Mechanical Technology May 2016

⎪ Products and services ⎪

Failsafe brake puts a stop to ‘run-aways’

Compact vortex flowmeter for low viscosity liquids KOBOLD Instrumentation, represented in South Africa by Instrotech – a Comtest Group com- pany, has introduced the compact, cost-effective vortex flowmeter Model DVZ, used for measuring and monitoring smaller and medium-sized flow of low viscosity, water-like liquids in pipes.  This device has impressed in numerous series applications due to its reliability and response time. It functions without any me- chanical moving parts, using the vortex prin- ciple, where a sharp-edged object, the Karman vortex-generator, is installed within the flow duct, making it virtually maintenance-free. This is a considerable advantage over devices based on the variable area or impeller principle. Vortices are created behind the object whose frequency is proportional to the velocity of flow of the liquid. The flow volume can be determined with a high degree of accuracy by measuring the vortex frequency. The result is a very high linearity over the whole measuring range (0.5- 4.5 or 10-100 ℓ /min) with an accuracy of +2.5% of full scale. Unlike calorimetric flow measurement, its measuring principle works irrespective of the temperature and without time delay and can thus the instrument can also be used in time- critical applications. The measurement process is suitable for practically all liquids with a viscosity similar to water – irrespective of the pressure, temperature, density and electrical conductivity of the medium. Due to its specific operating principle, Kobold’s DVZ flowmeter is especially suitable for measuring aggressive, corrosive or saline solutions. It can also be used for ultrapure media. www.instrotech.co.za

Bobcat Equipment South Africa, in partnership with Ferrobrake in Wit- bank, has pioneered a failsafe braking system on the Bobcat T40180 Telescopic Handler that optimises worker safety during materials handling operations in surface and underground mining by stopping the machine in the event of engine failure.

Bobcat Equipment’s failsafe brake system passed rigorous independent tests.

“The brake system is a critical compo- nent on any piece of moving machinery and in South Africa it is a mine safety requirement,” says Bobcat engineer, Ian Caulfield. “Reducing the risk of run-away machines, especially in underground mining where machines are taken down steep incline shafts of up to 25°, cannot be over-emphasised. “We took the decision to design the brake system for Bobcat’s largest tele- scopic handler, the T40180 18 m high- reach machine, as it already delivers the best possible efficiency and productivity through class-leading performance, while always focusing on safe operation thanks to the machine’s state-of-the-art safety systems. “The failsafe brake system is in line with mine safety regulations and is pri- marily designed around engine failure,” explains Caulfield. “Brakes are applied hydraulically and if the engine cuts out, the lack of hydraulic oil flow allows the

the magnetic steel handling industries by storm. The technology uses two diametri- cally polarised magnets, one rotating on top of the other. When the top magnet is rotated by 180° relative to the bottom, the magnetic poles of both magnets align to generate a powerful magnetic field. When rotated back 180° to be counter- aligned, the magnetic field within the magnet material collapses. This creates a permanent magnet that can be turned on and off at will. While magnets have been used for welding, fabrication and general industry for a long time, their role has been limited as they are often considered a hassle. Magswitch changes that! The days of wrestling with magnets – to place them accurately, release them and clean them, for example – are forever over. Magswitch brakes to be automatically spring ap- plied. In the event of engine failure while the machine is still moving, the failsafe brake system will automatically apply the brakes, bringing the machine to a stop. “Once the system has stopped the machine, brakes can be released me- chanically or porta-power can be used.” The tamper proof system also incorpo- rates an emergency brake, which can be activated by simply pushing an emergency stop button. Caulfield adds that the system is also available as an after-market fitment. “We have signed an exclusivity agreement with Ferrobrake with whom we worked very closely throughout the design and engineering stages,” contin- ues Caulfield. In conclusion, he reveals that there are plans in the pipeline to develop a similar failsafe brake system for the Bobcat TL470 telescopic loader. www.bobcatsa.co.za

Magnet technology: changing steel handling

Magswitch, an industry leader in ad- vanced permanent magnet technology, has patented technology that is taken

challenges traditional and time consum- ing clamping practices on small and big jobs, leading to time savings, faster set ups, convenience and safety advantages. From the point steel is received to how it is moved through the plant and fabricated, Magswitch tools can be ap- plied to improve safety and productivity. www.vermontsales.co.za

The Magswitch 600 A switchable magnetic welding clamp can simply be placed on a clean work surface, flat or round, and turned on, making welding set-up quicker and easier than ever.

Mechanical Technology — May 2016

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