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Hoist application in engineering field
A hoist is a device used for lifting or lowering a load by means of a drum or
lift-wheel around which rope or chain wraps. It may be manually operated,
electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting
medium. The load is attached to the hoist by means of a lifting hook.
Types of hoist:
The basic hoist has two important characteristics to define it: Lifting medium and
power type. The lifting medium is either wire rope, wrapped around a drum, or load-
chain, raised by a pulley with a special profile to engage the chain. The power can
be provided by different means. Common means are hydraulics, electrical and air
driven motors. Both the wire rope hoist and chain hoist have been in common use
since the 1800s. however; Mass production of an electric hoist did not start until the
early 1900s and was first adapted by Germany. A hoist can be built as one integral-
package unit, designed for cost-effective purchasing and moderate use, or it can be
built as a built-up custom unit, designed for durability and performance. The built-up
hoist will be much more expensive, but will also be easier to repair and more
durable. Package units were once regarded as being designed for light to moderate
usage, but since the 60s this has changed. Built-up units are designed for heavy to
severe service, but over the years that market has decreased in size since the
advent of the more durable packaged hoist. A machine shop or fabricating shop will
use an integral-package hoist, while a Steel Mill or NASA would use a built-up unit to
meet durability, performance, and repairability requirements. NASA has also seen a
change in the use of package hoists. The NASA Astronaut training pool, for example,
utilizes cranes with packaged hoists.
Wire Rope Hoist or Chain Hoist
More commonly used hoist in today's worldwide market is an
electrically powered hoist. These are either the chain type or the wire rope
type.
Nowadays many hoists are package hoists, built as one unit in a single
housing, generally designed for ten-year life, but the life calculation is based
on an industry standard when calculating actual life. See the Hoists
Manufacturers Institute site[1] for true life calculation which is based on load
and hours used. In today's modern world for the North American market there
are a few governing bodies for the industry. The Overhead Alliance is a group
that represents Crane Manufacturers Association of America (CMAA),
Shanghai WANBO Hoisting Machinery (VANBON), Hoist Manufacturers
Institute (HMI), and Monorail Manufacturers Association (MMA). These
product counsels of the Material Handling Industry of America have joined
forces to create promotional materials to raise the awareness of the benefits
to overhead lifting. The members of this group are marketing representatives
of the member companies.
Common small portable hoists are of two main types, the chain
hoist or chain block and the wire rope or cable type. Chain hoists may have a
lever to actuate the hoist or have a loop of operating chain that one pulls
through the block (known traditionally as a chain fall) which then activates the
block to take up the main lifting chain.
A hand powered hoist with a ratchet wheel is known as a "ratchet lever
hoist" or, colloquially, a "come-along". The original hoist of this type was
developed by Abraham Maasdam of Deep Creek, Colorado about 1919, and
later commercialized by his son, Felber Maasdam, about 1946. It has been
copied by many manufacturers in recent decades. A similar heavy duty unit
with a combination chain and cable became available in 1935 that was used
by railroads, but lacked the success of the cable-only type units.
Ratchet lever hoists have the advantage that they can usually be
operated in any orientation, for pulling, lifting or binding. Chain block type
hoists are usually suitable only for vertical lifting.
For a given rated load wire rope is lighter in weight per unit length but
overall length is limited by the drum diameter that the cable must be wound
onto. The lift chain of a chain hoist is far larger than the liftwheel over which
chain may function. Therefore, a high-performance chain hoist may be of
significantly smaller physical size than a wire rope hoist rated at the same
working load.
Both systems fail over time through fatigue fractures if operated
repeatedly at loads more than a small percentage of their tensile breaking
strength. Hoists are often designed with internal clutches to limit operating
loads below this threshold. Within such limits wire rope rusts from the inside
outward while chain links are markedly reduced in cross section through wear
on the inner surfaces. Regular lubrication of both tensile systems is
recommended to reduce frequency of replacement. High speed lifting, greater
than about 60 feet per minute (18.3 m/min), requires wire rope wound on a
drum, because chain over a pocket wheel generates fatigue-inducing
resonance for long lifts.
The unloaded wire rope of small hand-powered hoists often exhibits a
snarled "set", making the use of a chain hoist in this application less
frustrating, but heavier. In addition, if the wire in a wire hoist fails, it can whip
and cause injury, while a chain will simply break.
"Chain hoist" also describes a hoist using a differential pulley system,
in which a compound pulley with two different radii and teeth engage an
endless chain, allowing the exerted force to be multiplied according to the
ratio of the radii.
Construction hoists
Also known as a Man-Lift, Buckhoist, temporary elevator, builder hoist,
passenger hoist or construction elevator, this type of hoist is commonly used on
large scale construction projects, such as high-rise buildings or major
hospitals. There are many other uses for the construction elevator. Many other
industries use the buckhoist for full-time operations, the purpose being to carry
personnel, materials, and equipment quickly between the ground and higher floors,
or between floors in the middle of a structure. There are three types: Utility to move
material, personnel to move personnel, and dual-rated, which can do both.[4]
The construction hoist is made up of either one or two cars (cages) which
travel vertically along stacked mast tower sections. The mast sections are attached
to the structure or building every 25 feet (7.62 m) for added stability. For precisely
controlled travel along the mast sections, modern construction hoists use a
motorized rack-and-pinion system that climbs the mast sections at various speeds.
While hoists have been predominantly produced in Europe and the United
States, China is emerging as a manufacturer of hoists to be used in Asia.
In the United States and abroad, General Contractors and various other
industrial markets rent or lease hoists for a specific projects. Rental or leasing
companies provide erection, dismantling, and repair services to their hoists to
provide General Contractors with turnkey services. Also, the rental and leasing
companies can provide parts and service for the elevators that are under contract.
Simple harmonic motion applications in engineering field
Vibration is a mechanical phenomenon whereby oscillations occur about
an equilibrium point. The oscillations may be periodic such as the motion of a
pendulum or random such as the movement of a tire on a gravel road.
Vibration is occasionally "desirable". For example the motion of a tuning fork,
the reed in a woodwind instrument or harmonica, or mobile phones or the cone of
a loudspeaker is desirable vibration, necessary for the correct functioning of the
various devices.
More often, vibration is undesirable, wasting energy and creating
unwanted sound – noise. For example, the vibrational motions of engines, electric
motors, or any mechanical device in operation are typically unwanted. Such
vibrations can be caused by imbalances in the rotating parts, uneven friction, the
meshing ofgear teeth, etc. Careful designs usually minimize unwanted vibrations.
The study of sound and vibration are closely related. Sound, or "pressure waves",
are generated by vibrating structures (e.g. vocal cords); these pressure waves can
also induce the vibration of structures (e.g. ear drum). Hence, when trying to reduce
noise it is often a problem in trying to reduce vibration.
Types of vibration
Free vibration occurs when a mechanical system is set off with an initial input and
then allowed to vibrate freely. Examples of this type of vibration are pulling a child
back on a swing and then letting go or hitting a tuning fork and letting it ring. The
mechanical system will then vibrate at one or more of its "natural frequency" and
damp down to zero.
Forced vibration is when a time-varying disturbance (load, displacement or velocity)
is applied to a mechanical system. The disturbance can be a periodic, steady-state
input, a transient input, or a random input. The periodic input can be a harmonic or a
non-harmonic disturbance. Examples of these types of vibration include a shaking
washing machine due to an imbalance, transportation vibration (caused by truck
engine, springs, road, etc.), or the vibration of a building during an earthquake. For
linear systems, the frequency of the steady-state vibration response resulting from
the application of a periodic, harmonic input is equal to the frequency of the applied
force or motion, with the response magnitude being dependent on the actual
mechanical system.
Pendulum
A pendulum is a weight suspended from a pivot so that it can swing freely.[1] When a
pendulum is displaced sideways from its restingequilibrium position, it is subject to
a restoring force due to gravity that will accelerate it back toward the equilibrium
position. When released, the restoring force combined with the pendulum's mass
causes it to oscillate about the equilibrium position, swinging back and forth. The
time for one complete cycle, a left swing and a right swing, is called the period. A
pendulum swings with a specific period which depends (mainly) on its length.
From its discovery around 1602 by Galileo Galilei the regular motion of pendulums
was used for timekeeping, and was the world's most accurate timekeeping
technology until the 1930s. Pendulums are used to regulate pendulum clocks, and
are used in scientific instruments such as accelerometers and seismometers.
Historically they were used as gravimeters to measure the acceleration of gravity in
geophysical surveys, and even as a standard of length. The word 'pendulum' is new
Latin, from the Latin pendulus, meaning 'hanging'.
The simple gravity pendulum is an idealized mathematical model of a
pendulum. This is a weight (or bob) on the end of a massless cord suspended from
a pivot, without friction. When given an initial push, it will swing back and forth at a
constant amplitude. Real pendulums are subject to friction and air drag, so the
amplitude of their swings declines.
Clock pendulums
Pendulum and anchor escapement from agrandfather clock
Pendulums in clocks (see example at right) are usually made of a weight
or bob (b) suspended by a rod of wood or metal (a).To reduce air resistance (which
accounts for most of the energy loss in clocks) the bob is traditionally a smooth disk
with a lens-shaped cross section, although in antique clocks it often had carvings or
decorations specific to the type of clock. In quality clocks the bob is made as heavy
as the suspension can support and the movement can drive, since this improves the
regulation of the clock (see Accuracy below). A common weight for seconds
pendulum bobs is 15 pounds. (6.8 kg). Instead of hanging from a pivot, clock
pendulums are usually supported by a short straight spring (d) of flexible metal
ribbon. This avoids the friction and 'play' caused by a pivot, and the slight bending
force of the spring merely adds to the pendulum's restoring force. A few precision
clocks have pivots of 'knife' blades resting on agate plates. The impulses to keep the
pendulum swinging are provided by an arm hanging behind the pendulum called
the crutch, (e), which ends in a fork, (f) whose prongs embrace the pendulum rod.
The crutch is pushed back and forth by the clock's escapement, (g,h).
Each time the pendulum swings through its centre position, it releases one tooth of
the escape wheel (g). The force of the clock's mainspring or a driving weight hanging
from a pulley, transmitted through the clock's gear train, causes the wheel to turn,
and a tooth presses against one of the pallets (h), giving the pendulum a short push.
The clock's wheels, geared to the escape wheel, move forward a fixed amount with
each pendulum swing, advancing the clock's hands at a steady rate.
The pendulum always has a means of adjusting the period, usually by an adjustment
nut (c) under the bob which moves it up or down on the rod. Moving the bob up
decreases the pendulum's length, causing the pendulum to swing faster and the
clock to gain time. Some precision clocks have a small auxiliary adjustment weight
on a threaded shaft on the bob, to allow finer adjustment. Some tower clocks and
precision clocks use a tray attached near to the midpoint of the pendulum rod, to
which small weights can be added or removed. This effectively shifts the centre of
oscillation and allows the rate to be adjusted without stopping the clock.
The pendulum must be suspended from a rigid support. During operation, any
elasticity will allow tiny imperceptible swaying motions of the support, which disturbs
the clock's period, resulting in error. Pendulum clocks should be attached firmly to a
sturdy wall.
The most common pendulum length in quality clocks, which is always used
in grandfather clocks, is the seconds pendulum, about 1 metre (39 inches) long.
In mantel clocks, half-second pendulums, 25 cm (10 in) long, or shorter, are used.
Only a few large tower clocks use longer pendulums, the 1.5 second pendulum,
2.25 m (7 ft) long, or occasionally the two-second pendulum, 4 m (13 ft) as is the
case of Big Ben.
Temperature compensation
The largest source of error in early pendulums was slight changes in length due to
thermal expansion and contraction of the pendulum rod with changes in ambient
temperature.[79] This was discovered when people noticed that pendulum clocks ran
slower in summer, by as much as a minute per week[56][80] (one of the first
was Godefroy Wendelin, as reported by Huygens in 1658).[81] Thermal expansion of
pendulum rods was first studied by Jean Picard in 1669.[82] A pendulum with a steel
rod will expand by about 11.3 parts per million (ppm) with each degree Celsius
increase, causing it to lose about 0.27 seconds per day for every degree Celsius
increase in temperature, or 9 seconds per day for a 33 °C (60 °F) change. Wood
rods expand less, losing only about 6 seconds per day for a 33 °C (60 °F) change,
which is why quality clocks often had wooden pendulum rods. However, care had to
be taken to reduce the possibility of errors due to changes in humidity.
Mercury pendulum
Mercury pendulum in Howard astronomical regulator clock, 1887
The first device to compensate for this error was the mercury pendulum, invented
by George Graham [57] in 1721.[8][80] The liquid metal mercury expands in volume with
temperature. In a mercury pendulum, the pendulum's weight (bob) is a container of
mercury. With a temperature rise, the pendulum rod gets longer, but the mercury
also expands and its surface level rises slightly in the container, moving its centre of
mass closer to the pendulum pivot. By using the correct height of mercury in the
container these two effects will cancel, leaving the pendulum's centre of mass, and
its period, unchanged with temperature. Its main disadvantage was that when the
temperature changed, the rod would come to the new temperature quickly but the
mass of mercury might take a day or two to reach the new temperature, causing the
rate to deviate during that time.To improve thermal accommodation several thin
containers were often used, made of metal. Mercury pendulums were the standard
used in precision regulator clocks into the 20th century.
Gridiron pendulum
Main article: Gridiron pendulum
The most widely used compensated pendulum was the gridiron pendulum, invented
in 1726 by John Harrison.[8][80][83] This consists of alternating rods of two different
metals, one with lower thermal expansion (CTE), steel, and one with higher thermal
expansion, zinc or brass. The rods are connected by a frame, as shown in the
drawing above, so that an increase in length of the zinc rods pushes the bob up,
shortening the pendulum. With a temperature increase, the low expansion steel rods
make the pendulum longer, while the high expansion zinc rods make it shorter. By
making the rods of the correct lengths, the greater expansion of the zinc cancels out
the expansion of the steel rods which have a greater combined length, and the
pendulum stays the same length with temperature.
Zinc-steel gridiron pendulums are made with 5 rods, but the thermal expansion of
brass is closer to steel, so brass-steel gridirons usually require 9 rods. Gridiron
pendulums adjust to temperature changes faster than mercury pendulums, but
scientists found that friction of the rods sliding in their holes in the frame caused
gridiron pendulums to adjust in a series of tiny jumps. In high precision clocks this
caused the clock's rate to change suddenly with each jump. Later it was found that
zinc is subject to creep. For these reasons mercury pendulums were used in the
highest precision clocks, but gridirons were used in quality regulator clocks. They
became so associated with quality that, to this day, many ordinary clock pendulums
have decorative 'fake' gridirons that don't actually have any temperature
compensation function.
Invar and fused quartz
Around 1900 low thermal expansion materials were developed which, when used as
pendulum rods, made elaborate temperature compensation unnecessary. These
were only used in a few of the highest precision clocks before the pendulum became
obsolete as a time standard. In 1896 Charles Edouard Guillaume invented
the nickel steel alloy Invar. This has a CTE of around 0.5 µin/(in·°F), resulting in
pendulum temperature errors over 71 °F of only 1.3 seconds per day, and this
residual error could be compensated to zero with a few centimeters of aluminium
under the pendulum bob (this can be seen in the Riefler clock image above). Invar
pendulums were first used in 1898 in the Riefler regulator clock which achieved
accuracy of 15 milliseconds per day. Suspension springs of Elinvar were used to
eliminate temperature variation of the spring's restoring force on the pendulum.
Later fused quartz was used which had even lower CTE. These materials are the
choice for modern high accuracy pendulums.
Atmospheric pressure
The effect of the surrounding air on a moving pendulum is complex and requires fluid
mechanics to calculate precisely, but for most purposes its influence on the period
can be accounted for by three effects:
By Archimedes' principle the effective weight of the bob is reduced by the
buoyancy of the air it displaces, while the mass (inertia) remains the same,
reducing the pendulum's acceleration during its swing and increasing the period.
This depends on the air pressure and the density of the pendulum, but not its
shape.
The pendulum carries an amount of air with it as it swings, and the mass of this
air increases the inertia of the pendulum, again reducing the acceleration and
increasing the period. This depends on both its density and shape.
Viscous air resistance slows the pendulum's velocity. This has a negligible effect
on the period, but dissipates energy, reducing the amplitude. This reduces the
pendulum's Q factor, requiring a stronger drive force from the clock's mechanism
to keep it moving, which causes increased disturbance to the period.
So increases in barometric pressure increase a pendulum's period slightly due to the
first two effects, by about 0.11 seconds per day per kilopascal (0.37 seconds per day
per inch of mercury or 0.015 seconds per day per torr). Researchers using
pendulums to measure the acceleration of gravity had to correct the period for the air
pressure at the altitude of measurement, computing the equivalent period of a
pendulum swinging in vacuum. A pendulum clock was first operated in a constant-
pressure tank by Friedrich Tiede in 1865 at the Berlin Observatory, and by 1900 the
highest precision clocks were mounted in tanks that were kept at a constant
pressure to eliminate changes in atmospheric pressure. Alternatively, in some a
small aneroid barometer mechanism attached to the pendulum compensated for this
effect.
Gravity
Pendulums are affected by changes in gravitational acceleration, which varies by as
much as 0.5% at different locations on Earth, so pendulum clocks have to be
recalibrated after a move. Even moving a pendulum clock to the top of a tall building
can cause it to lose measurable time from the reduction in gravity.
Friction application in mechanical component
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and
material elements sliding against each other. There are several types of friction:
Dry friction resists relative lateral motion of two solid surfaces in contact. Dry
friction is subdivided into static friction ("stiction") between non-moving surfaces,
and kinetic friction between moving surfaces.
Fluid friction describes the friction between layers within a viscous fluid that are
moving relative to each other.
Lubricated friction is a case of fluid friction where a fluid separates two solid
surfaces.
Skin friction is a component of drag, the force resisting the motion of a fluid
across the surface of a body.
Internal friction is the force resisting motion between the elements making up a
solid material while it undergoes deformation.
When surfaces in contact move relative to each other, the friction between the two
surfaces converts kinetic energy into heat. This property can have dramatic
consequences, as illustrated by the use of friction created by rubbing pieces of wood
together to start a fire. Kinetic energy is converted to heat whenever motion with
friction occurs, for example when a viscous fluid is stirred. Another important
consequence of many types of friction can be wear, which may lead to performance
degradation and/or damage to components. Friction is a component of the science
of tribology.
Friction is not itself a fundamental force but arises from fundamental electromagnetic
forces between the charged particles constituting the two contacting surfaces. The
complexity of these interactions makes the calculation of friction from first
principles impractical and necessitates the use of empirical methods for analysis and
the development of theory.
Friction is an important factor in many engineering disciplines.
Transportation
Rail adhesion refers to the grip wheels of a train have on the rails,
see Frictional contact mechanics.
Road slipperiness is an important design and safety factor for automobiles
Split friction is a particularly dangerous condition arising due to varying
friction on either side of a car.
Road texture affects the interaction of tires and the driving surface.
Measurement
A tribometer is an instrument that measures friction on a surface.
A profilograph is a device used to measure pavement surface roughness.
Household usage
Friction is used to ignite matchstick (Friction between the head of a matchstick
and the rubbing surface of the match box).
Balancing application in engineering field
Balance Engineering's complete line of production balancing machines utilize
various correction processing techniques to balance a wide array of customer-
specific parts and assemblies. We work closely with the customer to tailor the most
accurate, reliable and cost-effective balancing application to match your needs. From
simple drilling processes to more complex applications such as welding or punching,
Balance Engineering stands ready to help solve your balancing needs with any
number of standard and customized solutions.
Drilling Applications
This method of balancing customer-specific parts utilizes a drilling process to remove
metal for part correction. This process can be accomplished in a vertical or horizontal
attitude, and use any number of dfferent drill types and diameters. The appropriate
configuration will depend on specific part and production process requirements.
Typical parts utilizing this process include crankshafts, engine dampers, and other
rotating members with sufficient metal thickness to allow drilling without
compromising component integrity.
A newer technology used with great success on many of our machines is Minimum
Quantity Lubrication ('MQL') drilling. Rather than pumping large quantities of coolant
onto the part as necessary during a normal drilling operation, the MQL method
forces small quantities of coolant through the drilling tool and directly into the drill
hole during correction. This method allows faster drill speeds, resulting in shorter
cycle times and enhanced formation and extraction of drilling chips. The overall
drilling process is much cleaner. MQL has become the preferred method employed
by Balance Engineering on our machines using drilling correction.
Grinding Applications
Grinding is another commonly used method for balancing parts and assemblies. This
involves abrasive removal of material from specific areas on the part. This process
can be employed in either a vertical or horizontal attitude and use any number of
different grinding tooling, depending on the part configuration and correction
requirements. Typical parts utilizing grinding correction include flywheels, stators and
brake discs.
Milling Applications
This method of balancing customer-specific parts utilizes a milling process to remove
metal for part correction. Milling is generally employed for part configurations that do
not lend themselves to any other metal removal correction process. Typical parts
using this process include brake rotors, brake drums and stator assemblies, among
others.
Nibbling / Notching Applications
This method of balancing customer-specific parts utilizes a metal removal process
known as nibbling or notching. This involves using specialized tooling to shear small
sections of material from the part edge surface at calculated vectors to achieve
specified balance. Normally accomplished in a horizontal attitude, nibbling/notching
removes metal from the outside diameter of any given rotor in any number of
heights, widths or depths. Typical parts utilizing this correction process include
various transmission components such as hubs or housings.
Piercing / Punching Applications
This method of balancing customer-specific parts utilizes a metal removal process
known as piercing or punching. This involves using specialized tooling to remove
small sections of material from the part surface at pre-calculated vectors to achieve
specified balance. Piercing or punching can be accomplished in either a horizontal or
vertical attitude, employing any number of tooling shapes and sizes to extract
material from a given part. Typical parts utilizing this correction process
include thinner metal components such as flywheels, hubs or housings.
Welding Applications
This method of balancing customer-specific parts utilizes a metal addition process
known as welding. This involves using specialized tooling for attaching pre-cut or
variable length metal weights onto the part surface at pre-calculated vectors to
achieve specified balance. Weld correction can be accomplished in several different
ways, including projection and spot welding. Typical parts utilizing this correction
process include torque converters, turbine assemblies, axle/differential
assemblies and driveshafts, among others.
Current technology applied in belting system
Steel belts are top of the milk for Tetra Pak
Tetra Pak has recently launched the Tetra Evero Aseptic one–litre – the first aseptic
carton bottle for milk.
The new carton combines the easy handling and pouring of a bottle with the
environmental and cost advantages of a carton. It is initially being aimed at the
ambient white milk market, including non-oxygen sensitive enriched products,
including flavored milk and cream.
Unlike traditional carton materials, which are aseptically sterilized before they are
formed into shape, the Tetro Evero Aseptic is pre-formed and not flat-packed,
meaning it requires an alternative approach.
The majority of existing technologies for sterilizing performed shapes rely on a gas-
condensation process. This process involves the gas condensing on the material
surface, but this is known to be complex and difficult to control.
The Tetra Evero Aseptic, however, uses a new gas-phase sterilization technique
which involves the cartons passing through a unique aseptic chamber in pairs where
they are exposed to hydrogen peroxide. The gas comes into contact with the whole
preformed package – inside and out, removing any contaminants that might have
been present before entering the aseptic chamber.
The cartons travel on steel belts during this production process. The use of steel
belts is a highly hygienic alternative to using traditional plastic and PU conveyor
systems. Avoiding the spread of contaminants is imperative in belt technology: steel
belts are far easier to clean than their plastic counterparts and do not need to be
lubricated in order to transmit power. This is important because germs and
potentially harmful bacteria are attracted to dust generated by lubricant grease,
which can potentially contaminate food or other products.
Steel belts are not just available as flat conveyors, they can be customized in many
ways and offer novel and exciting solutions to a variety of complicated conveying
problems. Belts can be perforated with complex patterns for timing, vacuum or
dosing applications.
Together, the steel belt technology and the new gas-phase sterilization technique
used in the production of the new Tetra Evero Aseptic have resulted in a highly
effective means of commercial sterility – an innovative development which should
now set the gold standard for the production of aseptic packaging across Europe and
the rest of the world.
Stainless Steel Belts Shine in Solar Cell Applications
Belt Technologies, a leading provider of metal belt and conveyor systems, provides
photovoltaic manufacturers a more efficient means of producing solar cells that use
the sun’s energy to generate electricity. As the world makes significant moves
towards sustainability, manufacturers are continually searching for more efficient
ways to produce products that take advantage of renewable energy sources.
Belt Technologies’ steel belts have provided manufacturers a more effective solution
for transporting components through the cell manufacturing process as well as final
panel assembly. Used in tabber and stringer operations, the belts provide many
benefits not found in alternative belting materials. The belts’ robust nature allows
them to be perforated and sustain accuracy in high-speed vacuum systems. As a
result, cells can be moved precisely to the required welding spot to achieve
accuracies of .1mm or less in both the lateral and horizontal planes. Additionally,
stainless steel belts from Belt Technologies are able to resist the high temperatures
involved in laser soldering bus ribbons during the solar panel assembly process,
avoiding the quality-threatening belt degradation commonly seen with plastic and
fabric belts. Their longevity under intense heat provides cost savings to
manufacturers as a result of fewer belt changes and reduced down time. Abrasion-
resistant release coatings prevent solder buildup and provide protection for the
various fluxes commonly used in the manufacturing process.
Perforated Steel Belts Improve Efficiency in Blood Filter Production
Belt Technologies has developed a perforated stainless steel belt that has
significantly improved production efficiency for a leading manufacturer of advanced
technologies in the separation of liquids, solids, and gases. The belt, used to
transport pre-coated blood filter elements through a forced hot air drying chamber,
has streamlined the production process and helped Porous Media Corporation of St.
Paul, MN achieve machine efficiencies in the 96-98% range.
The belt’s large perforations allow for the maximum amount of airflow through an
upper and lower belt, resulting in complete drying of the liquid coating solution. Its
seamless non-stretch surface eliminates the threat of particulate debris being
introduced into the manufacturing environment, while allowing for a complete “clean
and place” process, which cannot be done effectively with other belting materials. A
cycled belt cleaning operation can be performed simultaneously with the production
of the filters, eliminating the need for stoppages and resulting in machine efficiencies
in the upper 90% range. The product’s non-stretch properties result in better
positioning and increased accuracy.
Independent Pulley System Steers Flat Belts for On-the-fly Adjustments
Belt Technologies has developed a simple and effective pulley system for
independently steering flat belts while allowing for easy on-the-fly tracking
adjustments. The patented system provides a solution to tracking problems
encountered as a result of operating environment changes and also eliminates
downtime by allowing independent belt adjustments on a multi-pulley common shaft.
Steering is accomplished by adjusting the angle of the pulley relative to the belt and
modifying lateral tension. Rather than moving the pulley shaft through the use of
pillow block adjustments, the ISP design fits a variable steering collar (with either a
skewed or offset bore) and a sealed bearing assembly to the body of the pulley.
When rotated, the collar changes the angle of the pulley body, resulting in the
controlled bi-directional movement of the belt across the pulley face.
New Stainless Steel Tapes Drive Robotic Arms
Belt Technologies has introduced a new high-performance line of stainless steel
drive tapes used in conjunction with SCARA robots in atmospheric and vacuum
wafer transport applications. The tapes provide significant advantages over
alternative drive methods including reduced vibration, improved accuracy, and a
cleaner manufacturing environment. Reinforced with standard or custom end tabs,
Belt Technologies drive tapes are easy to install.
The low-mass, low-stretch properties of these tapes result in precision tolerances
with no outgassing and low hysteresis. Smooth surfaces provide for a much cleaner
manufacturing environment by eliminating the particulate debris that is a common bi-
product of traditional systems. Designed to minimize vibration, these stainless steel
drive tapes allow for rapid acceleration, improved positioning accuracy, and high
levels of repeatability; resulting in better performance with increased throughput. Belt
Technologies stainless steel drive tapes can be customized for specific applications
in the nano-technology, solar and fuel cell, data storage, opto-electronics, LCD/LED,
pharmaceutical, and biotech industries.