Usually, when demanding rotary movements are required at high loads, energy chains with reverse bending radii are used. Typically, they allow circular movements of up to 540 degrees but they need deep and wide installation spaces.

The new system (shown above) allows rapid rotating movements of up to 3,000 degrees and depends only on the belt length or the height in the axis of rotation. The small masses involved mean that centrifugal forces are low, and that rotary speeds of up to 720 degrees per second are possible. The lightweight chains can be used horizontally or vertically.

The single-component, injection-moulded belt has chambers attached to it that are filled without needing to open or closed the chain links. Users simply press the lines into the chain from the outside. The chains can be used, for example, to accommodate servomotor, control, bus or fibre optic cables, as well as hoses routing fluids.

Applications are expected to include robotics and machines ranging from assembly equipment to amusement park rides. A further possible area of application is in wind power systems, where the turbine blades need to be controlled through a support which must be free to turn.

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The modular Twisterband system does not need to be customised to individual user specifications. One size is already available and larger and smaller versions are planned.

www.igus.de

An innovative application for pneumatics helps power a unique  vehicle. The Hydrogen Hybrid Bus (HHB), was built by Golden, CO-based Proterra with funding from the U.S. Federal Transit Administration (FTA) as part of the National Fuel Cell Bus Program, and is managed by the Center for Transportation and the Environment (CTE).

The HHB is operating  on existing bus routes through the Victoria, BC adding hilly, cold weather operations to the ongoing evaluation of the bus. The bus received significant positive exposure by operating throughout the Winter Olympic Games and was featured as part of a formal demonstration and media event on March 11, sponsored by the Southern Hydrogen & Fuel Cell Coalition (SHFCC).

The  bus is powered by lithium titanate batteries and two 16 kw hydrogen fuel cells, producing clean electric power in a lighter, quieter, and more aerodynamic design that is better suited for today’s transportation demands. The  only emission is water vapor. Although the bus was certified for use in the U.S., it successfully underwent additional testing and safety inspections in order to be driven in Canada. With more than twice the energy efficiency of other hybrid buses and four times that of conventional diesel buses, Proterra buses combine tremendous environmental benefits with substantial cost savings to the operator.

Hydrogen Hybrid Bus Details:

• The HHB is an electric hybrid bus that was purpose built for an electric drive train and can be configured with a wide variety of ‘engines’ or as battery electric only. This version uses clean fuel cells as the ‘engine’.
• The HHB carries 29 kilograms of hydrogen on board and can achieve up to a 480  km  range.
• The use of composite materials for the body makes it much lighter – and stronger – than conventional buses.
• Initial BC Transit evaluation has determined that the fuel economy for this bus in shadow service is approximately 70% better than typical  diesel buses.
• South Carolina and the University of South Carolina were selected as the primary site for the bus demonstration and evaluation because of their prominence in fuel cell and hydrogen research.
• The HHB meets Buy America Requirements while utilizing fuel cells provided by Hydrogenics (headquartered in Mississauga, Canada) representing a great US/Canadian partnership for technology development and job creation.

The Hydrogen Hybrid Bus was deployed in August 2009 and is engaged in a two-year demonstration and evaluation project to prove the feasibility of advanced hydrogen-fuel-cell technology applications for mass transit. The demonstration and evaluation project will be conducted in three cities; Columbia, SC, Austin, TX, and Victoria, B.C. Upon completion of the BC Transit demonstration, the bus will return to Columbia to continue its evaluation as part of the University of South Carolina shuttle fleet.

Seven thousand times a day, in four miles of tubing laced efficiently behind walls from basement to rooftop, a pneumatic tube system shuttles foot-long containers carrying everything from blood to medication. In a hospital the size of Stanford, where a quarter-mile’s distance might separate a tissue specimen from its destination lab, making good time means better medicine.

Stanford Hospital’s container transport system, which also serves the adjacent Lucile Packard Children’s Hospital, is one of the largest in the country. Its architecture is a sophisticated design of switching points, waiting areas, sending and receiving points. It hosts 124 stations (every nursing unit has its own); 141 transfer units, 99 inter-zone connectors and 29 blowers. To help alert employees to the arrival of containers, the system has more than three dozen different combinations of chiming tones.

Such pneumatic tube systems date back to the early 19^th century, where they drove the workings of postal services, department stores and other commercial businesses whose physical size demanded something faster than standard human pace. But those versions were designed to move paper, which could handle a hard landing. When computers began to eliminate paper with electronically deliverable data, tube systems lost their value until engineers figured out a way to control airflow to slow down the containers for a soft landing at their destination station.

At Stanford Hospital, before 1993, a team of about 20 people had the job of transporting the multitudes of tissue, medications and documents. However, the increasing size of the Hospital, and the addition of two adjacent buildings, the Blake Wilbur Cancer Center and the Lucile Packard Children’s Hospital, made the tube system option the most modern solution.

Depending on the diameter of a tube, cylinders can reach speeds of up to 25 feet per second, about 18 miles per hour, far faster than any human could ever manage.

It was also a question of best use of employee time, if, as often happened, a courier wasn’t available when a specimen needed to get to the lab. Having a nurse leave a patient’s bedside for a minutes-long run to the lab made no sense.

Reliable speed is crucial when the system carries blood products, some of which are temperature-sensitive and, by regulations, must be discarded if not properly maintained. The tube system, said Lab Operation Services manager Gay Routh, “is vital, very vital. I don’t know what we’d do without the tube system, especially when it comes to tests like those that happen in surgery. When arterial blood gases are sent from the operating room, we need to return results in a very short period of time, so physicians know if they need to change settings on a monitor. Years ago, before the tubes, we would get a phone call and we’d have to send somebody. It definitely slowed our turnaround time.”

The Hospital’s Chief Engineer Leander Robinson commands the system from a small basement office, where computer monitors light up every time someone puts a container in a shute, types in a numerical address and presses the ‘send’ button. The screen displays a tiny icon that reflects the container’s travel through various switches and transfers, but it moves so quickly it’s actually hard to track its passage. Even during the heaviest flow through the system, between noon and 2 p.m., a container can cover the longest start-to-finish distance ― 1,500 feet ― in less than three minutes.

The system has a complete set of checks and balances, sensing where containers are needed and sending them. Some departments, like the operating rooms, have dedicated lines that guarantee them a straight shot to the lab. “Blood products get first priority,” said Lee Chua, blood transfusion services manager.

The system does occasionally falter, but it’s operative 98.8 percent of the time, Robinson said. And no cylinder has ever gotten stuck in a tube, he said. He has software that monitors the system, charting its use station by station and watching especially those times when someone sends a cylinder “stat” ― the highest priority coding. It’s also a work in constant progress; the Hospital continues to evolve and locations can change. “The tube is everywhere,” Robinson said, “and the directories ever changing.”

The tube bending facility fabricates around three to four thousand parts per week, using tubing ranging from a few millimeters in diameter to over 100 mm. The materials used include titanium, aircraft-grade aluminum, and corrosion-resistant steels which are expensive. 

The company now uses a 65 mm diameter all-electric tube bender. The precision and repeatability of set-up with the servomotor-controlled architecture nearly eliminates scrap. The machine paid for itself in three months.

Bends are typically made to 1 mm 3D envelope accuracy – sometimes as tight as 0.3 mm.

The ductility characteristics of titanium, and in particular thin-wall titanium tubing, mean that slowing the bending process improves forming.

Servomotor control allows GKN to create bending programs that precisely control all aspects of the tooling’s speed and force, even at very low speeds.

The latest machinery installations are two combined left- and right-hand bending machines, which overcome a long-standing problem with specific component shapes. These include tubular parts with many closely spaced bends, and tubes with coil structures with the mechanical flexibility to accommodate flexing movement during the operation of wing flaps.

Work pieces can be transferred automatically from left to right hand tool heads as many times as required to bend the required shape in a single stage. Batch fabrication times have come down from three days to 1.5 hours for one of the coiled parts, and from 2.5 hours to just 30 minutes for a batch of the multi-bend part that involved switching machines.

Unison pioneered the concept of all-electric tube benders, and is the only UK manufacturer of this advanced type of forming machinery.  Unison tube bending machines are available in the US from Horn Machine Tools.

Unison Ltd.
www.unisonltd.com

::Design World::

IPT’s High Pressure Tubing is rated for use in temperatures from -100° to 600°F (-73° to 315°C), with maximum working pressure of 20,000 PSI (1030 bar) or 60,000 PSI (4140 bar). Tubing is supplied in 18-22 ft. lengths, with custom lengths available upon request.

This tubing is well suited for use in industrial applications where types AISI 304 and 304L provide insufficient corrosion resistance. Typical applications include heat exchangers, condensers, pipelines, cooling and heating coils, as well as applications in the offshore oil and gas, chemical, petrochemical, pulp and paper, and food industries.

Innovative Pressure Technologies

www.inpressure.com

::Design World::

Medium and high pressure products that are reviewed include needle valves, ball valves, check valves, double block and bleed valves, 2-, 3- and 5-way manifold valves, as well as fittings and adapters. Custom solutions and specialty products that are reviewed include banjo fittings, monel drip pots, fusible plugs, manifolds, fittings, double block and bleed valves, relief valves, ball valves and excess flow valves.

Innovative Pressure Technologies

www.inpressure.com

::Design World::

The PFA core tube is reinforced with a silicone layer bonded directly to the core and braid layer, using a process that removes the need for glues and avoids leachables. The braid layer is a 300 series stainless steel braid. Protecting the entire construction is a non-contaminating silicone cover. Temperature rating is -65 to 450°F (-53 to 230°C).

Swagelok Co.
www.swagelok.com

::Design World::

NITRA tubing is available in polyurethane and nylon styles, in inch and metric sizes from 5/32 inch or4mm up to1/2 inch or 12mm; tubing is available in 100 and 500-foot packages. Polyurethane tubing is available in black, blue and clear, and has a hardness specification of Shore A 98. The tubing offers superior kink resistance and is strong and flexible. Its tight outside diameter tolerance makes is ideal for use with NITRA push-to-connect fittings. Prices for polyurethane tubing start at $10.25 for 100 feet.

NITRA Nylon 12 tubing carries a hardness specification of Shore D 70. Nylon tubing is designed for applications requiring higher working pressures and better heat/chemical resistance. Available in black, blue and natural, this strong, yet lightweight tubing has a low moisture absorption rate so it will remain flexible with a longer life than other nylon tubing. Prices for nylon tubing start at $10 for 100 feet.

A variety of NITRA push-to-connect fittings are also available, including straight, elbow, tee and wye styles. Fitting bodies are made of a strong thermoplastic with stainless steel gripping claws, and are designed to withstand working pressures of -29.5” Hg to 150 psi and a working temperature range of 32° to 140°F. Threaded components are made of nickel-plated brass and have pre-applied Teflon thread sealant. The bodies of threaded elbow and tee fittings can be rotated after installation, allowing for variations in piping direction. Prices for fittings start at $4.00 for a five-pack.

NITRA pneumatic push-to-connect flow control valves are designed to provide accurate airflow regulation for precise motion control of pneumatic cylinders. The flow control bodies are made of strong thermoplastic and have stainless steel tube gripping claws and are available in meter-in, meter-out, and in-line configurations.

AutomationDirect

www.automationdirect.com/pneumatic-parts

::Design World::

The Huco Dynatork air motor is quite ingenious.  It is based on a unique free-floating piston design that is capable of precise position control.   Maximum torque is transmitted on start-up and this can be adjusted to fine limits by standard air-flow valves.  Unlike other makes that operate with a system of metal pistons and connecting rods, the Huco Dynatork motor is perfect for stop/start load speed applications under load.

Unlike its vane counterpart the Huco Dynatork air motor is also easier to seal.  It is therefore far more cost efficient as most of the energy stored up in the compressed air is converted into motion.  In fact it consumes up to 80% less air than a vane motor providing significant cost saving even at maximum torque.

This is an exceptionally clean motor available with non-lube air supply and in a corrosion resistant or acetyl housing.  It’s little wonder then that this economical and efficient product has attracted designers of food preparation and packaging systems.  However, it has to be said that until now its commercial potential has been somewhat impeded. 

When Huco acquired Dynatork, the company inherited a product that was highly effective but remained a first generation design.  It had some design issues that hindered its take-up in the hygiene conscious sectors. The recently launched generation two of the design corrects these.  The new Huco Dynatork air motor not only looks the technical product that it has always been but it is now ideal for a wider range of applications.

 On the original design pneumatic tubing was external to the housing.  This made it vulnerable, sensitive to temperature extremes and difficult to clean.  The pneumatic porting on the latest models is now an internal feature making them far more robust.  Fasteners are also recessed to reduce potential bug traps.

 Aluminium foil tray manufacturer Coppice Alupack has systematically replaced all its electric drives on rewind systems that handle the surplus foil after the aluminium coil has been stamped.  Inclusion of Huco Dynatork air motors has not only simplified the design but also made it more controllable and safer.  Their clean, non-lube running has also ensured hygienic production. The Huco Dynatork motors run from 0 – 220 rpm for 24 hours a day in a cycle that goes from stall to start in the order of sixty times per minute.

“The piston air motor has allowed us to adjust most of the tension out of the system to eliminate lacing breakage,” explained Engineering Manager, James Lamin.  “It has also made the process inherently safer by reducing torque and negating the need for any electrical cables.”  A further benefit is that maintenance of the motors can now be carried out by a shop-floor technician instead of a skilled electrician, saving cost and minimising downtime.

The suitability of the Huco Dynatork motor for stop/start applications under load has also been proven by Greydon Inc., the manufacturer of printing equipment for form, fill and seal packaging machinery. Its Bagaire taped bag loader ensure bags are presented quickly and in exactly the same position to the operator, time after time.  This accuracy makes the system ideal for the inclusion of inkjet coding.

The operating principle is simple but effective.  A leader tape is wound around two drive pulleys. When powered up, the system advances the bags by winding up the tape and pulling them up from underneath the load table.  The Huco Dynatork air motor is responsible for this operation and again provides a clean solution that is also suitable for wash down.

Thermobarb fittings offer:
• A lightweight, compact design
• Multiple barbs for secure connections
• Excellent chemical resistance
• Durability and high impact strength
• Styles including adapters, straight connectors, Y’s, tees, 4-way connectors, elbows, reducers, hose nipples, and more.

Each plastic material also provides specific features. Nylon resists physical stress and abrasion; polyethylene performs better at low temperatures than other plastics; PVDF handles higher temperatures and pressures well; polypropylene is solvent and chemical resistant. The
single-use Thermobarb is manufactured from FDA-approved polypropylene and meets USP Class VI and RoHS standards, is sterilizable by autoclave or gamma radiation, and is free of animal-derived ingredients.

Thermobarb fittings are designed to work with soft-walled tubing such as PVC, silicone, polyurethane, and TPR. Sizes range from 1/8 in. through 1 in. tubing I.D. for most styles; hose nipples from ½ in. through 4 in. tubing I.D. Pinch clamps and check valves are also available, as are brass Thermobarbs for more demanding applications. Push-to-connect fittings, compression fittings, cam operated couplings, and an assortment of clamps are stocked as well.

NewAge Industries, Inc.
www.newageindustries.com

::Design World::