Driving a bargain

Over the last year, the power transmission industry has been innovating right across the sector. From power chain technology to minimising the number of components within a system and creating methods of managing power quality, companies have been improving their existing technologies.

'The major trend at the moment is integration,' said Glen Phillips, customer services manager at

. 'By integrating several items to create a drive system it reduces the number of components needed.

'Whereas once you would have a motor, a feedback or measurement system a controller and a driver, now these are being integrated into one or two products — such as having the drives, controllers and motors as a single unit. As well as the simplicity, this also saves both money and space.'

Contamination of some products by oils and lubricants may cost manufacturers thousands of pounds, meaning that finding ways to dispense with them is also vital.

'There are some applications where lubricants are difficult or unwanted — for example, managing with a heavily lubricated chain in a hygiene sensitive environment such as the food industry is not good,' said David Turner, marketing communications manager for

. 'So within our Syno range, we have developed chains that either have their own internal lubrication or do not need it at all.'

A recent addition to the range is the company's Syno polymer bush product. This has a polymer component, meaning that the metal rubs against specially-designed plastic rather than another metal component, dispensing with the need for lubricants.

'The product is available in large sizes so is particularly suitable for outdoor and heavy-duty applications,' said Turner. 'It has been used in waste reprocessing plants and car assembly lines. An additional benefit is that the lack of lubrication makes it environmentally friendly.'

Renold has also developed the Smartlink, which is about to be widely launched. 'The product allows engineers to find out details about the loads that are being experienced by chains in normal use,' said Turner. 'The device, which consists of strain gauges, electronics and a battery, is attached to plates on one side of the chain.

'As it travels, data concerning the loads, shocks and so on is collected and recorded by a microprocessor. It can warn if damage is about to occur, or if the chain is in danger of breaking.'

The data showing strain can also be downloaded for analysis, allowing engineers to fine-tune equipment to optimise performance, or isolate problems to prevent chain wear.

Some systems are not only preventing wear and damage, but are also saving energy — which is extremely important as high fuel prices continue to affect profits. Switching to variable speed drive technology is helping manufacturers improve both their production and energy efficiency, saving users money.

Three aluminium extrusion presses at Alcoa near Hanover, used to produce medium and high strength alloys primarily for the aerospace and automotive markets, have installed variable speed drives from

of Powys. The systems have cut energy consumption by 40 per cent, saving thousands of kilowatt hours of energy every year.

Alcoa's original hydraulic plant was designed to provide the required thrust with additional oil being sent through a by-pass, meaning that the pumps were effectively running at full speed all the time. However, Control Techniques' variable speed drives integrate with the hydraulic controller using Profibus, giving exactly the required power at every stage of the operation.

As well as saving power the system provides better control, giving improved quality of extrusions. And lowering stress on the equipment means production is less susceptible to breakdown.

The environmental theme of power transmission innovation continues with the recent launch of new generation of synchronous belts by drive belt specialist,

. The company's Poly Chain GT Carbon system is designed to offer an increased power rating through the use of carbon tensile cords. The technology replaces roller chains or gearboxes, creating a flexible and lightweight synchronous drive with carbon tensile cords that provide substantial energy savings. Conventional Poly Chain belts use aramid fibre cords to provide the necessary tensile strength and flexibility.

The new product, however, features a highly fatigue-resisting tensile cord in the belt, made from a new carbon fibre polyurethane compound already used in the aviation industry. This carbon cord guarantees the transmission of high power in a very small space. Reverse bending strength is also good, and impact resistance is claimed to be a improvement over aramid.

As the stretch of the belt is virtually zero, tensioning remains constant during the whole service life, provided drive installation is correct. The high power density also allows for the use of narrower belts.

Gates says the power density of Poly Chain GT Carbon is better than that of conventional roller chains and reaches the level of gearboxes. This means that the new belt drive can replace much more complex types of drive systems.

Meanwhile, there have been improvements in the technology used to ensure the consistency of power quality.

recently launched a next-generation version of its Dynacomp dynamic response compensator. This provides reactive power compensation to solve a variety of industrial network power quality problems associated with fast variable loads.

The Dynacomp acts as an ultra-rapid, transient-free capacitor bank, with the reactive power step switching performed by thyristor modules instead of traditional contactors. Consisting of static switches and advanced controllers, it offers benefits including ultra-rapid power factor compensation, reduced voltage drop and flicker and transient-free switching.

There are also a very high number of switching operations, and both three-phase and single-phase versions are available as part of a range from a few hundred kvar up to several Mvar. The devices can also partially filter harmonic currents, thereby reducing total harmonic distortion and improving the network power quality.

Given the diversity of new products now available, those making use of power transmission technology are in a position to benefit greatly from both smoother production and fewer breakdowns.

Not only this, but with some systems offering power efficiency savings and the ability to dispense with lubricants, companies using them will also find their competitiveness will receive a significant boost.