NEWS & REVIEWS
Working closely with RMC Surfacing which operates a large fleet of Scarab`s single-engined sweepers, Scarab has designed its latest machine for the highways contractor. The brief was for a high-production machine capable not only of non-stop work behind the planer but also washing the surface when required, often within a 12 hour road closure.
Scarab of course pioneered the single-engine sweeper which uses the vehicle engine to power its suction fan and brushes via a hydraulic drive. The abscence of the auxiliary engine, its fuel tank and cooling system used on most sweepers means more than one tonne more payload and a bigger hopper, a great advantage when working in isolated locations because the water tank can be made bigger.
The advantages of having only one engine to fuel and service are obvious, but until Scarab came along some 20 years ago the problem had been how to keep the lorry engine running at sufficient rpm to power the suction fan and brushes, while keeping road speed down when moving - yet still retaining normal travel speeds.
The solution was twofold. First came the remarkable increase in engine power outputs, so a relatively small truck had the 50 to 60 Bhp in reserve to power the sweeping services as well as moving along the road. The second development was hydrostatic drive, achieved by fitting a hydraulic pump to the engine and a motor on the drive shaft. While sweeping the Scarab becomes an automatic, with forward-reverse shuttle lever and speed from 0-30km/h controlled by the accelerator. The vehicle will climb a 20% gradient fully laden. For travel, the hydrostatic drive is disengaged and the vehicle driven in a normal manner.
One might expect a cost advantage from using red diesel in the auxiliary engine rather than the all too expensive white required by the motive power. But because the Scarab has only one engine working in its most efficient torque band it uses less fuel than a twin-engined sweeper with one idling and its auxiliary working hard, doubling friction and thermal losses. In fact the Scarab uses as much as one-third less, according to tests carried out by the Paris municipality. Noise and exhaust emissions are also reduced, a point recognised by environmentally conscious New Zealand which has a favourable rate of Import tax for the Single-engine Scarab.
Scarab Sweepers have large diameter trunking to give a direct path from nozzle to the 900mm diameter suction fan on the roof of the hopper, giving maximum efficiency. On the Magnum Plus the fan speed is raised by 15% to 2300 rpm, while a boost switch gives upto 30% more power for difficult locations. A seperate hydraulic pump on the vehicle PTO powers the wash water pump fitted under the hopper, providing an impressive 60 litres per minute at 250 bar. Scarab has considered recycling the wash water from the hopper, but concluded that such washings would be too heavily contaminated.
Another recent improvement is CANbus, or computer area networking, a system which Scarab has developed itself. Older Scarabs had scores of wires leaving the control console, the new machines have only a few pairs between a series of mini-computers around the vehicle. Wiring is greatly simplified with one loom now fitting all the machines, updates and additions are easy, and the diagnostic system tells the fitter all he needs to know as well as monitoring every component in operation.
The demonstrator which McCreath Taylor has been taking aound the province last month is on a Mercedes Benz Atego chassis, though products of most manufacturers are also suitable. The Atego cab is roomy even with the central console for the sweeping gear. I have always liked Merc interior design, which may appear dull to some. After a long day, however, it`s still restful on the eye. The seats are equally restful on the other end, although they seem firm at first.
The deep windscreen and tapered side windows give an excellent view to the front, but the sleeper cab on the demonstrator has a nasty blind spot to the offside rear quarter, this being a left hand-drive vehicle. So it`s necessary to pull up square to a junction when turning left, and inevitably a car comes up the inside of the sweeper. Northern Ireland operators seldom need to sleep out on remote motorway jobs, so I would choose a day cab with rear windows for the extra rearward view so important to the brush driver.
Driving the Atego is easy, it`s as light as a feather and it`s tight turning circle makes it amazingly handy for street work, never mind an 18 tonner.
To sweep, simply press the clutch, select top gear, switch on the hydrostatic drive and the fan from the central console, switch on which ever brushes you need, and press the accelerator.
All modern trucks are quiet, but the Atego chassis seems well matched to the Scarab in the that noise levels are exceptionally low. The Merc engine whispers away at only 1200 rpm when working, its 230 horses being ample to provide propulsion, water pump at full pressure and all sweeping services at the same time.
Such quiet operation is a real boon. An auxiliary engine produces more noise particuarly for the driver, which I find very tiring whether it`s a sweeper or a fridge rumbling away behind my head. The relatively low fan speed is also a big help, for the public is becoming less tolerant of noisy machinery.
The front wash bar and the trailing nozzles are optional extras. British cities have yet to adopt street washing but the Magnum Plus is the machine to do it. The front jets strip the muck away, the rear nozzles leave a damp rather than a wet surface.
The huge water tank could be reduced in size and the hopper brought forwards to shorten the vehicle. However such is the capacity that RMC finds it useful for topping up roller water tanks on site, always a problem in isolated areas.
Greatly Impressed I asked Scarab`s Vic Beckwith if he thought sweepers would become even bigger. "I think the Magnum Plus is probably the limit, because a bigger machine would be too clumsy. Nobody has asked us for three axles, which would increase the cost considerably. Our single-engine design gives us a better payload than anyone else, while on the continent we can go to 19 tonnes with an 8.5 metre hopper.
"We think the greatly increased water tankage is the significant development, and makes for a very efficient machine. As a company we can tailor machines for different applications, adjusting tank and hopper size to suit and with a wide choice of water systems. Whatever the customer wants we`ll build it"
Marketed by 3D in France, under the Scarab name in the UK and by BOMAG on other markets, where it is known as the FS6000, this machine is designed for worldwide use. The machine comes with a sophisticated CANbus control system that passes control instructions for sweeping functions through an ergonomically-designed panel. The system features self-diagnostics as well as a range of sweeping data acquisition functions, to monitor condition and performance and help identify any maintenance issues early on.
The waste tank features a 6.35m3 capacity and is made from stainless steel, for corrosion and abrasion resistance. The water pump has a suction filter and is powered by a hydraulic motor that supplies water to the brushes and suction nozzle. Four water jets are fitted to the nozzle at 90° intervals and provide a dust-suppressing spray, while the water tank has a 1,250litre capacity. The suction inlet tubes have automatic separator flaps and there is a 1.5m² suction filter screen that tips for cleaning. Bulky waste can be stored in two large compartments on either side of the tank.
The all-steel, 250mm diameter suction nozzle is fully adjustable, while the 400mm diameter wide sweeping brush and 650mm diameter side brush are powered by direct-drive hydraulic motors. The pneumatic system is supplied by the auxiliary air intake on the chassis and is equipped with a pressure regulator and a filter/water separator.
As you may already be aware the previous UK distributor for Mathieu went into administration some time ago, and since July, Scarab Sweepers have been distributing Spares and Servicing for the Mathieu product in the UK.
We are very pleased to confirm that Scarab Sweepers have now been appointed as the sole UK distributor for the Mathieu product range from November 2008.
Commented Mark, “The Scarab vehicles that we have in our fleet are essential to us performing our street cleansing duties in Fenland. They complement the work completed by compact and pavement sweepers, covering many tens of thousands of miles each year.”
“ Fenland District Council has its own, four bay, well equipped workshop facility staffed by 7 fully skilled apprentice trained technicians. The work load is varied with cars, vans, trucks, tankers and refuse vehicles to look after.” Mark Gregory proudly boasts of the range of work undertaken by the workshop and its ethos of walking towards any challenge thrown upon it.”
“The technicians are keen to keep up with the advances of modern vehicle technology. A training plan maps the training needs of the staff to prepare them for the challenge of keeping trucks where they belong, on the road performing their duties. Staff have attended the Scarab training centre to learn in detail the maintenance, repair and fault finding diagnostics of the Scarab chassis mounted sweeper. Future plans are to receive training on the latest CANbus system as fitted to the latest Scarab acquisition.”
“The principal of good regular and effective preventative maintenance has clearly paid off. The Scarab “3000” sweeper on a DAF 45 series chassis is now 13 years old and in daily use. Under normal circumstances a vehicle would not be kept on the fleet for such a long period of time. However there is always a case for judging each case on its merits and without question this vehicle has proved to be an asset worth looking after.”
The issues in Fenland might well be unique. Although many rural local authorities have to respond to the effects of agriculture on the highway, in Fenland with its particular soil quality, and very open nature, blown topsoil and the effects of agricultural activities, such as sugar beet harvest and transport, means that frequency of sweeping has to be such that operatives are always on top of these issues. As a result Fenland aim to sweep all kerbed roads at least every four weeks, with many on a daily or weekly pattern, dependant upon need and location.
“The new Scarab Merlin sweeper with its larger capacity (over 6000kgs) will help to improve even further the efficiency in sweeping the rural villages at the required frequency to achieve Fenlands targets for the cleansing Best Value indicator BVPI 199”. commented Mark Mathews, Environmental Services Manager, adding “ Fenland is proud of the improvements made through its “Streets Ahead” programme over the past three years that has seen substantial investment in cleansing, street sweeping and “Fly tipping” removal. The best value indicator BVPI 199, which is a measure of street sweeping and street cleansing, has improved from 24% below standard to 9% within these three years. This is without doubt due to the ability of Fenlands sweeping fleet and their drivers to keep on top of their work during all but the most difficult times of year. This effort is complemented by other cleansing staff who are committed to delivering a high standard. This commitment has also been equally matched by the Council in providing staff with their preferred options when it comes to the best possible tools to get the job done.”
Manchester United Football Club (MUFC) has a new sweeper, but this particular new signing will never kick a ball. Instead, two brand new Scarab sweepers supplied to Trafford Council by TransLinc will keep the Old Trafford Stadium spick and span.
As experts in supplying highly tailored local authority vehicles, TransLinc has provided Trafford Council with a fleet of 14 road sweepers. Two Scarab units have made the grade, one in full Manchester United livery, to keep the Old Trafford area clean on match days.
The stadium has specific operational requirements and TransLinc was tasked to source units capable of cleaning around and under the stadium, as well as the car park and streets in the surrounding area. The Scarab Merlin XP 7.5 tonne street sweeper was the obvious choice to keep the streets around Old Trafford clean, while the Scarab Minor Compact Urban/Precinct ticked all the right boxes for cleaning around the stadium, thanks to its vast array of specialist equipment.
Equipped with a unique sweeping brush configuration, a powerful four metre long wander hose, high pressure water jet and side access doors for the loading of bulky waste items, the versatile sweeper will ably cope with the specialised heavy duty cleaning requirements of one of the UK’s foremost sporting venues.
The sweeper is an essential part of the Manchester United team, making an appearance at every home game. It is in operation for up to four hours during each match, clearing up debris left by the 78,000 spectators visiting the ground. On average the unit will clear five tonnes of rubbish on each outing.
George Johnstone, Group Property Manager of Manchester United says, “It’s our responsibility to ensure the Stadium and its surroundings are a safe and welcoming environment for our staff, players, supporters and visitors. This includes removing any dirt or debris that could be a potential health or safety hazard. We are grateful to Trafford Council and TransLinc for providing us with machines that perform this task thoroughly and efficiently.”
TransLinc’s Regional Sales Manager, Rob Hobson said, “Due to Manchester United’s specific cleaning requirements, TransLinc was tasked, by Trafford Council, to source units capable of covering all eventualities both inside and outside the stadium. Working closely with suppliers such as Scarab ensures we have the correct vehicle on hand to meet these needs.”
Vic Beckwith, Sales and Marketing Manager, Scarab said, “We were well aware that a venue like Old Trafford Stadium requires different cleaning approaches for individual areas. The Scarab Merlin XP sweeper was perfect for sweeping the streets around the stadium and the Scarab Minor sweeper was chosen because it copes with varied cleaning in more confined areas, like the seated stands.”
Having an auxiliary, or donkey, engine means that the sweeper brush is run on reduced-tax red diesel, with just the truck chassis being moved by expensive DERV.
Yet there are those who would say that running the hydraulics from the truck`s own engine does not add as much to fuel consumption as the second engine will use. As an environmental aside, there also seems little point in specifying the latest Euro 4 engine in the chassis, if the secondary engine does not have to conform to that standard as well.
But there remains demand for both systems, as evidenced by the fact that even Scarab - a long time supporter of the single engine truck - now offers a twin-engined sweeper to those who want one, although that is primarily for overseas markets. Scarab`s main interest remains in the single-engine market, with the Merlin XP its latest 7.5 tonne model. The Merlin XP has been designed specifically for the requirements of the Euro 4 trucks on which it will be built. And LAWR caught up with one working for the London Borough of Sutton, to the south of the capital.
As mentioned, the Merlin XP was designed around Euro 4 chassis requirements, taking into account the additional weight that they will carry to cope with achieving emissions regulations. This includes AdBlue tanks and other added technology that can result in a weight rise of up to 60-100kg over Euro 3 models of the same truck. While this sort of weight increase can be largely ignored on a heavier model, on a weight conscious 7.5 tonne vehicle it becomes an important consideration.
MAKING LIGHT WORK OF THE DESIGN
To combat this, Scarab`s designers and engineers went back to the drawing board and created a body that is up to 300kg lighter than its previous 7.5 tonne sweeper, offering at least 550kg more payload than some competitors. The XP in the title means just that: eXtra Payload. On an Iveco or Daf 7.5 tonne chassis, Scarab claims that the Merlin XP with a single sweeper has a a potential payload of 2,325kg, while the more popular dual sweep truck can carry 2,115kg.
This weight cut has been achieved by reducing the height of the body, the resulting loss of metal making up the bulk of the weight saving. But the truck retains a competitive 900 litre water tank at the front of the body and the hopper has a healthy 5.5m3 gross capacity, down from 6.2m3. That means a hopper payload volume of 4.7m3, which is certainly competitive against a twin-engined truck.
As with all of the Scarab`s Merlin trucks, the XP uses the firms proven hydrostatic drivetrain, which is fitted in the chassis between the regular truck gearbox and the back axle. This transmission design allows the sweeper to be driven to the work site as a conventional truck, with all of the fuel consumption benefits of the latest Euro 4 designs. When ready to sweep, the driver simply engages top gear in the regular gearbox and switches on the hydrostatic transmission.
In hydrostatic mode, the operator controls forward and reverse direction by the use of a simple lever next to the driver`s door, which is perfect for those who prefer to sweep with a head out of the window.
The truck`s throttle pesal determines the travel speed. At the same time, the gearbox drives the hydrostatic pumps to power the suction fan and brush system, providing protection from abuse for both the truck`s driveline and the sweeper attachment.
The hydrostatic transmission provides travel speeds of 0-20mph and Scarab claims that the truck can tackle the steepest of gradients without losing power to the sweeper or suction operation. That suction system uses a 900mm diameter fan mounted in the top of the hopper, providing a virtually straight through flow of air from the suction nozzles.
The nozzles themselves are 750mm wide with a 250mm diameter suction hose. Four manually adjustable water spray jets are fitted to the nozzles at 90° intervals to provide internal dust supression. An optional four-jet water boost bar can also be fitted in front of the suction hose for use in extreme conditions. The central wide sweep brush is a 320mm diameter design with direct hydrostatic drive. The brush is fully floating with shock absorbers to prevent bounce. Three-speed control is standard and customers can add a brush pressure control if desired.
The suction nozzle, side brush and wide sweep brush can be raised or lowered independently . This provides a variety of sweeping options: from a 740mm wide suction nozzle only;through a 1,060mm suction nozzle and side brush; a 2,000mm wide suction nozzle, side brush and widesweep; or the full 2,950mm width using both nozzles, both side brushes and the wide sweep central brush.
The Merlin XP also comes with a lightweight 4m long wander hose with a 150mm diameter nozzle, for cleaning gullies and akward areas. Quick release wander hose points are located on either side of the body`s rear door. All of Scarab`s sweeping and suction systems are controlled by a sturdy CANbus panel in the cab.
The panel controls the suction, fan, brushes, hopper, work lights and water sprays. However there is a secondary set of controls on the chassis for tipping the hopper, allowing closer inspection of the tipping area for drivers. The CANbus panel also displays operating data, including fan speeds, distance and hours swept information, and can be used for system diagnosis in the event of a fault.
The Scarab Merlin XP successfully answers all the questions asked by the latest emissions legislation. With chassis becoming heavier, to cope with with AdBlue tanks and other exhaust after treatment, Scarab has managed to reduce the weight of its sweeper equipment to keep payload for the operator high. Certainly there has been a reduction in the hopper volume, but this has been more than offset by the payload advantage, and the truck will be able to work for a lot longer with the slightly smaller hopper than it would with virtually no payload capability.
As Euro 4 trucks become the norm, an increasing number of local authorities and contractors are going to be looking to maximise the use of their vehicles. If they decide to stay at 7.5 tonnes , Scarab`s Merlin XP offers a solution to meet their needs.
Dan Gilkes is a freelance road tester.
Merlin is Man Enough for Sutton
The London Borough of Sutton runs four Scarab Merlin XP sweepers in a long term contract hire agreement with vehicle specialist London Hire. London Hire`s contract rental agreement covers all of the Borough`s vehicle needs, except refuse collection vehicles. The five year rolling contract, which began 18 months ago, replaced around 70 cars, mini buses, light commercial vehicles and sweeper trucks that were either owned by, or leased by the Borough.
In a co-operative twist, London Hire sub-contracts the maintenance of the vehicles back to the borough`s garages. In the case of the sweepers, that only covers the chassis because Scarab has a seperate maintenance agreement with the borough for the brush equipment.
Sutton has 78,000 households with a population of around 180,000 people. The borough`s working area covers more than 400km of roadway, enough to keep three Merlins busy six days a week.
"We do try to get down every road within two weeks," says fleet services manager Matt Club. However, town centre streets are all swept every day. To ensure that the oprtation meets this demand, he operates three Merlin XPs and keeps a fourth machine as a spare. "To ensure service continuity we have dedicated spares on site," he adds.
The borough has some other sweepers that are soon to be replaced by smaller Scarab Minors. Indeed it was the strength of the Minor design that first led the borough to Scarab.
"We have got some Schmidt Swingos and they are sometimes not robust enough," explains Club. "We tried the Minor first, and then went for the Merlin. The reason we need Minors is to clean precincts. Whenever we got replacements in before they tended to be Scarabs and we found that the machine is right for the job. The Merlin is more than man enough for street work."
Given their age, Sutton`s Merlin XPs are equipped with Euro 3 engines, providing even more payload for the sweeper. However London Hire has been so pleased with the Merlins performance, that it has recently ordered an additional four Scarab Merlin XP trucks on Iveco Cargo chassis, with the Euro 4 engine, to complement the fleet.