =V/t (Volume/time) SI unit: cubic meters per second (m3/s). Common multiple units: l/min, l/s, m3/h.

3 4 5 6 7 8 9


/s1 0.28x10-3

/h3600 1 0.06 3.6 1.6992

L/min60000 16.6667 1 60 28.32

I/s1000 0.2778 0.0167 1 0.4720

ft3/min(cfm)*2118.9 0.5885 0.035 2.1189 1

10 11 12 13 14 15 16 17 18 19 20 25 30 35 40 45 50

* 1 ft = 0.305m

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Higher environmental standard set for industryIncreased awareness of the environment means that individuals and companies alike see their everyday activities in a new light. Heavy, manual handling of sacks can cause repetitive strain injuries and also often leads to a dusty atmosphere with a risk of dust explosions. Even materials that are harmful to health are sometimes handled in this primitive way. Its not hard to imagine what this means for the well-being of the personnel in the long term. Today VTEC can offer alternative solutions with a wide range of various vacuum conveyors that meet high standards of hygiene, reliability and economy.


Vacuum Conveying a simple way of moving materialSuitable for powder, granules or liquid productsNow you can avoid heavy lifting and a dusty atmosphere. Using vacuum for moving material is not as strange as it sounds. In principle the technology is the same as with an ordinary vacuum cleaner, although material and applications are different. We have tested many materials, ranging form flour, rice and plastic granules to apple sauce and jam. In our laboratory we are able to test different conveying distances and materials to simulate a wide range of requirements and applications. Test results are evaluated and conclusions drawn to make it much easier to determine the size of an installation and to choose accessories and control system

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Acetylsalicylic acid Aluminum oxide Apple sauce Apricot stones Aromic salt Baking-powder Bath salts Beans, wheat Blueberries, frozen Bone glue Buckwheat flakes Calcium phosphate Cane-sugar Celit Cement Chalk Cheese powder Chewing gum

Chicken liver Chocolate powder Chromite sand Cocoa beans Coffee Corn flour Cosmetic powders Debrisan Detergents Dextrin Enamel raw material Expancel Felspar Ferrous carbonate Fertilizer Fish food Floating putty Fluxing material

Fumaric acid Gelatine Ginger Grape-sugar Graphite powder Gun powder Gypsum Herb tea Iron oxide Kieselguhr Lactose Liver salts Magnesium oxide Metal flakes Mica Milk powder Mustard seeds Nickel powder

Nutmeg Peas

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Penicillin Plastic granules Polyethylene powder Potato flour Powdered blood Powdered resin PVC powder Rice Rock-salt Salt Sand Sawdust Soya meal Spices Wheat grains

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The principle of VTEC vacuum conveyor1. 2. 3. 4. 5. Exhaust valve is closed and vacuum in created by the compressed air driven VTEC vacuum pump a negative pressure is created in the Receiver Tank. A negative pressure is created in the pipeline. From the suction point the material with air is sucked into the receiver tank. The filter effectively prevents dust and small particles from entering the pump. During the suction period a small reservoir mounted in the filter unit is filled with compressed air. When the material container is filled, the vacuum pump stops. The exhaust valve of the conveyor opens and the material inside is discharged. At the same time the compressed air in the reservoir is released to blow the filter clean automatically. When the pump restarts, the cycle is repeated suction and emptying are normally controlled with a timer, but other control signals can also be used.


6.

V-tec compressed Receiver tank Exhaust valve Filter Pipeline Suction point Control unit Reservoir (air tank)

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Why do technicians choose VTEC vacuum Conveyors? Minimal maintenance Low noise level Automatic filter cleaning system Low energy consumption Simple to install Compact size Easy to clean Dustless conveying Made of acid-proof Polished steel Easy to maintenance Light weight Easy to installation Quick deliver (stock)


You can choose between six different basic modelsVTEC 100 VTEC 200 VTEC400 VTEC 600 VTEC 800 VTEC 1200

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Guidelinefor VTEC vacuum ConveyorHIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY

Note: As each material is unique and there are variations in the construction of the plant, deviations may occur.

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1. Conveying length and capacityThe power requirement (Pm) is the product of the total conveying length (L) in meters (m) and the capacity (Q) in ton/hour (t/h) Pm = L x Q L = the sum horizontal as well as vertical conveying. This applies to L > 4m < 30m, and with a bulk density of = 0.5 1.8 ton/m3. Particle size < 5mm. In other case, please contact KPS(VTEC)


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2. Pm-figure / ConveyorExample


Sugar will be conveyed from a silo to a filling machine. The distance is 8m and the conveying height 3m. The total conveying length, L = 8 + 3 = 11m, and the desired capacity is 1.3 ton/hour: The effect figure (Pm) will be 11 x 1.3 = 14.3 As to the description below a VTEC vacuum conveyor VTEC 400 will be the nearest choice, with the Pm = 10-20.

Pr = 3-6 VTEC 100

Pr = 5-10 VTEC 200

Pr = 10-20 VTEC 400

Pr = 20-30 VTEC 600

Pr = 20-40 VTEC 800

Pr = 30-50 VTEC 1000

Pr = 30-60 VTEC 1200

VTEC 100

VTEC 200

VTEC 400

VTEC 600 ~ VTEC 1200 1200

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3. Equipment / Material propertiesExample 1Material with 50% particle size > 0.2mm < 5mm

Example


Plastic granules Granulated sugar Rice Mustard seedsPneumatic Control VTEC100-AC VTEC200-AC VTEC400-AC VTEC600-AC Electronic Control VTEC100-EC VTEC200-EC VTEC400-EC VTEC600-EC VTEC800-EC VTEC1200-EC

Example 2

VTEC800-AC VTEC1200-AC

Material with 50% particle size < 0.2mm (larger filter area for dusty material) Good fluidity

Example Table-salt Polyethylene powder PVC-powder

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Example 3 -3


Material with 50% particle size < 0.2mm Bad Fluidity Building Bridging Flocculent (Fluidization)Pneumatic Control VTEC100-AC VTEC200-AC Electronic Control VTEC100-EC VTEC200-EC VTEC400-EC VTEC600-EC VTEC800-EC VTEC1200-EC

Example Potato Flour Magnesium stearate Milk powder Wheat-flour

VTEC400-AC VTEC600-AC VTEC800-AC VTEC1200-AC

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Vacuum Conveyor

4. Pipe dimensioning/ components (Accessories)HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY At conveying lengths < 30m* When handling heavy materials with a bulk density > 1 ton/m3 a pipe of small dimension should be chosen, and for light materials < 1 ton/m3, a pipe of larger dimension should be chosen

Type VTEC100 VTEC200 VTEC400 VTEC600 VTEC800 VTEC1200

ton/ 22 32, 40 40 40, 50 50 50, 75

30 m, contact VTEC.

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Vacuum Conveyor

MaintenanceVTEC vacuum conveyors are designed and manufactured to work with minimum service and maintenance. To ensure reliable operation for many years a few simple checks and measures are, however, required. Please note that maintenance may vary considerably depending on operating environments, standards of hygiene and the properties of the material conveyed.


Maintenance intervalsDaily Check the feed pressure of the compressed air Check pressure drop in connection with material conveying Wash or clean (for certain food applications)

Monthly Check the pressure drop when running without material Check for leaks in the conveyor and tube system Wash filters (experience may indicate other intervals)

Every other month Replace filters (experience may indicate other intervals)

Every six month Dismantle, clean and check (experience may indicate other intervals)

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Vacuum Conveyor

Maintenance intervalsIntervals by experienceEach application is unique in the amount of inspection and maintenance it requires. In most cases, the user himself will therefore build up his own experience of the time intervals between important maintenance points. Filter washing Filter replacement Dismantling, washing, cleaning and checking


WarrantyThanks to the simple yet functional construction of our products with few moving parts and only well tried materials and components, we provide a 5-year warranty on conveyors and vacuum pumps. For accessories the guarantee period is 1 year. The guarantee does not apply to filters or wear parts such as material hoses, tube bends and several other kinds of accessories.

HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGY HIGH QUALITY VACUUM TECHNOLOGYVacuum Conveyor

VTEC vacuum conveyor application

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Application-1

Application-2



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Application-3

Application-4



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Application-5

Application-6



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Application-7

Application-8



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Application-9

Application-10



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Application-11

Application-12


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VTEC Vacuum conveying system

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