GSM Power Transmissions UK Ltd sorts re-cycling picking station

Several geared motor units have been installed into a recycling plant in southern England in order to reduce down-time and improve efficiency. The plant has been converted from a hydraulic drive system with a very large power pack and complicated hose and valve system into a clean and simple electrified version with energy savings.

The plant has been operating for many years using hydraulic motors and gearboxes to perform the various individual applications which make up the picking station. The main application is the large in-cline conveyor where 2 hydraulic motors have been replaced with a highly efficient bevel helical shaft mounted gearbox and 15kw electric motor. The operators took advantage of this change and requested an increase in the speed of the conveyor by about 6% in order to improve productivity. The operator realised that with the increase in speed –the waste material was positioned more towards the middle of the belt –reducing the chance to tangle on the idlers, side skirts and head drum.

The in-cline conveyor is fed material from the "Walking Floor" Fines conveyor which when hydraulic was variable speed by varying the flow to a fixed displacement motor and gearbox. The customer was anxious to retain the variable speed function and so a shaft mounted planetary gearbox with mechanical variator and electric motor was supplied. This means that by a simple handle on the variator –the operator is able to adjust the feed of material onto the main incline conveyor whilst the conveyor is operational.

Tomas Healey –General Manager Comments: "GSM Power Transmissions UK Ltd were awarded the contract because of their hands on approach, attention to detail and willingness to understand the requirements of the plant and how it operated. There were a number of challenges on this project including having to design gearboxes which would retro-fit with little or no additional engineering and yet provide us with new parameters of operation to improve the productivity and efficiency of the plant. The support experienced was excellent and commissioning was completed in phases which caused no down-time thanks to the new solutions mounting straight in to place of the original units, an essential requirement due to the continuous nature of this kind of industry."

Once the material has dropped from the incline conveyor onto the shaker plate –the material starts to be sorted. Lumps of rubble ,stones and buliding aggregate fall through onto a second Fines conveyor which was also converted from Hydraulic to electric drive. The use of shaft mounted planetary gearboxes and electric motors are ideally suited to this type of application because they are robust in design, highly efficient and compact so that they can be squeezed in to tight spaces with relative ease. The weight of the shaft mounted planetary gearbox together with the transmittable torque is also a big advantage especially when shaft mounting from an existing driven shaft.

The trommel which separates the aggregate by size was being driven by 2 hydraulic motors. These have been replaced by 2 electric motors and gearboxes. The Planetary gearbox option was chosen because on the Trommel they are suitable for high radial loads exerted onto the output's twin taper roller bearings which support the output shaft .The space available to fit the drives was also very limited and the plant runs 24/7 so reliability was also paramount in the decision of what type of drive to install. The planetary gearbox affords a highly efficient compact gear design which transmits torque from the sun-pinion to the planet gears all encased within a planet ring -this allows ratios on a single stage from 3:1 to 7:1 and as the planetary gearbox is a modular design –ratios up to 20,000:1 are not un-common.

Jon Snaith –Managing Director of GSM Power Transmissions UK Ltd comments " this was a particularly enjoyable and rewarding project to work on because there was so much variation in the requirements of the drives. The Industrial Planetary Gearbox range from GSM PT UK LTD has a large torque range available from 1,000Nm to 170,000Nm and incorporating innovative casing and output configurations like foot mounted, flange mounted , in-line or right-angle and the unique options for shaft mounted gearboxes like the shrink disc version and female keyed shaft version- where the cost of splining the driven shaft is illuminated from the decision making process.

High radial load capacity versions of each gearbox torque size are manufactured for applications like winches and slew drives - so that the OEM manufacturer gets a competitive and compact solution to work with.

Jon Snaith adds "We have 3 versions of right-angle planetary – the conventional planetary gears with spiral bevel, planetary gears with bevel helical and planetary gears with a worm/wheel input. All these options allow the best selection for the application to be carried out and give the OEM customer complete peace of mind".

GSM Power Transmissions UK LTD provides electric and hydraulic drive solutions for all kinds of applications like access platforms, off-shore spooler/winch systems, material handling, crushers and mixers etc.