Cassava Peeling Machine by Outer Drum System

Cassava Peeling Machine by Outer Drum System - Cassava structure is the outer skin, the inner bark, cambium, meat and core. Section which can be used to trade commodity is the main part of the flesh, as it has a higher content of carbohydrates, for the outer skin of the flesh and the skin should be peeled first. Pieces of meat used as a raw material of cassava processing industry. Cassava processing industry generally accepts that cassava have been peeled, so that the peeling process should be carried out directly by farmers or collector.

Cassava peels means of separation of the outer skin and the inner skin of cassava meat. Peeling of cassava has become a regular activity for cassava farmers before being sold to the agricultural product processing industry. This is done in order to obtain a higher cassava sale value. Most farmers are manual peeling directly using a knife.

Development of technology for cassava peeling machine in the agricultural industry remains very low and still limited to only peel the shell. Peeling process uses centrifugal force to rely on the friction cassava between the drum and cassava together. In fact, the friction force is only able to peel the shell only reason for peeling the inner skin should use a sharp knife.

This article will modify its machine in several respects:

• Added static shaft (inner drum) in the center of the drum so that rotation of the outer drum is more stable and robust.
• Added cassava direction on shaft, cassava so that the movement of the blade that is directed into the outer drum, so expect the peeling process will be faster.
• Added a knife within the outer drum, so that not only the shell peeling cassava, but the inner skin can be peeled.

Therefore, this machine is called Cassava Peeling Machine by Outer Drum System.

Construction of Cassava Peeling Machine

Modification process produces construction machine as in the image below.

Construction of Cassava Peeling Machine

Cassava Peeling Concept

Cassava peeling machine uses a peeling drum mounted knife inside. Peeling drum consists of two parts: the outer drum and the inner drum. Outer drum moving dynamically while the inner drum was static. Outer drum is constituted by a strip plate shaped circular as the surface of the inner tube and is given as a peeling knife, while the inner drum comprises a steering shaft with a plate.

When the outer drum rotating and there was cassava, cassava and then just turn tends to lead to the outer surface of the drum due to the influence of centrifugal force. Inner drum is equipped with a steering board will resist movement of cassava, so that the knife is inside the outer drum tear cassava skin. When some existing cassava peel hand then peeled cassava to be easily detached due to the friction cassava between the direction, cassava between the outer drum and cassava together.

Operation of Cassava Peeling Machine

How to use cassava peeling machine is done by the following steps:

1. Turn the peeling drum manually until the door is at the top.
2. Open the drum peeler gate.
3. Put cassava into the peeling drum.
4. The quantity of cassava which included should not exceed 3/4 drum peeling capacity because it will reduce the centrifugal force.
5. Close the peeling drum door and locked.
6. Turn on the electric motor to rotate the peeling drum.
7. When the peeling process occurs in the outer drum, cassava peels off gate out by outer drum space and through the outer funnel.
8. Turn off the electric motor when the peeling process is complete.
9. Turn the peeling drum manually until the door is at the top.
10. Open the drum peeler gate.
11. Remove out the cassava form peeling drum.

That is a description about the Cassava Peeling Machine by Outer Drum System. If you find misconceptions in this post, please provide the correction in the comment box.

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V-Belt Selection Guide: V-belt Sizes, Types and Safety

V-Belt Selection Guide: V-belt Sizes, Types and Safety - Belts are made of rubber with a cotton cloth core or the like as reinforcing the greatest tensile force. Use as v-belt transmission has the following advantages:

• A portion of the belt is twisted in the pulleys experience a wide arc so that grow large section to provide a large friction.
• The friction force also increases due to the influence of the wedge-shaped which generate a large transmission power of relatively low stress.
• It has a slip to avoid damaging an electric motor.
• It can be used in a large transmission ratio and the distance closest to the shaft.

V-belt is a standard part so easy to find in stores or belt manufacturer's dealers. The machine designer simply chooses the type and size of the belt as required by the machine. V-belt selection is determined by the length and type of the cross section of the belt relative to the power and speed are transmitted. Once selected, the belt also remains to be tested for safety by the power capacity and the speed of the belt.

Determined of v-belt types

V-belt has a trapezoidal section with a variety of sizes, from small to large, ie, type A, type B, type C, type D and type E. The v-belt types sections selected based motor  power and driver shaft speed by the following curve.

Examples:
If the belt driven by a motor with a power of 3 kW at a speed of 2000 rpm pulley, then the graph above corresponding the intersection of the power requirement line (blue line) with the speed of driver pulley (red line) is in the region A means that the type of belt is selected by type A.

Determined of v-belt sizes

Once the type of v-belt is known, the following must be known how long the belt is required. In the trade standard, long belt is expressed by v-belt sizes. The v-belt size is units of inches in circumference around length, not decimals and fractions. Before determining the v-belt sizes, the v-belt must be known mm in length using the following calculation:

Note:
L = V-Belt Length (mm)
C = Center Distance (mm)
d = Diameter of driver pulley (mm)
D = Diameter of driven pulley (mm)The v-belt size is obtained by converting the circumference of belt in inch units. Its results are rounded. For example, if you get 24.45 inches then take a belt number is 25.

V-belt safety by power capacity

Belt has a power capacity that can be transmitted. Power capacity issued for each single belt depending on the v-belt type, pulley diameter, speed of the driver pulley and belt marks. Belt manufacturer usually have the belt capacity catalogue. An example of a table for the power capacity of the v-belt type A shown.

Power capacity of v-belt is main value in table and value added suitable of transmission ratio, example if driver pulley speed is 600 rpm, pulley diameter  is 100 mm and transmission ratio is 1,5 so power capacity of v-belt is 0,77 + 0,06 = 0,83 kW.

V-belt safety is sure if belt capacity in the table is greater than the actual belt capacity. The actual belt capacity can be calculated by the following equation:

Note:
Pr = Actual belt capacity (kW)
P = Power requirement (kW)
N = Number of belt
k = Correction factor

The v-belt correction factor is obtained by following table:

Safety of v-belt speed

V-belt safety can be seen from the ability to withstand the transmitted speed. Generally, the belt speed can be provided for every 10 to 20 m/s and up to 25 m/s with a maximum power which can be transmitted is less than 500 kW. This means that the belt can be considered safe, if its speed is less than 25 m/s (v <25 m/s).

That is a description about how to determine of V-Belt Selection Guide: V-belt Sizes. Types and Safety. If you find misconceptions in the v-belt design, please provide the correction in the comment box.

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Belt Conveyor Design: Capacity, Power Required and Pulley Size

Belt Conveyor Design: Capacity, Power Required and Pulley Size - Conveyor used to move material from one location to another as needed. Belt conveyor is of a type which uses a belt as a support material which is driven by motor and other components of the conveyor. Belt conveyor can be used to carry unit load and bulk load in an upright position or inclination angle.

Several parameters are used in the calculation of the conveyor belt that the capacity, power requirement and pulley size.

Belt conveyor capacity in upright position

Belt conveyor capacity is the amount of material transported tons per hour (tph). The conveyor capacity in upright position may be formulated as follows:

Note:
Q = Conveyor Capacity (tph)
A = Cross-sectional area (m2)
v = Belt velocity (m/min)
γ = Material density (Ton/m3)

Cross-sectional area is belt area which formed by tension bracket and angle of surcharge. Value of cross-sectional area is affected by angle of through, belt width and angle of surcharge, as indicated in the following table.

Belt conveyor capacity in angle inclines position

Note:
k = Inclination Reduction Rate

Value of Inclination Reduction Rate is indicated in the following table.

Power requirements for belt conveyor

Power required to drives the belt that transports the transfer material. Power requirement (P) calculated according to the effective force belt (Fe) with the following formula:

Note:
P = Power Requirement (Watt)
Fe = Effective Force (N)
v = Velocity (m/s)

Effective Force is calculated by multiplying the weight of components on the conveyor (material, conveyor belt and drum pulley) with the gravity and coefficient of friction with the following formula:

Note:
Fe = Effective Force (N)
µR = Coefficient of friction
g = gravity (m/s)
M = Material weight (kg)
Mb = Belt weight (kg)
Mr = Drum pulley weight (kg)

The coefficient of friction depends on the type of the support belt and pulleys are used as shown in the following figure.

Material weight (M) is calculated based on the volume of the multiplication with the density of the material or to the following formula:

Note:
M = Material weight (kg)
A = Cross-section area (m2)
L = Conveyor Length (m)
γ = Material density (kg/m3)

Determined of pulley size for belt conveyor

Pulley size is closely related to the speed of the conveyor. In the design of pulley, the minimum diameter of pulley can be calculated by the formula:

Note:
Dm = Minimum diameter of pulley (mm)
F = Maximum Force (N)
C2 = Correction factor 2
B = Belt Width (mm)
ß = Pulley angle (degrees)

The value of correction factor 2 as a function of the pulley as in the following table.

Maximum force (F1) is a multiplication factor between the effective forces (Fu) with a correction factor pulley 1 to the following formula:

Note:
F = Maximum Force (N)
Fe = Effective force (N)
C1 = Correction factor 1

The value of correction factor 1 as a function of the pulley as in the following table.

That is a description about Belt Conveyor Design: Capacity, Power Required and Pulley Size. If you find misconceptions in the belt conveyor formula, please provide the correction in the comment box.

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Sand Centrifugal Mixer Machine for Foundry Industry

Sand Centrifugal Mixer Machine for Foundry Industry - One step in the casting process is to make the molds. Shaped molds to form the foundry mold cavity. The most commonly used molds for metal casting are sand molds. Molding sand is typically composed of base, such as quartz sand and binders materials such as clay or bentonite. In addition, to improve the quality of the molding sand often added to other materials such as coal dust, sawdust, flour, etc. All mold materials were mixed using a mixer machines, the purpose of all the ingredients can be mixed uniformly. If the molding sand of the water content does not meet the standards, add water if necessary when the ingredients are mixed.

Sand mixer machine used in the foundry industry typically uses a wheel and blade type mixer. Wheel type usually called sand muller mixer is a mixer with two wheels moves the rotation and revolution. Blades types usually called sand centrifugal mixer is a mixer with blades as the sand mix. This article will explain the sand centrifugal mixer for foundry industry.

Construction of Sand Centrifugal Mixer Machine

Sand centrifugal mixer construction can be seen in the image below:

Construction of Sand Centrifugal Mixer Machine

Main sand centrifugal mixer component corresponds to the above construction, including:

1. Electric motor serves as the main driver of machine. 
2. V-Belt transmission serves to reduce the rotation while overcoming overload.
3. Gear Box, used to reduce the rotation of the blade with a large comparison.
4. Double Blade serves as a primary raw material mixture.

Centrifugal mixer concept

Mixing process occurs when raw materials are in the top of the rotating blades. The blade is angled approximately 45 degrees, so that when the centrifugal force of rotation and provide pull-up. The centrifugal force causes the material first expelled, bounced off the wall and towards the center. Upward force causes the raw material thrown up and down due to the gravity of the first material. The movement of raw materials continuously mixed raw materials uniformly.

Principle of Sand Centrifugal Mixer Machine

Sand Centrifugal Mixer Machine operates on the basis movement from the electric motor. Electric motors drive the knife through two transmission systems are v-belt and gear. The transmission system is capable of reducing the ball comparison 1/20 or reduces the rotation of the blade about 75 rpm. The value of the rotation of the blade causes a sufficiently large torque, thus providing a centrifugal force and an upward force sufficient for mixing the raw material to the thrust of the hopper.

Operations of Sand Centrifugal Mixer Machine

The operations of sand centrifugal mixer are: 

1. Prepared the raw materials to be mixed molding sand.
2. Pour the raw material in the hopper.
3. The amount of raw materials should not be greater than 3/4 of the contents of the hopper.
4. Turn on the electric motor,
5. Wait a few minutes until homogeneous commodities.
6. Prepare the tank and place it under the expenses of the funnel.
7. Open handle pass slowly until the load is initiated through a funnel.
8. Turn off the electric motor when all the molding sand is out.

That is a description about the Sand Centrifugal Mixer Machine for Foundry Industry. If you find misconceptions in this post, please provide the correction in the comment box.

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Helical Gear Design: Helical Gear Dimension and Strength

Helical Gear Design: Helical Gear Dimension and Strength - Helical gears used to move between the axes of rotation are parallel. Helix angle is the same in each gear, but the gear is shifted to the right and the other left. Involutes tooth shape is an expectation. A helix is a theoretical line or path generated on a cylindrical surface by a cutting tool which is fed length-wise at a uniform rate, while the cylinder is also rotated at a uniform rate. Initial bias intersection gear teeth are something that has become a more teeth line in the communion of the teeth.

Helical gear design includes the standard dimensions and strength. Standard dimensions are pitch diameter, outside diameter, root diameter and whole depth. The helical gear strength is the ability to withstand the deflection load and surface pressure.

Standard dimension of helical gear

Main gear dimensions are often expressed by the number of teeth (T) and the normal module (M) for the metric. Multiplying two variables leads to what is called the pitch diameter. In helical gears, the value of the pitch diameter is affected by the helix angle with the following relationship:

Note:

D = Pitch diameter (mm)

M = Normal module

T = Number of teeth

ß = Helix angle (o) 

How to determine outside diameter, root diameter, addendum, dedendum and whole depth are equal to spur gear calculation. (Read more : Spur Gear Calculation)

Helical gear strength by deflection load

Deflection load occurs due to the tangential force acting on the tooth surface. Tangential force is the force acting in the direction of rotation of the gear to a point on the pitch circle. Tangential force can be calculated by the following equation:

Note:

Ft = Tangential force (Kg)

Pe = Power estimation (Kw)

V = Velocity (m/s)

Velocity of helical gear can be calculated by the following equation:

Note:

V = Velocity (m/s)

n = Rotation speed (rpm)

D = Pitch diameter (mm)

Deflection load caused by the tangential force should not exceed a bending load per unit width on the sides of the permissible bending stress so that the wheels do not have a broken tooth. Deflection load can be calculated based on the Lewis equation, which is the basis for the gear design which is:

Note:

Fb = Deflection load per unit width (kg/mm)

Sd = Deflection stress (kg/mm2)

M = Normal module

Y = Gear factor

fv = Velocity factor

Helical gear strength by surface load

If the pressure between the surfaces of the tooth is too large, the teeth wear out rapidly. Furthermore, the tooth surface may be damaged because of the repeated fatigue load. Therefore, the pressure on the surface of the tooth or the surface load capacity must be limited. The surface pressure does not exceed the surface load per unit width. The surface load is calculated based on the Hertz theory that the decline in the equation can be obtained by the following equation.

Note:

Fs = Surface load per unit width (kg/mm)

fv = Velocity factor

Sc = Contact stress (kg/mm2)

D1 = Pitch diameter of pinion (mm)

T1 = Number of teeth of pinion

T2 = Number of teeth of gear

That is a description about Helical Gear Design: Helical Gear Dimension and Strength. If you find misconceptions in the helical gear formula, please provide the correction in the comment box.

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Sand Sieving Machine by Vibration Shaker System

Sand Sieving Machine by Vibration Shaker System - Sand is very important and its use in the foundry industry. Sand is the main material in the making of molds. Sand used to make the mold must meet several requirements, including the particle size uniformity which moisture resistance, conformability, plasticity and permeability. One objective is air, steam and gas in the mold is able to leave not cause defects such as porosity products.

Sand usually used derived from nature still mixed with other minerals such as soil, clay, gravel and rocks. Also frequently encountered conditions and sandy gravel sizes are not uniform, even clot. Therefore, for the purposes of foundry sand, natural sand treated first by sieving.

Sand sieving is the process of separation of sands or other classification process of the material grain size. Sand sieving process in foundry industry normally uses the principle of sand vibration sieving machine. The vibration may be derived from a crank system or vibration motor. But in this article will explain the crank vibration system or called Sand Sieving Machine by Vibration Shaker System.

Construction of Sand Sieving Machine 

Sand sieving machine construction consists of several components as shown in the following figure.

Construction of Sand Sieving Machine

Sieving Machine Concept

Sieving machine serves is to remove large grains with a small grain through a sieve. Separation occurs when the sand is placed on top of a filter having holes size. Sand having a size smaller than the sieve pass hole, while the sand having a size larger than the hole in the filter will be trapped in it. Screen over the hole, the greater the retention size in the filter sand. To produce a grain of sand at a uniform size, it should be at least twice the filter. The first sieving is done to get rid of the sand with a larger than standard withholding sand filter is ignored. The second sieving is done to get rid of the sand with a size too small means that the sand filter is ignored. 

Vibration Shaker Concept of Sand Sieving Machine

The concept of vibration shaker takes the concept of gravity, where the material will tend to go down when there is an empty place. A little material will be easier to reach the lower point of large material because the large material will form a larger gap can be easily introduced by small material. Vibration shaker received will displace material and open a wider space and speed up the decline of small material. Therefore, the vibration shaker will make little material moves down, and called the large material for mounting.

Principle of Sand Sieving Machine

This machine combines the principles of vibration shaker and sieving machine. The vibration shaker generated by a crank system that converts rotary motion to translational movement or a back and forth. Forth rounds crankshaft of an electric motor connected by a v-belt. The movement back and forth on a screen made of a material which is on top moves to accelerate the reduction of material in the small hole of the filter and through the line. Sieve construction made with inclined at an angle, so that during the back and forth movement, much material left in the filter is moved through the upper channel.

Operations of Sand Sieving Machine

Work mechanism of the sand sieving machine is as follows:

1. Place sand material through the hopper.
2. Turn on the electric motor.
3. Round electric motor crank drive v-belt transmission.
4. Direction of the crankshaft sieve move back and forth.
5. Sieve movement will sand material spread quickly.
6. Gravel will be retained in the filter and the upper channel
7. Sand filter end jump into the hole and the bottom channel.
8. Input another sand material if the material has some sand in the hopper.
9. Turn off the electric motor when the selection process is completed.
10. Clean the filter residual material is still stuck in the top of the filter.

That is a description about the Sand Sieving Machine by Vibration Shaker System. If you find misconceptions in this post, please provide the correction in the comment box.

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Feed Pellets Machine by Extrusion System

Feed Pellets Machine by Extrusion System - The success of the farm business is largely determined by three factors are just as important is the breeding, feeding and management. However, if you look at the total cost of production of industrial agriculture, the animal feed contribution is the highest at about 75% of them.

Quick farms in Indonesia led to growing food needs. These conditions give rise to new problems in the manufacturing process of feed pellets. Feed pellets have a very complex composition. Its composition is fish meal, corn meal, flour, bran, tofu and vitamins. We must mix these ingredients into one. At that time, the material mixture pellets used still shaken manually by hand and some use a blender.

Manual stirring produce granules are less homogeneous with respect to the use of a mixer. However, these two ways, the pellets produced as irregular massive clots, when that is too large already dried up, we have to reprocess or to destroy. The feed pellets machine so necessary to use the extrusion system, wherein the granules produced in the form of small granules is more homogeneous.

Construction of Feed Pellets Machine

Construction of feed pellets machine as seen in the image below:

Extrusion Concept of Feed Pellets Machine

Screw extruder with pairs of cylinder, while the pellet raw material through in the hopper and is between extruder and cylinder. When extruder turns on the stationary cylinder, it will push out the pellet raw material.

Principle of Feed Pellets Machine

The electric motor drives the main shaft through the v-belt transmission. Extruder promoting exploitation of raw materials pellets placed in the main shaft. The pellets feedstock material put in the hopper and leads to screw extruder in the cylinder. Screw extruder will stir the pellets raw material in the cylinder at the same time push it to the forming filter. Then exit through the funnel outlet in the form of granules pellets.

Operations of Feed Pellets Machine

How to run feed pellets machine are:

1. Prepare raw material, such as fish meal, corn meal, flour, bran and other materials.
2. Combine all the raw materials into a container.
3. Turn on the machine by pressing the ON button.
4. Put mixture of the raw materials in to the feeder.
5. The extrusion system will process the raw material automatically and the row material will out through the filter in the form of granules.
6. Prepare a container to the filter for receiving the granules pellets.
7. If the raw material in the feeder less immediately refilled.
8. Turn off the machine if the decision-pellets are complete.
9. Ensure that all products come in pill form when the machine is off.
10. Clean the machine from rest of the raw material to prevent oxidation.

That is a description about the Feed Pellets Machine by Extrusion System. If you find misconceptions in this post, please give correction in the comment box.

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Dust Collector Design: Air Flow, Static Pressure and Power Fan

Dust Collector Design: Air Flow, Static Pressure and Power Fan - Dust collector is a dust suction or smoke causing air pollution from industrial processes such as melting material, welding, screening the flour, material falling from conveyor to another conveyor and several other processes important applications. In the dust collector, a dirty air filter will separate dust and air. Dust will enter the shelter, while the air out of the plant so that it can cope with air pollution. (If you want to know more about definitions, functions, principles and any types of dust collector, read more: What is a dust collector)

Dust collector can clean the air of many sources of dust and smoke, by performing right calculations will be known air flow needed to suck the dust. In this article I will explain how to design of dust collector system, especially on the calculation of static pressure and air flow required so that can know the power fan of dust collector. As for the other part calculation, I will describe in the next article.

Calculation of Air Flow for Dust Collector Design

Air flow is the volume of air necessary for sucking the dust in the suction area. We must decide a suction area before calculate the air flow. Suction area is the spherical zone which can reach air suction. The outer end of the ball is an area with a minimum speed of the air to suck the dust. Over the suction zone, the greater the volume of air flow necessary. We must put a suction area in place that has the greatest potential for dust presence. If the source of the dust is in a remote part of the intake would be more effective if we divide it into several sections.

Air flow in the suction area can be calculated by the formula:

Note:

Q_i      = Air Flow of Suction Area (m3/hour) 

V_min   = Air Speed Minimum m/s) 

A       = Wide of Suction Area (m2)

d        = Diameter of Suction Area (m)

Value of the air speed least for sucking the dust is depending on the type of dust, the dust density and size of dust particles.

If the dust collector is used to suck the dust at a certain point in the suction zone, the air flow of the dust collector is the sum of the air flow in each suction area.

Note:

Q_t   = Total air flow of Dust collector 

Q₁   = Air Flow in first area

Q₂   = Air Flow in second area

etc.

Calculation of Static Pressure for Dust Collector Design

Static pressure is a loss due to the air flow pressure pickup area to exit the dust collector system. The pressure loss can occur in the suction, pipe duct, elbow and cyclone. Calculation of static pressure refers to duct size.
If the duct is used in the form of a tube, the diameter of ducting pipe can be determined by the formula:

Note:

d     = Ducting pipe diameter (m)

Q_i    = Air Flow of Suction Area (m3/hour) 

v     = Air Speed in the duct (m/s)

Duct in the adjacent suction area must be combined in order to be more effective, as indicated below:

Size of conduit ducts 1 and 2 are calculated using the above formula with sufficient air flow of each suction area. Regarding the size of the tubes 3 is calculated by the formula:

Duct size to the inlet of the dust collector is calculated by the formula:

Static pressure of the dust collector is a number of static pressure at any point of the possible loss of pressure calculated with the following formula:

Static pressure in the suction area or free entrance

Static pressure in the straight duct

Static pressure in the elbow duct

Static pressure in the cyclone, its value determined is 800 Pa.

Note:

ΔP = Static Pressure (Pa)

v     = Air velocity (m/s)

λ     = Duct friction

l      = Pipe length (m)

d     = Pipe diameter (m)

γ     = Air density (kg/m2)

g     = Gravity (m/s2)

Calculation of Power Fan for Dust Collector Design

Calculation of power fan can use the following formula:

Note:

P     = Power Fan (kW)

Q    = Total Air Flow of Dust collector 

ΔP  = Static pressure (Pa)

η     = Motor efficiency

If a fan using a standard factory specifications, then you only need to give the data of air flow and static pressure for fan supplier and they will decide its fan.

That is a description about the Dust Collector Design: Air Flow, Static Pressure and Power Fan. If you find misconceptions in this post, please give correction in the comment box.

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